/* ══════════════════════════════════════════
     CSS VARIABLES & RESET
  ══════════════════════════════════════════ */
  :root {
    /* Notebook palette */
    --red: #DB7F67;
    --red-light: #D34F73;
    --red-dark: #A37B73;
    --bg: #fffaf4;
    --white: #fffdfa;
    --dark: #3F292B;
    --gray: #5B4542;
    --gray-light: #d9c3b6;
    --footer-bg: #3F292B;
    --card-shadow: 0 16px 38px rgba(63,41,43,0.12);
    --card-shadow-hover: 0 22px 54px rgba(211,79,115,0.2);
    --radius: 12px;
    --radius-sm: 10px;
    --radius-btn: 8px;
    --transition: all 0.25s cubic-bezier(0.34, 1.56, 0.64, 1);

    /* ── NAV dark mode overrides ── */
    --nav-bg: rgba(255,250,243,0.92);
    --nav-border: 1px solid rgba(63,41,43,0.12);
    --nav-shadow: 0 12px 34px rgba(63,41,43,0.1);
    --nav-link-color: #6f5550;
    --nav-link-color-active: #D34F73;
    --nav-link-bg-active: rgba(211,79,115,0.09);
    --nav-dropdown-bg: #fffdfa;
    --nav-dropdown-shadow: 0 18px 46px rgba(63,41,43,0.16);
    --nav-bolt-badge-bg: rgba(219,190,161,0.56);
    --nav-bolt-badge-color: #3F292B;
    --nav-bolt-badge-radius: 20px;

    /* ── NAV sizing & spacing ── */
    --nav-padding: 0 32px;
    --nav-height: 64px;
    --nav-blur: blur(16px);

    /* ── NAV logo ── */
    --nav-logo-size: 36px;
    --nav-logo-radius: 10px;
    --nav-logo-font-size: 18px;

    /* ── NAV links ── */
    --nav-link-font-weight: 700;
    --nav-link-font-size: 14px;
    --nav-link-padding: 8px 14px;
    --nav-link-radius: 8px;

    /* ── NAV dropdown ── */
    --nav-dropdown-radius: 14px;
    --nav-dropdown-min-width: 220px;

    /* ── NAV CTA button ── */
    --nav-cta-bg: #D34F73;
    --nav-cta-color: #fffdfa;
    --nav-cta-radius: 10px;
    --nav-cta-padding: 10px 24px;
    --nav-cta-font-size: 14px;
  }
  
  * { margin: 0; padding: 0; box-sizing: border-box; }
  body {
    font-family: 'Nunito Sans', system-ui, -apple-system, 'Segoe UI', 'Segoe UI Emoji', 'Apple Color Emoji', 'Noto Color Emoji', sans-serif;
    background:
      radial-gradient(circle at 12% 8%, rgba(211,79,115,0.16), transparent 24%),
      radial-gradient(circle at 86% 12%, rgba(219,127,103,0.18), transparent 28%),
      repeating-linear-gradient(180deg, transparent 0 34px, rgba(163,123,115,0.08) 34px 35px),
      linear-gradient(180deg, #fffdf9 0%, #f6e7d8 58%, #ead6c4 100%);
    color: var(--dark);
    overflow-x: hidden;
  }

  /* ── NAV ── */
  nav {
    background: var(--nav-bg); position: sticky; top: 0; z-index: 100;
    padding: var(--nav-padding); height: var(--nav-height);
    display: flex; align-items: center; justify-content: space-between;
    border-bottom: var(--nav-border);
    box-shadow: var(--nav-shadow);
    backdrop-filter: var(--nav-blur);
    -webkit-backdrop-filter: var(--nav-blur);
  }
  .nav-logo { display: flex; align-items: center; gap: 10px; cursor: pointer; text-decoration: none; flex-shrink: 0; }
  .logo-icon {
    width: var(--nav-logo-size); height: var(--nav-logo-size);
    background: var(--red); border-radius: var(--nav-logo-radius);
    display: flex; align-items: center; justify-content: center;
    font-size: 18px; font-weight: 900; color: white; font-family: 'Manrope', sans-serif;
  }
  .nav-logo span { font-family: 'Manrope', sans-serif; font-weight: 800; font-size: var(--nav-logo-font-size); color: var(--dark); }

  /* ── CENTER NAV ── */
  .nav-center { display: flex; align-items: center; gap: 4px; position: absolute; left: 50%; transform: translateX(-50%); }
  .nav-links { display: flex; align-items: center; gap: 4px; list-style: none; }
  .nav-links > li { position: relative; }
  .nav-links a, .nav-dropdown-btn {
    font-family: 'Manrope', sans-serif;
    font-weight: var(--nav-link-font-weight);
    font-size: var(--nav-link-font-size);
    color: var(--nav-link-color);
    text-decoration: none; transition: all 0.2s; cursor: pointer;
    padding: var(--nav-link-padding);
    border-radius: var(--nav-link-radius);
    background: none; border: none;
    display: flex; align-items: center; gap: 5px; white-space: nowrap;
  }
  .nav-links a:hover, .nav-links a.active,
  .nav-dropdown-btn:hover, .nav-dropdown-btn.active {
    color: var(--nav-link-color-active);
    background: var(--nav-link-bg-active);
  }
  .nav-dropdown-btn .ndrop-arrow { font-size: 10px; transition: transform 0.2s; opacity: 0.5; }
  .nav-dropdown-btn.open .ndrop-arrow { transform: rotate(180deg); opacity: 1; }

  /* ── DROPDOWN PANELS ── */
  .nav-dropdown-panel {
    display: none; position: absolute; top: calc(100% + 10px); left: 50%; transform: translateX(-50%);
    background: var(--nav-dropdown-bg);
    border-radius: var(--nav-dropdown-radius);
    box-shadow: var(--nav-dropdown-shadow);
    border: 1px solid var(--gray-light);
    min-width: var(--nav-dropdown-min-width);
    padding: 8px; z-index: 999;
    animation: dropIn 0.18s ease;
  }
  .nav-dropdown-panel.open { display: block; }
  @keyframes dropIn { from { opacity:0; transform: translateX(-50%) translateY(-6px); } to { opacity:1; transform: translateX(-50%) translateY(0); } }
  .ndp-label { font-size: 10px; font-weight: 800; color: var(--gray); text-transform: uppercase; letter-spacing: 0.08em; padding: 6px 12px 4px; display: block; }
  .ndp-item {
    display: flex; align-items: center; gap: 10px; padding: 9px 12px; border-radius: 10px;
    font-family: 'Manrope', sans-serif; font-weight: 700; font-size: 14px; color: var(--dark);
    text-decoration: none; transition: all 0.15s; cursor: pointer;
  }
  .ndp-item:hover { background: rgba(240,78,48,0.07); color: var(--red); }
  .ndp-item .ndp-icon { font-size: 18px; width: 28px; text-align: center; }
  .ndp-item .ndp-text { display: flex; flex-direction: column; }
  .ndp-item .ndp-title { font-size: 13px; font-weight: 800; line-height: 1.2; }
  .ndp-item .ndp-sub { font-size: 11px; font-weight: 600; color: var(--gray); }
  .ndp-divider { height: 1px; background: var(--gray-light); margin: 6px 8px; }

  /* ── RIGHT SIDE ── */
  .nav-right { display: flex; align-items: center; gap: 10px; flex-shrink: 0; }
  .nav-cta {
    background: var(--nav-cta-bg); color: var(--nav-cta-color);
    border: none; border-radius: var(--nav-cta-radius);
    padding: var(--nav-cta-padding);
    font-family: 'Manrope', sans-serif; font-weight: 800;
    font-size: var(--nav-cta-font-size);
    cursor: pointer; transition: var(--transition);
    box-shadow: 0 2px 12px rgba(45,27,105,0.25); white-space: nowrap;
  }
  .nav-cta:hover { opacity: 0.9; transform: scale(1.04); box-shadow: 0 4px 20px rgba(45,27,105,0.4); }
  .nav-avatar { width: 34px; height: 34px; border-radius: 8px; object-fit: cover; border: 2px solid var(--red); cursor: pointer; display:none; }
  .nav-signout { background: none; border: 1px solid var(--gray-light); color: var(--gray); border-radius: var(--radius-btn); padding: 8px 16px; font-family: 'Manrope', sans-serif; font-weight: 700; font-size: 13px; cursor: pointer; transition: var(--transition); white-space: nowrap; }
  .nav-signout:hover { border-color: var(--red); color: var(--red); }
  .nav-user-name { font-size: 13px; font-weight: 700; color: var(--dark); max-width: 90px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
  .bolt-badge {
    background: var(--nav-bolt-badge-bg);
    color: var(--nav-bolt-badge-color);
    border: 1px solid rgba(217,119,6,0.2);
    border-radius: var(--nav-bolt-badge-radius);
    padding: 6px 14px; font-family: 'Manrope', sans-serif;
    font-weight: 800; font-size: 13px; cursor: pointer;
    transition: var(--transition); display: flex; align-items: center; gap: 5px;
  }
  .bolt-badge:hover { transform: scale(1.04); box-shadow: 0 2px 12px rgba(217,119,6,0.25); }

  /* ── PAGES ── */
  .page { display: none; animation: fadeIn 0.3s ease; }
  .page.active { display: block; }
  @keyframes fadeIn { from { opacity: 0; transform: translateY(8px); } to { opacity: 1; transform: translateY(0); } }

  /* ── HERO ── */
  .hero { background: var(--bg); padding: 80px 48px 60px; text-align: center; position: relative; overflow: hidden; }
  .hero::before, .hero::after { content: ''; position: absolute; border-radius: 50%; background: rgba(240,78,48,0.12); pointer-events: none; }
  .hero::before { width: 160px; height: 160px; top: 40px; left: 60px; }
  .hero::after { width: 60px; height: 60px; bottom: 60px; right: 100px; }
  .hero-badge { display: inline-flex; align-items: center; gap: 8px; background: var(--white); border-radius: 50px; padding: 8px 18px; font-size: 13px; font-weight: 600; color: var(--dark); box-shadow: var(--card-shadow); margin-bottom: 28px; }
  .badge-dot { width: 8px; height: 8px; background: var(--red); border-radius: 50%; }
  .hero h1 { font-family: 'Manrope', sans-serif; font-size: 68px; font-weight: 900; line-height: 1.05; margin-bottom: 20px; letter-spacing: -1px; }
  .hero h1 span { color: var(--red); display: block; }
  .hero-sub { font-size: 17px; color: var(--gray); max-width: 480px; margin: 0 auto 36px; line-height: 1.6; }
  .hero-btns { display: flex; gap: 14px; justify-content: center; margin-bottom: 52px; }
  .btn-primary { background: var(--red-light); color: var(--white); border: 1px solid rgba(126,43,46,0.18); border-radius: var(--radius-btn); padding: 15px 32px; font-family: 'Manrope', sans-serif; font-weight: 800; font-size: 16px; cursor: pointer; transition: var(--transition); box-shadow: 0 6px 16px rgba(63,41,43,0.12), inset 0 1px 0 rgba(255,255,255,0.18); }
  .btn-primary:hover:not(:disabled) { background: #C23A5C; transform: translateY(-1px); box-shadow: 0 10px 22px rgba(63,41,43,0.14), inset 0 1px 0 rgba(255,255,255,0.2); }
  .btn-primary:disabled { opacity: 0.6; cursor: not-allowed; }
  .btn-secondary { background: var(--white); color: var(--dark); border: 2px solid var(--gray-light); border-radius: var(--radius-btn); padding: 15px 32px; font-family: 'Manrope', sans-serif; font-weight: 700; font-size: 16px; cursor: pointer; transition: var(--transition); }
  .btn-secondary:hover:not(:disabled) { border-color: var(--red); color: var(--red); transform: scale(1.03); }
  .hero-stats { display: flex; gap: 64px; justify-content: center; }
  .stat { text-align: center; }
  .stat-num { font-family: 'Manrope', sans-serif; font-size: 28px; font-weight: 900; color: var(--dark); }
  .stat-label { font-size: 13px; color: var(--gray); font-weight: 600; margin-top: 2px; }

  /* ── SECTIONS ── */
  section { padding: 80px 48px; }
  .section-tag { display: inline-block; background: rgba(240,78,48,0.1); color: var(--red); border-radius: 50px; padding: 6px 18px; font-size: 13px; font-weight: 700; margin-bottom: 18px; }
  .section-title { font-family: 'Manrope', sans-serif; font-size: 42px; font-weight: 900; line-height: 1.1; margin-bottom: 12px; }
  .section-sub { font-size: 16px; color: var(--gray); max-width: 520px; margin: 0 auto 52px; line-height: 1.6; }

  /* ── MODE CARDS ── */
  .modes-section { background: var(--bg); padding: 80px 48px; text-align: center; }
  .mode-grid { display: grid; grid-template-columns: repeat(3,1fr); gap: 20px; max-width: 960px; margin: 0 auto; }
  .mode-card { background: var(--red); border-radius: 20px; padding: 40px 20px 32px; cursor: pointer; transition: var(--transition); position: relative; overflow: hidden; }
  .mode-card::before { content: ''; position: absolute; inset: 0; background: linear-gradient(135deg, rgba(255,255,255,0.15) 0%, transparent 60%); }
  .mode-card:hover { transform: translateY(-6px) scale(1.02); box-shadow: 0 16px 48px rgba(240,78,48,0.4); }
  .mode-icon-wrap { width: 72px; height: 72px; background: var(--white); border-radius: 16px; display: flex; align-items: center; justify-content: center; margin: 0 auto 20px; font-size: 30px; }
  .mode-card h3 { font-family: 'Manrope', sans-serif; font-size: 22px; font-weight: 900; color: var(--dark); margin-bottom: 8px; }
  .mode-card p { font-size: 14px; color: rgba(255,255,255,0.85); font-weight: 600; }

  /* ── HOW IT WORKS ── */
  .how-section { background: var(--white); text-align: center; }
  .steps-grid { display: grid; grid-template-columns: repeat(3,1fr); gap: 40px; max-width: 900px; margin: 0 auto; }
  .step { text-align: center; }
  .step-num { width: 36px; height: 36px; background: var(--red); color: white; border-radius: 50%; display: flex; align-items: center; justify-content: center; font-family: 'Manrope', sans-serif; font-weight: 900; font-size: 15px; margin: 0 auto 12px; }
  .step-icon { font-size: 36px; margin-bottom: 16px; }
  .step h4 { font-family: 'Manrope', sans-serif; font-weight: 800; font-size: 17px; margin-bottom: 8px; }
  .step p { font-size: 14px; color: var(--gray); line-height: 1.6; }

  /* ── FOOTER ── */
  footer {
    background:
      linear-gradient(180deg, rgba(255,255,255,0.32), rgba(255,255,255,0)),
      repeating-linear-gradient(180deg, transparent 0 30px, rgba(163,123,115,0.06) 30px 31px),
      rgba(244,231,217,0.98);
    border-top: 1px solid rgba(143,69,77,0.18);
    box-shadow: inset 0 1px 0 rgba(255,255,255,0.65);
    padding: 48px 48px 28px;
    color: var(--dark);
  }
  .footer-inner { display: grid; grid-template-columns: 1fr 1fr 1fr; gap: 40px; margin-bottom: 36px; max-width: 900px; }
  .footer-brand p { font-size: 13px; color: #6B4E4C; line-height: 1.6; margin-top: 10px; }
  .footer-col h5 { font-family: 'Manrope', sans-serif; font-weight: 800; font-size: 14px; margin-bottom: 14px; color: #8F454D; }
  .footer-col a { display: block; font-size: 14px; color: #6B4E4C; text-decoration: none; margin-bottom: 8px; transition: color 0.2s; cursor: pointer; }
  .footer-col a:hover { color: var(--red); }
  .footer-bottom { border-top: 1px solid rgba(143,69,77,0.12); padding-top: 20px; font-size: 13px; color: #6B4E4C; }

  /* ── AUTH PAGE ── */
  .auth-page { min-height: calc(100vh - 64px); display: flex; flex-direction: column; }
  .auth-main { flex: 1; display: flex; align-items: center; justify-content: center; padding: 60px 20px; background: var(--bg); }
  .auth-card { background: var(--white); border-radius: 24px; padding: 52px 44px; max-width: 420px; width: 100%; box-shadow: 0 8px 40px rgba(0,0,0,0.1); text-align: center; }
  .auth-logo { width: 64px; height: 64px; background: var(--red); border-radius: 16px; display: flex; align-items: center; justify-content: center; font-size: 28px; margin: 0 auto 24px; }
  .auth-card h1 { font-family: 'Manrope', sans-serif; font-size: 28px; font-weight: 900; margin-bottom: 8px; }
  .auth-card p { font-size: 15px; color: var(--gray); margin-bottom: 36px; line-height: 1.5; }
  .google-btn { display: flex; align-items: center; justify-content: center; gap: 12px; width: 100%; padding: 14px 24px; border: 2px solid var(--gray-light); border-radius: 12px; background: var(--white); cursor: pointer; font-family: 'Manrope', sans-serif; font-weight: 700; font-size: 15px; color: var(--dark); transition: var(--transition); }
  .google-btn:hover:not(:disabled) { border-color: var(--red); background: rgba(240,78,48,0.04); transform: translateY(-2px); box-shadow: 0 4px 16px rgba(0,0,0,0.08); }
  .google-btn:disabled { opacity: 0.6; cursor: not-allowed; }
  .google-icon { width: 20px; height: 20px; }
  .auth-divider { display: flex; align-items: center; gap: 12px; margin: 24px 0; color: var(--gray); font-size: 13px; }
  .auth-divider::before, .auth-divider::after { content: ''; flex: 1; height: 1px; background: var(--gray-light); }
  .auth-features { text-align: left; margin-top: 32px; padding-top: 28px; border-top: 1px solid var(--gray-light); }
  .auth-feature { display: flex; align-items: center; gap: 10px; margin-bottom: 10px; font-size: 13px; color: var(--gray); }
  .auth-feature-icon { width: 28px; height: 28px; background: rgba(240,78,48,0.1); border-radius: 8px; display: flex; align-items: center; justify-content: center; font-size: 14px; flex-shrink: 0; }
  .auth-back { background: none; border: none; color: var(--gray); font-size: 13px; cursor: pointer; margin-top: 20px; text-decoration: underline; font-family: 'Manrope', sans-serif; }
  .auth-error { background: rgba(239,68,68,0.1); color: #dc2626; border-radius: 10px; padding: 10px 14px; font-size: 13px; font-weight: 600; margin-top: 14px; display: none; }

  /* ── UPLOAD PAGE ── */
  .upload-page-wrap { background: var(--bg); min-height: calc(100vh - 64px); display: flex; flex-direction: column; }
  .upload-hero { padding: 48px 48px 32px; text-align: center; background: var(--white); border-bottom: 1px solid var(--gray-light); }
  .upload-hero h1 { font-family: 'Manrope', sans-serif; font-size: 36px; font-weight: 900; margin-bottom: 8px; }
  .upload-hero p { font-size: 15px; color: var(--gray); }
  .upload-main { flex: 1; padding: 40px 48px; max-width: 860px; margin: 0 auto; width: 100%; }
  .drop-zone { background: var(--white); border: 2px dashed var(--gray-light); border-radius: var(--radius); padding: 60px 40px; text-align: center; cursor: pointer; transition: all 0.2s; position: relative; }
  .drop-zone:hover, .drop-zone.drag-over { border-color: var(--red); background: rgba(240,78,48,0.03); }
  .dz-icon { font-size: 52px; margin-bottom: 16px; }
  .drop-zone h3 { font-family: 'Manrope', sans-serif; font-size: 20px; font-weight: 800; margin-bottom: 8px; }
  .drop-zone p { font-size: 14px; color: var(--gray); }
  .drop-zone span { color: var(--red); font-weight: 700; }
  .dz-types { margin-top: 12px; display: flex; gap: 8px; justify-content: center; flex-wrap: wrap; }
  .dz-type-tag { background: var(--gray-light); color: var(--gray); border-radius: 50px; padding: 4px 12px; font-size: 12px; font-weight: 700; }
  .selected-file { background: var(--white); border-radius: var(--radius); padding: 20px 24px; display: flex; align-items: center; gap: 16px; box-shadow: var(--card-shadow); margin-top: 20px; }
  .file-icon { width: 48px; height: 48px; background: rgba(240,78,48,0.1); border-radius: 12px; display: flex; align-items: center; justify-content: center; font-size: 22px; flex-shrink: 0; }
  .file-info { flex: 1; }
  .file-name { font-family: 'Manrope', sans-serif; font-weight: 800; font-size: 15px; }
  .file-size { font-size: 13px; color: var(--gray); margin-top: 2px; }
  .file-remove { background: none; border: none; color: var(--gray); cursor: pointer; font-size: 18px; padding: 4px; border-radius: 6px; }
  .file-remove:hover { color: var(--red); background: rgba(240,78,48,0.08); }
  .generate-btn { background: var(--red-light); color: var(--white); border: 1px solid rgba(126,43,46,0.18); border-radius: var(--radius-btn); padding: 16px 40px; font-family: 'Manrope', sans-serif; font-weight: 800; font-size: 16px; cursor: pointer; transition: var(--transition); width: 100%; margin-top: 20px; box-shadow: 0 6px 16px rgba(63,41,43,0.12), inset 0 1px 0 rgba(255,255,255,0.18); }
  .generate-btn:hover:not(:disabled) { background: #C23A5C; transform: translateY(-1px); box-shadow: 0 10px 22px rgba(63,41,43,0.14), inset 0 1px 0 rgba(255,255,255,0.2); }
  .generate-btn:disabled { opacity: 0.6; cursor: not-allowed; }
  .loading-state { text-align: center; padding: 48px; }
  .spinner { width: 48px; height: 48px; border: 4px solid var(--gray-light); border-top-color: var(--red); border-radius: 50%; animation: spin 0.8s linear infinite; margin: 0 auto 20px; }
  @keyframes spin { to { transform: rotate(360deg); } }
  .loading-state h3 { font-family: 'Manrope', sans-serif; font-size: 20px; font-weight: 800; margin-bottom: 8px; }
  .loading-state p { font-size: 14px; color: var(--gray); }
  /* Results */
  .results-tabs { display: flex; gap: 4px; background: var(--gray-light); border-radius: var(--radius-btn); padding: 4px; margin-bottom: 24px; }
  .results-tab { flex: 1; text-align: center; padding: 10px; border-radius: calc(var(--radius-btn) - 2px); border: none; background: none; cursor: pointer; font-family: 'Manrope', sans-serif; font-weight: 700; font-size: 14px; color: var(--gray); transition: all 0.2s; }
  .results-tab.active { background: var(--white); color: var(--red); box-shadow: 0 2px 8px rgba(0,0,0,0.08); }
  .tab-content { display: none; }
  .tab-content.active { display: block; }
  .summary-card { background: var(--white); border-radius: var(--radius); padding: 28px; box-shadow: var(--card-shadow); line-height: 1.7; font-size: 15px; color: var(--dark); }
  .summary-card h3 { font-family: 'Manrope', sans-serif; font-weight: 800; font-size: 18px; margin-bottom: 14px; color: var(--dark); }
  .flashcard-mini { background: var(--white); border: 1px solid rgba(240,78,48,0.18); border-radius: var(--radius-sm); padding: 18px; box-shadow: var(--card-shadow); margin-bottom: 12px; }
  .flashcard-mini .q { font-weight: 700; font-size: 14px; margin-bottom: 6px; }
  .flashcard-mini .a { font-size: 13px; color: var(--gray); }
  .quiz-q-preview { background: var(--white); border-radius: var(--radius-sm); padding: 20px; box-shadow: var(--card-shadow); margin-bottom: 12px; }
  .quiz-q-preview .question { font-weight: 700; font-size: 14px; margin-bottom: 10px; }
  .preview-answer-hidden { display: none; }
  .preview-toggle-btn { background: none; border: 1px solid var(--gray-light); border-radius: var(--radius-btn); padding: 4px 12px; font-size: 12px; font-weight: 700; color: var(--gray); cursor: pointer; transition: var(--transition); margin-top: 6px; }
  .preview-toggle-btn:hover { border-color: var(--red); color: var(--red); }
  .quit-session-btn { background: none; border: none; color: var(--gray); font-size: 13px; font-weight: 700; cursor: pointer; padding: 6px 12px; border-radius: var(--radius-btn); transition: var(--transition); text-decoration: underline; }
  .quit-session-btn:hover { color: var(--red); }
  .quiz-option { display: flex; align-items: center; gap: 8px; padding: 6px 0; font-size: 13px; color: var(--gray); }
  .quiz-option.correct { color: #22c55e; font-weight: 700; }
  .results-actions { display: flex; gap: 12px; margin-top: 24px; flex-wrap: wrap; }
  .results-actions .btn-primary, .results-actions .btn-secondary { flex: 1; padding: 14px; font-size: 15px; }

  /* ── CHAT PAGE ── */
  .chat-page-wrap { display: flex; flex-direction: column; height: calc(100vh - 64px); }
  .chat-page-header { background: var(--white); padding: 0 48px; height: 60px; display: flex; align-items: center; justify-content: space-between; border-bottom: 1px solid var(--gray-light); flex-shrink: 0; }
  .chat-page-header h2 { font-family: 'Manrope', sans-serif; font-weight: 800; font-size: 18px; display: flex; align-items: center; gap: 10px; }
  .chat-status { font-size: 12px; color: var(--gray); font-weight: 600; }
  .chat-context-badge { background: rgba(240,78,48,0.1); color: var(--red); border-radius: 50px; padding: 4px 14px; font-size: 12px; font-weight: 700; display: none; }
  .chat-messages { flex: 1; overflow-y: auto; padding: 28px 48px; display: flex; flex-direction: column; gap: 16px; }
  .chat-msg { display: flex; gap: 12px; max-width: 760px; }
  .chat-msg.user { margin-left: auto; flex-direction: row-reverse; }
  .chat-bubble { padding: 14px 18px; border-radius: 18px; font-size: 14px; line-height: 1.6; max-width: 560px; white-space: pre-wrap; }
  .chat-bubble.bot { background: var(--white); color: var(--dark); box-shadow: var(--card-shadow); border-bottom-left-radius: 4px; }
  .chat-bubble.user { background: var(--red); color: white; border-bottom-right-radius: 4px; }
  .chat-bot-icon { width: 36px; height: 36px; background: var(--red); border-radius: 50%; display: flex; align-items: center; justify-content: center; font-size: 16px; flex-shrink: 0; }
  .chat-input-area { background: var(--white); border-top: 1px solid var(--gray-light); padding: 16px 48px; display: flex; gap: 12px; align-items: center; flex-shrink: 0; }
  .chat-input-field { flex: 1; border: 2px solid var(--gray-light); border-radius: var(--radius-btn); padding: 12px 20px; font-family: 'Manrope', sans-serif; font-size: 14px; outline: none; transition: border-color 0.2s; }
  .chat-input-field:focus { border-color: var(--red); }
  .chat-input-field:disabled { opacity: 0.6; }
  .chat-send-btn { width: 44px; height: 44px; background: var(--red-light); border: 1px solid rgba(126,43,46,0.18); border-radius: 12px; cursor: pointer; color: var(--white); font-size: 18px; display: flex; align-items: center; justify-content: center; transition: var(--transition); flex-shrink: 0; box-shadow: 0 6px 16px rgba(63,41,43,0.12), inset 0 1px 0 rgba(255,255,255,0.18); }
  .chat-send-btn:hover:not(:disabled) { background: #C23A5C; transform: translateY(-1px); }
  .chat-send-btn:disabled { opacity: 0.6; cursor: not-allowed; }
  .chat-typing { display: flex; gap: 4px; align-items: center; padding: 4px 0; }
  .chat-typing span { width: 6px; height: 6px; background: var(--gray); border-radius: 50%; animation: bounce 1.2s infinite; }
  .chat-typing span:nth-child(2) { animation-delay: 0.15s; }
  .chat-typing span:nth-child(3) { animation-delay: 0.3s; }
  @keyframes bounce { 0%,60%,100%{transform:translateY(0)} 30%{transform:translateY(-6px)} }
  /* "Use for review" button in chat */
  .chat-review-btn { background: rgba(240,78,48,0.1); color: var(--red); border: none; border-radius: var(--radius-btn); padding: 8px 18px; font-family: 'Manrope', sans-serif; font-weight: 700; font-size: 13px; cursor: pointer; transition: var(--transition); }
  .chat-review-btn:hover { background: rgba(240,78,48,0.2); }

  /* ── REVIEW PAGE ── */
  .review-page-wrap { background: var(--bg); min-height: calc(100vh - 64px); display: flex; flex-direction: column; }
  .review-page-header { background: var(--white); padding: 0 48px; height: 60px; display: flex; align-items: center; gap: 20px; border-bottom: 1px solid var(--gray-light); }
  .review-page-header h2 { font-family: 'Manrope', sans-serif; font-weight: 800; font-size: 18px; }
  .review-mode-tabs { display: flex; gap: 4px; background: var(--gray-light); border-radius: var(--radius-btn); padding: 3px; }
  .review-mode-tab { padding: 7px 20px; border-radius: calc(var(--radius-btn) - 2px); border: none; background: none; cursor: pointer; font-family: 'Manrope', sans-serif; font-weight: 700; font-size: 13px; color: var(--gray); transition: all 0.2s; }
  .review-mode-tab.active { background: var(--white); color: var(--red); box-shadow: 0 2px 6px rgba(0,0,0,0.06); }
  .review-main { flex: 1; display: flex; flex-direction: column; align-items: center; justify-content: center; padding: 40px 48px; }
  /* Flashcard */
  .fc-progress-bar { width: 100%; max-width: 560px; height: 6px; background: var(--gray-light); border-radius: 3px; margin-bottom: 12px; overflow: hidden; }
  .fc-progress-fill { height: 100%; background: var(--red); border-radius: 3px; transition: width 0.4s ease; }
  .fc-label { font-size: 13px; color: var(--gray); font-weight: 700; margin-bottom: 28px; text-align: center; }
  .flashcard-wrap { width: 100%; max-width: 560px; height: 300px; perspective: 1000px; cursor: pointer; margin-bottom: 24px; }
  .flashcard-inner { width: 100%; height: 100%; position: relative; transform-style: preserve-3d; transition: transform 0.5s cubic-bezier(0.4,0,0.2,1); }
  .flashcard-wrap.flipped .flashcard-inner { transform: rotateY(180deg); }
  .flashcard-face { position: absolute; inset: 0; background: var(--white); border-radius: var(--radius); box-shadow: var(--card-shadow); display: flex; flex-direction: column; align-items: center; justify-content: center; padding: 36px; backface-visibility: hidden; -webkit-backface-visibility: hidden; }
  .flashcard-back { transform: rotateY(180deg); background: var(--red); }
  .fc-side-label { font-size: 11px; font-weight: 800; letter-spacing: 1px; text-transform: uppercase; color: var(--gray); margin-bottom: 16px; }
  .flashcard-back .fc-side-label { color: rgba(255,255,255,0.7); }
  .fc-text { font-family: 'Manrope', sans-serif; font-size: 20px; font-weight: 800; text-align: center; line-height: 1.4; color: var(--dark); }
  .flashcard-back .fc-text { color: var(--dark); }
  .fc-hint { font-size: 13px; color: var(--gray); text-align: center; margin-bottom: 20px; }
  .fc-btns { display: flex; gap: 12px; }
  .btn-gray { background: var(--white); color: var(--gray); border: 2px solid var(--gray-light); border-radius: var(--radius-btn); padding: 12px 28px; font-family: 'Manrope', sans-serif; font-weight: 700; font-size: 14px; cursor: pointer; transition: var(--transition); }
  .btn-gray:hover { border-color: var(--gray); transform: scale(1.03); }
  .btn-red { background: var(--red-light); color: var(--white); border: 1px solid rgba(126,43,46,0.18); border-radius: var(--radius-btn); padding: 12px 28px; font-family: 'Manrope', sans-serif; font-weight: 800; font-size: 14px; cursor: pointer; transition: var(--transition); box-shadow: 0 6px 14px rgba(63,41,43,0.12), inset 0 1px 0 rgba(255,255,255,0.18); }
  .btn-red:hover:not(:disabled) { background: #C23A5C; transform: translateY(-1px); box-shadow: 0 10px 20px rgba(63,41,43,0.14), inset 0 1px 0 rgba(255,255,255,0.2); }
  /* Quiz */
  .quiz-wrap { width: 100%; max-width: 620px; }
  .quiz-card { background: var(--white); border-radius: var(--radius); box-shadow: var(--card-shadow); padding: 32px; }
  .quiz-num { font-size: 13px; color: var(--gray); font-weight: 700; margin-bottom: 16px; }
  .quiz-question { font-family: 'Manrope', sans-serif; font-size: 20px; font-weight: 800; margin-bottom: 24px; line-height: 1.4; }
  .quiz-options { display: flex; flex-direction: column; gap: 10px; }
  .quiz-opt { display: flex; align-items: center; gap: 14px; padding: 14px 18px; border: 2px solid var(--gray-light); border-radius: var(--radius-sm); cursor: pointer; transition: all 0.2s; font-weight: 600; font-size: 14px; background: var(--white); text-align: left; }
  .quiz-opt:hover:not(.disabled) { border-color: var(--red); background: rgba(240,78,48,0.04); }
  .quiz-opt.correct { border-color: #22c55e; background: rgba(34,197,94,0.08); color: #15803d; }
  .quiz-opt.wrong { border-color: var(--gray-light); background: rgba(239,68,68,0.08); color: #991b1b; }
  .quiz-opt.disabled { cursor: default; }
  .quiz-opt-letter { width: 28px; height: 28px; border-radius: 50%; background: var(--gray-light); display: flex; align-items: center; justify-content: center; font-size: 12px; font-weight: 800; flex-shrink: 0; }
  .quiz-next-btn { margin-top: 20px; width: 100%; }
  .quiz-score { text-align: center; padding: 40px 20px; }
  .quiz-score .trophy { font-size: 64px; margin-bottom: 16px; }
  /* No-upload state */
  .no-upload { text-align: center; padding: 40px 20px; }
  .no-upload .icon { font-size: 52px; margin-bottom: 16px; }
  .no-upload h3 { font-family: 'Manrope', sans-serif; font-size: 22px; font-weight: 800; margin-bottom: 8px; }
  .no-upload p { font-size: 14px; color: var(--gray); margin-bottom: 20px; }
  /* Review topic generator */
  .review-topic-section { background: var(--white); border-radius: var(--radius); padding: 28px; box-shadow: var(--card-shadow); margin-bottom: 24px; width: 100%; max-width: 620px; }
  .review-topic-section h4 { font-family: 'Manrope', sans-serif; font-weight: 800; font-size: 16px; margin-bottom: 12px; }
  .topic-input-row { display: flex; gap: 10px; }
  .topic-input { flex: 1; border: 2px solid var(--gray-light); border-radius: var(--radius-btn); padding: 10px 18px; font-family: 'Manrope', sans-serif; font-size: 14px; outline: none; transition: border-color 0.2s; }
  .topic-input:focus { border-color: var(--red); }
  .topic-input:disabled { opacity: 0.6; }
  .gen-mode-tabs { display: flex; gap: 8px; margin: 14px 0 0; }
  .gen-mode-btn { flex: 1; padding: 9px; border-radius: var(--radius-btn); border: 2px solid var(--gray-light); background: var(--white); cursor: pointer; font-family: 'Manrope', sans-serif; font-weight: 700; font-size: 13px; color: var(--gray); transition: all 0.2s; }
  .gen-mode-btn.active { border-color: var(--red); color: var(--red); background: rgba(240,78,48,0.06); }
  .gen-spinner { display: none; margin: 20px auto; }
  .gen-spinner.visible { display: block; }

  /* ── TOAST ── */
  .toast { position: fixed; bottom: 72px; left: 50%; transform: translateX(-50%) translateY(120%); background: var(--dark); color: var(--white); padding: 12px 24px; border-radius: 12px; font-size: 14px; font-weight: 600; z-index: 9999; transition: transform 0.3s cubic-bezier(0.34,1.56,0.64,1), opacity 0.4s ease; opacity: 0; pointer-events: none; white-space: nowrap; }
  .toast.show { transform: translateX(-50%) translateY(0); opacity: 1; }
  .toast.hide { transform: translateX(-50%) translateY(0); opacity: 0; }
  .toast.success { background: #22c55e; }
  .toast.error { background: #ef4444; }

  /* ── MOBILE BOTTOM NAV ── */
  .mobile-nav { display: none; position: fixed !important; bottom: 0 !important; left: 0 !important; right: 0 !important; top: auto !important; background: var(--white); border-top: 1px solid var(--gray-light); z-index: 9999 !important; padding: 8px 0 env(safe-area-inset-bottom, 8px); box-shadow: 0 -4px 20px rgba(0,0,0,0.08); }
  .mobile-nav-inner { display: flex; justify-content: space-around; align-items: center; }
  .mobile-nav-btn { display: flex; flex-direction: column; align-items: center; gap: 3px; background: none; border: none; cursor: pointer; padding: 6px 12px; border-radius: 12px; transition: all 0.2s; min-width: 60px; }
  .mobile-nav-btn .mnb-icon { font-size: 22px; line-height: 1; }
  .mobile-nav-btn .mnb-label { font-family: 'Manrope', sans-serif; font-size: 10px; font-weight: 700; color: var(--gray); }
  .mobile-nav-btn.active .mnb-label { color: var(--red); }
  .mobile-nav-btn.active .mnb-icon { transform: scale(1.15); }

  /* ── RESPONSE MODE TOGGLE ── */
  .mode-toggle { display: flex; align-items: center; gap: 6px; background: var(--gray-light); border-radius: var(--radius-btn); padding: 3px; }
  .mode-toggle-btn { padding: 5px 12px; border-radius: calc(var(--radius-btn) - 2px); border: none; background: none; cursor: pointer; font-family: 'Manrope', sans-serif; font-weight: 700; font-size: 12px; color: var(--gray); transition: all 0.2s; white-space: nowrap; }
  .mode-toggle-btn.active { background: var(--white); color: var(--red); box-shadow: 0 1px 4px rgba(0,0,0,0.1); }

  /* ── MORE TOOLS TOGGLE ── */
  .more-tools-toggle { background: var(--white); border: 2px solid var(--gray-light); border-radius: var(--radius-btn); padding: 12px 32px; font-family: 'Manrope', sans-serif; font-weight: 700; font-size: 15px; color: var(--dark); cursor: pointer; transition: var(--transition); display: inline-flex; align-items: center; gap: 8px; }
  .more-tools-toggle:hover { border-color: var(--red); background: rgba(240,78,48,0.04); transform: translateY(-2px); }
  .more-tools-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 10px; max-width: 100%; opacity: 0; max-height: 0; overflow: hidden; transition: all 0.4s ease; }
  .more-tools-grid.expanded { opacity: 1; max-height: 600px; display: grid; }

  /* -- SECONDARY TOOL CARDS -- */
  .tool-card { background: var(--white); border: 2px solid var(--gray-light); border-radius: 16px; padding: 22px 18px 20px; cursor: pointer; transition: var(--transition); display: flex; flex-direction: column; align-items: flex-start; text-align: left; position: relative; overflow: hidden; }
  .tool-card:hover { border-color: var(--red); box-shadow: 0 8px 24px rgba(240,78,48,0.10); transform: translateY(-3px); }
  .tool-card .mode-icon-wrap { background: var(--gray-light); border-radius: 12px; width: 44px; height: 44px; margin: 0 0 12px; font-size: 20px; }
  .tool-card h3 { font-size: 15px; font-weight: 900; color: var(--dark); margin-bottom: 4px; }
  .tool-card p { font-size: 12px; color: #9ca3af; font-weight: 600; line-height: 1.5; }
  /* -- PREMIUM NOTES CARD -- */
  .tool-card-premium { background: var(--white); border: 2px solid var(--gray-light); border-radius: 14px; padding: 22px 18px 20px; cursor: pointer; transition: var(--transition); display: flex; flex-direction: column; align-items: flex-start; text-align: left; position: relative; overflow: hidden; }
  .tool-card-premium::before { content: ''; position: absolute; inset: 0; background: linear-gradient(135deg, rgba(211,79,115,0.10) 0%, transparent 60%); }
  .tool-card-premium:hover { transform: translateY(-2px); box-shadow: 0 16px 38px rgba(63,41,43,0.14); border-color: rgba(211,79,115,0.25); }
  .tool-card-premium .mode-icon-wrap { background: rgba(211,79,115,0.10); border-radius: 12px; width: 44px; height: 44px; margin: 0 0 12px; font-size: 20px; }
  .tool-card-premium h3 { font-size: 15px; font-weight: 900; color: var(--dark); margin-bottom: 4px; }
  .tool-card-premium p { font-size: 12px; color: var(--gray); font-weight: 600; line-height: 1.5; }
  .tool-card-premium .premium-tag { position: absolute; top: 12px; right: 12px; background: rgba(255,215,0,0.18); color: #ffd700; font-size: 9px; font-weight: 900; letter-spacing: 1px; padding: 3px 8px; border-radius: 20px; text-transform: uppercase; }

  /* ── CALCULATOR ── */
  .calc-num { background: var(--white); border: 2px solid var(--gray-light); border-radius: 12px; padding: 20px; font-size: 18px; font-weight: 700; cursor: pointer; transition: all 0.2s; }
  .calc-num:hover { border-color: var(--red); background: rgba(240,78,48,0.04); }
  .calc-num:active { transform: scale(0.95); }
  .calc-input { width: 100%; border: 2px solid var(--gray-light); border-radius: 12px; padding: 14px 16px; font-family: 'Manrope', sans-serif; font-size: 16px; margin-bottom: 12px; outline: none; transition: border-color 0.2s; }
  .calc-input:focus { border-color: var(--red); }
  .calc-history-item { background: var(--bg); border-radius: 12px; padding: 10px 12px; margin-bottom: 8px; border: 1px solid rgba(0,0,0,0.04); }
  .calc-history-top { display:flex; align-items:flex-start; justify-content:space-between; gap:10px; }
  .calc-history-expr { font-size: 13px; font-weight: 700; color: var(--dark); }
  .calc-history-answer { font-size: 13px; color: var(--gray); margin-top: 2px; word-break: break-word; }
  .copy-btn { background: var(--white); border: 2px solid var(--gray-light); color: var(--gray); border-radius: var(--radius-btn); padding: 8px 14px; font-weight: 700; cursor: pointer; font-size: 13px; transition: var(--transition); white-space: nowrap; }
  .copy-btn:hover:not(:disabled) { border-color: var(--red); color: var(--red); transform: translateY(-1px); }
  .copy-btn:disabled { opacity: 0.6; cursor: not-allowed; }
  .topic-count { width: 88px; border: 2px solid var(--gray-light); border-radius: var(--radius-btn); padding: 10px 14px; font-family: 'Manrope', sans-serif; font-size: 14px; outline: none; transition: border-color 0.2s; }
  .topic-count:focus { border-color: var(--red); }
  .preview-head { display:flex; align-items:center; justify-content:space-between; gap:12px; margin-bottom: 10px; }
  .preview-copy-wrap { display:flex; justify-content:flex-end; margin-top: 8px; }
  .review-nav-row { display:flex; gap:12px; margin-top: 18px; flex-wrap: wrap; }
  .review-nav-btn { flex:1; min-width: 140px; }

  /* ── FORMATTED CHAT RESPONSE ── */
  .chat-bubble.bot { line-height: 1.65; }
  .chat-bubble.bot strong { font-weight: 800; color: var(--dark); }
  .chat-bubble.bot .resp-simple p { margin-bottom: 8px; }
  .chat-bubble.bot .resp-advanced p { margin-bottom: 8px; }
  .chat-bubble.bot .resp-advanced ul { padding-left: 18px; margin-bottom: 8px; }
  .chat-bubble.bot .resp-advanced li { margin-bottom: 4px; }
  .chat-bubble.bot .resp-advanced h4 { font-family: 'Manrope', sans-serif; font-weight: 800; font-size: 14px; margin: 10px 0 4px; color: var(--dark); }
  .groq-credit { font-size: 10px; color: rgba(255,255,255,0.5); text-align: center; padding: 2px 0 6px; }
  .groq-credit a { color: rgba(255,255,255,0.6); text-decoration: none; }
  .groq-credit a:hover { color: white; }

  /* ── CHAT HISTORY SIDEBAR ── */
  .chat-layout { display: flex; height: calc(100vh - 64px); }
  .chat-history-sidebar { width: 240px; background: var(--white); border-right: 1px solid var(--gray-light); display: flex; flex-direction: column; flex-shrink: 0; overflow: hidden; }
  .chat-history-sidebar.hidden { display: none; }
  .sidebar-header { padding: 14px 16px; border-bottom: 1px solid var(--gray-light); display: flex; align-items: center; justify-content: space-between; }
  .sidebar-header h4 { font-family: 'Manrope', sans-serif; font-weight: 800; font-size: 14px; }
  .new-chat-btn { background: linear-gradient(135deg, #1a1a2e 0%, #2d1b69 100%); color: #ffd700; border: none; border-radius: 8px; padding: 6px 12px; font-family: 'Manrope', sans-serif; font-weight: 700; font-size: 12px; cursor: pointer; transition: var(--transition); }
  .new-chat-btn:hover { background: linear-gradient(135deg, #2d1b69 0%, #1a1a2e 100%); }
  .chat-history-list { flex: 1; overflow-y: auto; padding: 8px; }
  .history-item { padding: 10px 12px; border-radius: 10px; cursor: pointer; transition: background 0.15s; border: none; background: none; width: 100%; text-align: left; }
  .history-item:hover { background: var(--bg); }
  .history-item.active { background: rgba(240,78,48,0.08); }
  .history-item-title { font-family: 'Manrope', sans-serif; font-weight: 700; font-size: 13px; color: var(--dark); white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
  .history-item-date { font-size: 11px; color: var(--gray); margin-top: 2px; }
  .history-item-del { float: right; background: none; border: none; color: var(--gray); cursor: pointer; font-size: 14px; padding: 0 2px; opacity: 0; transition: opacity 0.15s; }
  .history-item:hover .history-item-del { opacity: 1; }
  .sidebar-toggle { background: none; border: none; color: var(--gray); cursor: pointer; font-size: 18px; padding: 4px 8px; border-radius: 6px; transition: color 0.2s; }
  .sidebar-toggle:hover { color: var(--red); }
  .chat-main-area { flex: 1; display: flex; flex-direction: column; overflow: hidden; min-width: 0; }

  /* ── MOBILE DROPDOWN NAV ── */
  .mobile-menu-btn { display: none; background: none; border: none; cursor: pointer; padding: 6px; border-radius: 10px; transition: background 0.2s; }
  .mobile-menu-btn:hover { background: var(--gray-light); }
  .mobile-menu-btn span { display: block; width: 22px; height: 2px; background: var(--dark); border-radius: 2px; transition: all 0.25s; margin: 4px 0; }
  .mobile-menu-btn.open span:nth-child(1) { transform: translateY(6px) rotate(45deg); }
  .mobile-menu-btn.open span:nth-child(2) { opacity: 0; }
  .mobile-menu-btn.open span:nth-child(3) { transform: translateY(-6px) rotate(-45deg); }

  /* ── MOBILE DROPDOWN (hamburger panel) ── */
  .mobile-dropdown { display: none; position: absolute; top: 100%; left: 0; right: 0; background: var(--white); border-bottom: 1px solid var(--gray-light); box-shadow: 0 12px 32px rgba(0,0,0,0.12); z-index: 999; padding: 12px 12px 16px; }
  .mobile-dropdown.open { display: block; }
  .mdd-section { margin-bottom: 6px; }
  .mdd-section-title { font-size: 10px; font-weight: 800; color: var(--gray); text-transform: uppercase; letter-spacing: 0.08em; padding: 8px 10px 4px; display: block; }
  .mdd-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 6px; padding: 0 2px; }
  .mdd-card {
    display: flex; align-items: center; gap: 10px; padding: 10px 12px; border-radius: 12px;
    background: var(--white); text-decoration: none; cursor: pointer; transition: all 0.15s;
    border: 1px solid transparent;
  }
  .mdd-card:hover, .mdd-card.mdd-active { background: rgba(240,78,48,0.07); border-color: rgba(240,78,48,0.15); }
  .mdd-card .mdd-icon { font-size: 20px; flex-shrink: 0; }
  .mdd-card .mdd-info { display: flex; flex-direction: column; }
  .mdd-card .mdd-name { font-family: 'Manrope', sans-serif; font-weight: 800; font-size: 13px; color: var(--dark); line-height: 1.2; }
  .mdd-card:hover .mdd-name, .mdd-card.mdd-active .mdd-name { color: var(--red); }
  .mdd-card .mdd-desc { font-family: 'Manrope', sans-serif; font-weight: 600; font-size: 10px; color: var(--gray); line-height: 1.2; }
  .mdd-card-full { grid-column: 1 / -1; }
  .mdd-divider { height: 1px; background: var(--gray-light); margin: 8px 4px; }
  .mdd-cta-row { padding: 4px 2px 0; }
  .mdd-cta { display: block; background: linear-gradient(135deg, #1a1a2e 0%, #2d1b69 100%); color: #ffd700 !important; border-radius: 12px; text-align: center; padding: 13px 20px; font-family: 'Manrope', sans-serif; font-weight: 800; font-size: 14px; text-decoration: none; }
  .mdd-signout { display: block; width: 100%; background: none; border: 1px solid var(--gray-light); color: var(--gray); border-radius: 12px; text-align: center; padding: 11px 20px; font-family: 'Manrope', sans-serif; font-weight: 700; font-size: 14px; cursor: pointer; margin-top: 6px; }
  .mdd-signout:hover { border-color: var(--red); color: var(--red); }

  @media (max-width: 768px) {
    nav { padding: 0 16px; height: 54px; position: relative; z-index: 200; }
    .nav-center { display: none; }
    .nav-right { display: none; }
    .mobile-menu-btn { display: block; }
    .mobile-nav { display: block; }
    .more-tools-desktop-toggle { display: none !important; }
    .hero { padding: 28px 16px 24px; }
    .hero h1 { font-size: 30px; line-height: 1.2; }
    .hero-sub { font-size: 15px; }
    .hero-stats { gap: 16px; flex-wrap: wrap; justify-content: center; }
    .hero-stats .stat-num { font-size: 22px; }
    .hero-stats .stat-label { font-size: 11px; }
    .btn-primary, .btn-secondary { padding: 11px 22px; font-size: 14px; }
    .hero-btns { gap: 10px; flex-wrap: wrap; justify-content: center; }
    .hero-btns .btn-primary, .hero-btns .btn-secondary { flex: 1; min-width: 130px; text-align: center; }
    .modes-section, section { padding: 28px 16px; }
    .section-title { font-size: 22px; }
    .mode-grid { grid-template-columns: 1fr 1fr; gap: 10px; }
    .mode-card { padding: 16px 12px; }
    .mode-card h4 { font-size: 13px; }
    .mode-icon-wrap { font-size: 24px; margin-bottom: 8px; }
    .steps-grid { grid-template-columns: 1fr; gap: 16px; }
    .footer-inner { grid-template-columns: 1fr; gap: 20px; }
    .upload-main { padding: 16px 12px; }
    .upload-hero { padding: 20px 16px 12px; }
    .upload-hero h1 { font-size: 20px; }
    .drop-zone { padding: 36px 20px; }
    .dz-icon { font-size: 36px; }
    .chat-page-wrap, .chat-layout { height: calc(100vh - 54px - 58px); }
    .chat-messages { padding: 12px; }
    .chat-input-area { padding: 10px 12px; }
    .chat-page-header { padding: 0 12px; min-height: 50px; }
    .chat-history-sidebar { display: none; }
    .review-page-header { padding: 0 12px; flex-wrap: wrap; height: auto; padding-top: 10px; padding-bottom: 10px; gap: 6px; }
    .review-main { padding: 16px 12px; }
    .review-nav-row { gap: 8px; }
    .review-nav-btn { padding: 10px 8px; font-size: 13px; }
    .auth-card { padding: 28px 18px; margin: 0 12px; }
    .auth-submit-btn { padding: 11px; font-size: 14px; }
    body { padding-bottom: 58px; }
    .toast { bottom: 72px; }
  }

  @media (max-width: 400px) {
    .mode-grid { grid-template-columns: 1fr; }
    .hero h1 { font-size: 26px; }
  }
/* ── AUTH TABS ── */
  .auth-tabs { display:flex; background:var(--gray-light); border-radius:12px; padding:3px; margin-bottom:24px; }
  .auth-tab { flex:1; padding:9px; border:none; background:none; border-radius:10px; font-family:'Manrope',sans-serif; font-weight:700; font-size:13px; color:var(--gray); cursor:pointer; transition:all 0.2s; }
  .auth-tab.active { background: var(--white); color:var(--red); box-shadow:0 1px 4px rgba(0,0,0,0.1); }
  .auth-panel { display:none; }
  .auth-panel.active { display:block; }
  .auth-input-group { display:flex; flex-direction:column; gap:10px; margin-bottom:16px; }
  .auth-input { width:100%; padding:12px 14px; border:2px solid var(--gray-light); border-radius:10px; font-family:'Manrope',sans-serif; font-size:14px; font-weight:600; outline:none; transition:border 0.2s; box-sizing:border-box; }
  .auth-input:focus { border-color:var(--red); }
  .auth-submit-btn { width:100%; padding:13px; background:var(--red); color:white; border:none; border-radius:12px; font-family:'Manrope',sans-serif; font-weight:800; font-size:15px; cursor:pointer; transition:var(--transition); margin-bottom:10px; }
  .auth-submit-btn:hover:not(:disabled) { background:var(--red-light); transform:translateY(-1px); }
  .auth-submit-btn:disabled { opacity:0.6; cursor:not-allowed; }
  .otp-boxes { display:flex; gap:8px; justify-content:center; margin:12px 0 16px; }
  .otp-box { width:44px; height:52px; border:2px solid var(--gray-light); border-radius:10px; text-align:center; font-family:'Manrope',sans-serif; font-size:22px; font-weight:800; outline:none; transition:border 0.2s; }
  .otp-box:focus { border-color:var(--red); }
  .auth-link-btn { background:none; border:none; color:var(--red); font-family:'Manrope',sans-serif; font-weight:700; font-size:13px; cursor:pointer; text-decoration:underline; }
  .auth-success { color:#22c55e; font-size:13px; font-weight:700; margin-bottom:8px; display:none; }
  .otp-step { display:none; }
  .otp-step.active { display:block; }

  /* Grammar highlight overlay */
  .grammar-wrapper { position: relative; margin-bottom: 16px; }
  .grammar-highlight-layer { position: absolute; inset: 0; padding: 16px; font-family: 'Manrope', sans-serif; font-size: 15px; line-height: 1.6; white-space: pre-wrap; word-wrap: break-word; overflow: hidden; pointer-events: none; border-radius: 12px; color: transparent; border: 2px solid transparent; box-sizing: border-box; }
  .grammar-highlight-layer mark.err { background: rgba(239,68,68,0.18); border-bottom: 2.5px solid #ef4444; border-radius: 2px; color: transparent; }
  #grammar-input { position: relative; background: transparent !important; caret-color: var(--dark); z-index: 1; }
  .grammar-errors-list { margin-top: 4px; }
  .grammar-errors-list h5 { font-weight: 800; font-size: 13px; color: var(--gray); margin-bottom: 8px; }
  .grammar-error-item { display: flex; gap: 10px; align-items: flex-start; background: var(--white); border: 1px solid #fecaca; border-radius: 8px; padding: 10px 12px; margin-bottom: 6px; font-size: 13px; }
  .grammar-error-item .err-badge { background: #ef4444; color: white; border-radius: 4px; padding: 1px 6px; font-size: 11px; font-weight: 800; white-space: nowrap; flex-shrink: 0; margin-top: 1px; }
  .grammar-error-item .err-strike { color: #ef4444; text-decoration: line-through; }
  .grammar-error-item .err-fix { color: #16a34a; font-weight: 700; }
  .grammar-error-item .err-reason { color: var(--gray); }
  .grammar-clean-badge { display: inline-flex; align-items: center; gap: 6px; background: #f0fdf4; border: 1px solid #86efac; border-radius: 8px; padding: 8px 14px; font-size: 13px; font-weight: 700; color: #16a34a; margin-top: 4px; }


/* ── Question box ── */
.btn-ask {
  font-size: 13px; padding: 6px 14px; border-radius: 8px;
  border: 1px solid #bfdbfe; background: #eff6ff; color: #1d4ed8;
  cursor: pointer; margin: 4px 0 10px; font-family: 'Manrope', sans-serif; font-weight: 700;
  transition: background .2s; display: inline-flex; align-items: center; gap: 6px;
}
.btn-ask:hover { background: #dbeafe; }
.qa-box { margin-bottom: 12px; }
.qa-input {
  width: 100%; padding: 9px 12px; border: 2px solid #bfdbfe;
  border-radius: 10px; font-family: 'Manrope', sans-serif; font-size: 13px;
  outline: none; resize: none; box-sizing: border-box; min-height: 54px;
  transition: border-color .2s; background: #f8faff;
}
.qa-input:focus { border-color: #3b82f6; background: var(--white); }
.btn-send-q {
  margin-top: 6px; padding: 7px 18px; border-radius: 8px;
  background: #3b82f6; color: white; border: none;
  font-family: 'Manrope', sans-serif; font-weight: 700; font-size: 13px;
  cursor: pointer; transition: background .2s;
}
.btn-send-q:hover:not(:disabled) { background: #2563eb; }
.btn-send-q:disabled { opacity: .45; cursor: not-allowed; }
.qa-answer {
  margin-top: 10px; padding: 12px 14px;
  background: #eff6ff; border: 1px solid #bfdbfe; border-radius: 10px;
  font-size: 13px; color: #1e3a8a; line-height: 1.6; display: none; white-space: pre-wrap;
}
.qa-answer.visible { display: block; }
.validate-feedback {
  margin-top: 8px; padding: 10px 14px; border-radius: 10px;
  font-size: 13px; line-height: 1.5; display: none;
}
.validate-feedback.fail { display: block; background: rgba(239,68,68,.08); border: 1px solid rgba(239,68,68,.25); color: #dc2626; }
.validate-feedback.pass { display: block; background: rgba(34,197,94,.08); border: 1px solid #86efac; color: #15803d; }

/* Zappi playful light redesign - global palette refresh */
:root,
html[data-theme="light"] {
  color-scheme: light;
  --red: #DB7F67;
  --red-light: #D34F73;
  --red-dark: #A37B73;
  --bg: #fffaf4;
  --white: #fffdfa;
  --dark: #3F292B;
  --gray: #5B4542;
  --gray-light: #d9c3b6;
  --footer-bg: #3F292B;
  --card-shadow: 0 18px 42px rgba(63, 41, 43, 0.13);
  --card-shadow-hover: 0 22px 54px rgba(211, 79, 115, 0.2);
  --nav-bg: rgba(255, 250, 243, 0.9);
  --nav-border: 1px solid rgba(63, 41, 43, 0.12);
  --nav-shadow: 0 12px 34px rgba(63, 41, 43, 0.1);
  --nav-link-color: #6f5550;
  --nav-link-color-active: #D34F73;
  --nav-link-bg-active: rgba(211, 79, 115, 0.12);
  --nav-dropdown-bg: #fffdfa;
  --nav-dropdown-shadow: 0 18px 46px rgba(63, 41, 43, 0.16);
  --nav-bolt-badge-bg: rgba(219, 190, 161, 0.52);
  --nav-bolt-badge-color: #3F292B;
  --nav-cta-bg: linear-gradient(135deg, #D34F73, #DB7F67);
  --nav-cta-color: #fffdfa;
}

html[data-theme="light"],
html[data-theme="light"] body,
body {
  background:
    radial-gradient(circle at 10% 8%, rgba(211,79,115,.14), transparent 26%),
    radial-gradient(circle at 88% 10%, rgba(219,127,103,.16), transparent 28%),
    repeating-linear-gradient(180deg, transparent 0 34px, rgba(163,123,115,.08) 34px 35px),
    linear-gradient(180deg, #fffdf9 0%, #f6e7d8 58%, #ead6c4 100%) !important;
  color: #3F292B;
}

body,
button,
input,
select,
textarea {
  font-family: 'Manrope', system-ui, sans-serif;
}

h1, h2, h3, h4, h5,
.section-title,
.hero h1,
.mode-card h3,
.nav-logo span,
.chat-page-header h2,
.review-title,
.upload-hero h1,
.auth-card h1,
.tool-card h3,
.timer-display {
  font-family: 'Sora', 'Manrope', system-ui, sans-serif !important;
  letter-spacing: 0 !important;
}

nav,
.zappi-topbar,
.hero,
.modes-section,
.how-section,
.upload-page-wrap,
.upload-hero,
.auth-main,
.chat-page-wrap,
.chat-layout,
.chat-main-area,
.review-page-wrap,
.review-main,
.arena-page,
.settings-page,
.features-page,
.about-page {
  background: transparent !important;
  color: #3F292B !important;
}

nav {
  background: rgba(255,250,243,.9) !important;
  border-bottom: 1px solid rgba(63,41,43,.12) !important;
  box-shadow: 0 12px 34px rgba(63,41,43,.1) !important;
}

.nav-logo span,
.nav-user-name,
.nav-links a,
.nav-dropdown-btn {
  color: #3F292B !important;
}

.nav-links a:hover,
.nav-links a.active,
.nav-dropdown-btn:hover,
.nav-dropdown-btn.active {
  color: #D34F73 !important;
  background: rgba(211,79,115,.12) !important;
}

.logo-icon,
.auth-logo,
.step-num {
  background: linear-gradient(135deg, #D34F73, #DB7F67) !important;
  color: #fffdfa !important;
}

.nav-dropdown-panel,
.mobile-dropdown,
.auth-card,
.drop-zone,
.selected-file,
.result-card,
.mode-card,
.tool-card,
.chat-history-sidebar,
.chat-bubble,
.review-card,
.settings-card,
.history-item,
.calc-history-item,
.grammar-error-item,

.qa-answer,
.validate-feedback,
.upload-main > div,
.feature-card {
  background: rgba(255,255,252,.97) !important;
  border-color: rgba(63,41,43,.13) !important;
  color: #3F292B !important;
  box-shadow: 0 16px 38px rgba(63,41,43,.12) !important;
}

.mode-card,
.tool-card-premium {
  background:
    linear-gradient(135deg, rgba(211,79,115,.18), rgba(219,127,103,.16)),
    #fffdfa !important;
}

.mode-card p,
.tool-card-premium p,
.section-sub,
.hero-sub,
.step p,
.upload-hero p,
.auth-card p,
.file-size,
.history-item-date,
.ndp-sub,
.mdd-card .mdd-desc {
  color: #5B4542 !important;
}

.btn-primary,
.generate-btn,
.auth-submit-btn,
.nav-cta,
.new-chat-btn,
.mdd-cta,
.btn-send-q {
  background: linear-gradient(135deg, #D34F73, #DB7F67) !important;
  color: #fffdfa !important;
  border-color: transparent !important;
  box-shadow: 0 12px 28px rgba(211,79,115,.24) !important;
}

.btn-primary:hover:not(:disabled),
.generate-btn:hover:not(:disabled),
.auth-submit-btn:hover:not(:disabled),
.nav-cta:hover {
  transform: translateY(-2px) scale(1.03);
  box-shadow: 0 18px 36px rgba(211,79,115,.28) !important;
}

.btn-secondary,
.google-btn,
.copy-btn,
.nav-signout,
.mdd-signout,
.preset-btn,
.calc-num,
.file-remove,
.auth-tab,
.btn-ask {
  background: rgba(255,255,252,.94) !important;
  color: #3F292B !important;
  border-color: rgba(163,123,115,.28) !important;
}

.btn-secondary:hover:not(:disabled),
.google-btn:hover:not(:disabled),
.copy-btn:hover:not(:disabled),
.preset-btn:hover,
.calc-num:hover,
.btn-ask:hover {
  color: #D34F73 !important;
  background: rgba(211,79,115,.1) !important;
  border-color: rgba(211,79,115,.35) !important;
}

input,
textarea,
select,
.auth-input,
.calc-input,
.topic-count,
.qa-input,
#grammar-input {
  background: rgba(255,255,252,.97) !important;
  color: #3F292B !important;
  border-color: rgba(163,123,115,.28) !important;
}

input:focus,
textarea:focus,
select:focus,
.auth-input:focus,
.calc-input:focus,
.topic-count:focus,
.qa-input:focus {
  border-color: #D34F73 !important;
  box-shadow: 0 0 0 4px rgba(211,79,115,.12) !important;
}

.section-tag,
.hero-badge,
.dz-type-tag,
.auth-feature-icon,
.bolt-badge,
.bolt-item-cost,
.premium-tag {
  background: rgba(219,190,161,.48) !important;
  color: #3F292B !important;
  border-color: rgba(163,123,115,.28) !important;
}

.badge-dot,
.spinner {
  background: #D34F73 !important;
}

.spinner {
  border-color: #DBBEA1 !important;
  border-top-color: #D34F73 !important;
}

.chat-bubble.bot,
.qa-answer,
.validate-feedback.pass {
  background: rgba(219,190,161,.3) !important;
  border-color: rgba(163,123,115,.24) !important;
  color: #3F292B !important;
}

.chat-bubble.user {
  background: linear-gradient(135deg, #D34F73, #DB7F67) !important;
  color: #fffdfa !important;
}

.nav-dropdown-panel,
.mobile-dropdown {
  border-radius: 18px !important;
}

.ndp-label,
.mdd-section-title,
.mdd2-label,
.bolt-section-label {
  color: #A37B73 !important;
}

.ndp-item,
.mdd-card,
.mdd2-row,
.znav-tool-item {
  color: #3F292B !important;
}

.ndp-item:hover,
.ndp-item.ndp-current,
.mdd-card:hover,
.mdd-card.mdd-active,
.mdd2-row:hover,
.mdd2-row.mdd-active,
.history-item:hover,
.history-item.active {
  background: rgba(211,79,115,.1) !important;
  color: #D34F73 !important;
}

footer {
  background:
    linear-gradient(180deg, rgba(255,255,255,0.32), rgba(255,255,255,0)),
    repeating-linear-gradient(180deg, transparent 0 30px, rgba(163,123,115,0.06) 30px 31px),
    rgba(244,231,217,0.98) !important;
  color: #3F292B !important;
  border-top: 1px solid rgba(143,69,77,0.18) !important;
  box-shadow: inset 0 1px 0 rgba(255,255,255,0.65) !important;
}

footer a,
.footer-brand p,
.footer-bottom {
  color: #6B4E4C !important;
}

footer a:hover {
  color: #D34F73 !important;
}

::selection {
  background: rgba(211,79,115,.22);
  color: #3F292B;
}

/* -- Zappi playful notebook refresh ------------------------------------- */
:root {
  color-scheme: light;
  --red: oklch(64% 0.13 20);
  --red-light: oklch(61% 0.17 8);
  --red-dark: oklch(42% 0.055 24);
  --bg: oklch(96.8% 0.028 73);
  --white: oklch(99% 0.012 75);
  --dark: oklch(24% 0.045 24);
  --gray: oklch(42% 0.04 35);
  --gray-light: oklch(84% 0.04 59);
  --paper: oklch(98.7% 0.017 75);
  --paper-soft: oklch(95.7% 0.035 72);
  --paper-warm: oklch(91.5% 0.047 61);
  --ink: oklch(24% 0.045 24);
  --ink-soft: oklch(42% 0.04 35);
  --line: color-mix(in oklch, var(--red-dark) 15%, transparent);
  --rose: oklch(61% 0.17 8);
  --coral: oklch(66% 0.13 32);
  --mint: oklch(79% 0.085 155);
  --sky: oklch(78% 0.075 222);
  --butter: oklch(86% 0.105 88);
  --surface: color-mix(in oklch, var(--paper) 92%, white);
  --surface-strong: color-mix(in oklch, var(--paper) 84%, var(--butter) 16%);
  --border-soft: color-mix(in oklch, var(--red-dark) 20%, transparent);
  --shadow-pencil: 0 1px 0 color-mix(in oklch, white 78%, transparent), 0 14px 32px rgba(63, 41, 43, .11);
  --shadow-lift: 0 20px 44px rgba(63, 41, 43, .14);
  --radius: 8px;
  --radius-sm: 8px;
  --radius-btn: 8px;
  --ease-out: cubic-bezier(.23, 1, .32, 1);
  --ease-in-out: cubic-bezier(.77, 0, .175, 1);
  --transition: transform 180ms var(--ease-out), opacity 180ms var(--ease-out), color 180ms ease, background-color 180ms ease, border-color 180ms ease, box-shadow 180ms var(--ease-out);
  --card-shadow: var(--shadow-pencil);
  --card-shadow-hover: var(--shadow-lift);
}

html[data-theme="light"],
html[data-theme="light"] body,
body {
  background:
    linear-gradient(90deg, transparent 0 74px, rgba(211, 79, 115, .13) 74px 76px, transparent 76px),
    repeating-linear-gradient(180deg, transparent 0 33px, var(--line) 33px 34px),
    linear-gradient(135deg, rgba(167, 220, 190, .20), transparent 34%),
    linear-gradient(180deg, var(--paper) 0%, var(--paper-soft) 58%, var(--paper-warm) 100%) !important;
  color: var(--ink) !important;
  text-rendering: optimizeLegibility;
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  background-image:
    radial-gradient(circle, rgba(63, 41, 43, .055) 1px, transparent 1.3px),
    linear-gradient(135deg, rgba(255,255,255,.24), rgba(255,255,255,0));
  background-size: 18px 18px, 100% 100%;
  mask-image: linear-gradient(180deg, rgba(0,0,0,.72), rgba(0,0,0,.18));
}

body,
button,
input,
select,
textarea {
  font-family: 'Manrope', 'Nunito Sans', system-ui, -apple-system, 'Segoe UI', sans-serif !important;
}

h1, h2, h3, h4, h5,
.section-title,
.hero h1,
.mode-card h3,
.tool-card h3,
.auth-card h1,
.upload-hero h1,
.chat-page-header h2,
.review-title,
.timer-display {
  font-family: 'Sora', 'Manrope', 'Nunito Sans', system-ui, sans-serif !important;
  letter-spacing: 0 !important;
}

section,
.hero,
.modes-section,
.how-section,
.upload-page-wrap,
.upload-hero,
.auth-main,
.chat-page-wrap,
.chat-layout,
.chat-main-area,
.review-page-wrap,
.review-main,
.arena-page,
.settings-page,
.features-page,
.about-page,
.page-wrap {
  background: transparent !important;
  color: var(--ink) !important;
}

.hero {
  max-width: 1240px;
  margin: 0 auto;
  min-height: min(760px, calc(100dvh - 64px));
  padding: clamp(72px, 9vw, 116px) clamp(20px, 5vw, 72px) clamp(50px, 7vw, 88px) !important;
  text-align: left !important;
  isolation: isolate;
}

.hero::before {
  width: clamp(220px, 28vw, 360px) !important;
  height: clamp(260px, 34vw, 430px) !important;
  inset: 92px clamp(20px, 6vw, 84px) auto auto !important;
  border-radius: 8px !important;
  background:
    linear-gradient(90deg, rgba(211,79,115,.22) 0 2px, transparent 2px),
    repeating-linear-gradient(180deg, transparent 0 25px, rgba(64,41,43,.10) 25px 26px),
    linear-gradient(145deg, rgba(255,255,252,.96), rgba(255,244,232,.92)) !important;
  border: 1px solid rgba(63,41,43,.12);
  box-shadow: -18px 20px 0 rgba(167,220,190,.34), 16px 18px 0 rgba(141,197,224,.24), var(--shadow-lift);
  transform: rotate(2.4deg);
  z-index: -1;
}

.hero::after {
  width: 128px !important;
  height: 92px !important;
  inset: auto clamp(36px, 11vw, 160px) clamp(80px, 11vw, 150px) auto !important;
  border-radius: 8px !important;
  background:
    linear-gradient(135deg, rgba(255,255,255,.38), rgba(255,255,255,0) 45%),
    var(--butter) !important;
  box-shadow: 0 16px 28px rgba(63,41,43,.13);
  transform: rotate(-6deg);
  z-index: -1;
}

.hero-badge,
.section-tag,
.dz-type-tag,
.auth-feature-icon,
.bolt-badge,
.bolt-item-cost,
.premium-tag {
  border: 1px solid var(--border-soft) !important;
  border-radius: 999px !important;
  background: color-mix(in oklch, var(--butter) 42%, var(--surface)) !important;
  color: var(--ink) !important;
  box-shadow: inset 0 1px 0 rgba(255,255,255,.55) !important;
}

.badge-dot {
  background: var(--mint) !important;
  box-shadow: 0 0 0 4px color-mix(in oklch, var(--mint) 24%, transparent);
}

.hero h1 {
  max-width: 11ch;
  font-size: clamp(42px, 7vw, 82px) !important;
  line-height: .96 !important;
}

.hero h1 span,
.page-header h1 span,
a {
  color: var(--rose) !important;
}

.hero-sub,
.section-sub,
.step p,
.upload-hero p,
.auth-card p,
.file-size,
.history-item-date,
.ndp-sub,
.mdd-card .mdd-desc,
p,
small {
  color: var(--ink-soft) !important;
}

.hero-sub {
  margin-left: 0 !important;
  max-width: 54ch !important;
}

.hero-btns,
.results-actions,
.review-nav-row {
  justify-content: flex-start !important;
}

.hero-stats {
  justify-content: flex-start !important;
  gap: clamp(22px, 5vw, 62px) !important;
}

.stat {
  position: relative;
}

.stat::after {
  content: "";
  position: absolute;
  left: 50%;
  right: auto;
  bottom: -8px;
  width: 42px;
  height: 7px;
  transform: translateX(-50%) rotate(-1deg);
  border-radius: 999px;
  background: color-mix(in oklch, var(--sky) 48%, transparent);
}

.auth-card,
.drop-zone,
.selected-file,
.result-card,
.summary-card,
.flashcard-mini,
.quiz-q-preview,
.quiz-card,
.review-topic-section,
.mode-card,
.tool-card,
.tool-card-premium,
.chat-history-sidebar,
.chat-bubble,
.review-card,
.settings-card,
.history-item,
.calc-history-item,
.grammar-error-item,

.qa-answer,
.validate-feedback,
.upload-main > div,
.feature-card,
.file-card,
.note-card,
.panel,
.card,
.stat-card,
.editor-card,
.details-card {
  background: var(--surface) !important;
  border: 1px solid var(--border-soft) !important;
  border-radius: 8px !important;
  color: var(--ink) !important;
  box-shadow: var(--shadow-pencil) !important;
}

.mode-card,
.tool-card-premium,
.feature-card:nth-child(3n + 1) {
  background:
    linear-gradient(135deg, color-mix(in oklch, var(--mint) 26%, transparent), transparent 58%),
    var(--surface) !important;
}

.feature-card:nth-child(3n + 2),
.tool-card:nth-child(3n + 2) {
  background:
    linear-gradient(135deg, color-mix(in oklch, var(--sky) 25%, transparent), transparent 58%),
    var(--surface) !important;
}

.feature-card:nth-child(3n),
.tool-card:nth-child(3n) {
  background:
    linear-gradient(135deg, color-mix(in oklch, var(--butter) 30%, transparent), transparent 58%),
    var(--surface) !important;
}

.mode-card::after,
.tool-card::after,
.feature-card::after {
  content: "";
  position: absolute;
  top: 10px;
  right: 12px;
  width: 46px;
  height: 11px;
  border-radius: 3px;
  background: color-mix(in oklch, var(--sky) 45%, transparent);
  transform: rotate(2deg);
  pointer-events: none;
}

.mode-grid {
  grid-template-columns: minmax(0, 1.12fr) minmax(260px, .88fr) !important;
  align-items: stretch;
}

.mode-card:first-child {
  grid-row: span 2;
}

.mode-card,
.tool-card,
.feature-card,
.calc-num,
.history-item,
.topic-input-row,
.review-page-header,
.review-header-actions,
.results-actions,
.upload-tray-head,
.usl-head,
.ndp-item,
.mdd2-row,
.znav-tool-item {
  transition: var(--transition) !important;
}

.page-header,
.features-hero,
.about-hero,
.settings-hero,
.review-page-header,
.review-history-frame,
.upload-hero,
.upload-main,
.tool-page,
.notes-page,
.messages-coming-soon,
.zcs-shell,
.bolts-page {
  max-width: min(1180px, calc(100vw - 32px)) !important;
  margin-left: auto !important;
  margin-right: auto !important;
}

.review-page-header,
.review-history-head,
.review-header-actions,
.topic-input-row,
.results-actions,
.upload-tray-head,
.usl-head,
.calc-actions,
.tool-actions,
.settings-actions {
  min-width: 0;
}

.topic-input-row {
  align-items: stretch;
  flex-wrap: wrap;
}

.topic-input {
  min-width: min(260px, 100%);
}

.topic-count {
  flex: 0 0 88px;
}

.topic-input-row .btn-red,
.topic-input-row .primary-btn,
.topic-input-row .submit-btn {
  flex: 0 0 auto;
  min-width: 124px;
}

.review-header-actions,
.results-actions,
.upload-tray-head,
.usl-head,
.calc-actions,
.tool-actions {
  flex-wrap: wrap;
}

.review-history-empty,
.usl-empty,
.empty-state,
.no-upload,
.validate-feedback,
.auth-error {
  line-height: 1.45 !important;
}

.btn-primary:focus-visible,
.btn-secondary:focus-visible,
.generate-btn:focus-visible,
.auth-submit-btn:focus-visible,
.nav-cta:focus-visible,
.nav-signout:focus-visible,
.copy-btn:focus-visible,
.calc-num:focus-visible,
.toolbar-btn:focus-visible,
.review-start-btn:focus-visible,
.review-history-refresh:focus-visible,
.topic-input-row .btn-red:focus-visible,
button:focus-visible,
a:focus-visible {
  outline: 0 !important;
  box-shadow: 0 0 0 4px color-mix(in oklch, var(--rose) 18%, transparent), var(--shadow-pencil) !important;
}

button:disabled,
.btn-primary:disabled,
.btn-secondary:disabled,
.generate-btn:disabled,
.auth-submit-btn:disabled,
.btn-red:disabled,
.primary-btn:disabled,
.submit-btn:disabled {
  transform: none !important;
  filter: saturate(.72);
}

@media (hover: hover) and (pointer: fine) {
  .mode-card:hover,
  .tool-card:hover,
  .feature-card:hover,
  .calc-num:hover,
  .history-item:hover {
    transform: translateY(-3px) rotate(-.25deg) !important;
    box-shadow: var(--shadow-lift) !important;
    border-color: color-mix(in oklch, var(--rose) 42%, transparent) !important;
  }

  .btn-primary:hover:not(:disabled),
  .generate-btn:hover:not(:disabled),
  .auth-submit-btn:hover:not(:disabled),
  .nav-cta:hover,
  .new-chat-btn:hover,
  .btn-red:hover:not(:disabled),
  .btn-send-q:hover:not(:disabled) {
    transform: translateY(-2px) !important;
    box-shadow: 0 18px 34px rgba(177, 63, 85, .22) !important;
  }
}

.btn-primary,
.generate-btn,
.auth-submit-btn,
.nav-cta,
.new-chat-btn,
.mdd-cta,
.btn-red,
.btn-send-q,

.primary-btn,
.submit-btn {
  background: linear-gradient(135deg, var(--rose), var(--coral)) !important;
  color: var(--white) !important;
  border: 1px solid color-mix(in oklch, var(--rose) 40%, transparent) !important;
  border-radius: 8px !important;
  box-shadow: 0 12px 24px rgba(177, 63, 85, .19), inset 0 1px 0 rgba(255,255,255,.24) !important;
  transition: var(--transition) !important;
}

.btn-secondary,
.google-btn,
.copy-btn,
.nav-signout,
.mdd-signout,
.preset-btn,
.calc-num,
.file-remove,
.auth-tab,
.btn-ask,
.secondary-btn,
.toolbar-btn {
  background: color-mix(in oklch, var(--surface) 88%, white) !important;
  color: var(--ink) !important;
  border: 1px solid var(--border-soft) !important;
  border-radius: 8px !important;
  transition: var(--transition) !important;
}

.btn-primary:active,
.btn-secondary:active,
.generate-btn:active,
.auth-submit-btn:active,
.nav-cta:active,
.nav-signout:active,
.copy-btn:active,
.calc-num:active,
.toolbar-btn:active,
button:active {
  transform: scale(.97) !important;
}

input,
textarea,
select,
.auth-input,
.calc-input,
.topic-count,
.qa-input,
#grammar-input,
#wc-input {
  background: color-mix(in oklch, var(--surface) 94%, white) !important;
  color: var(--ink) !important;
  border: 1px solid var(--border-soft) !important;
  border-radius: 8px !important;
  box-shadow: inset 0 1px 0 rgba(255,255,255,.5) !important;
  transition: border-color 160ms ease, box-shadow 160ms ease, background-color 160ms ease !important;
}

input:focus,
textarea:focus,
select:focus,
.auth-input:focus,
.calc-input:focus,
.topic-count:focus,
.qa-input:focus,
#grammar-input:focus,
#wc-input:focus {
  border-color: var(--rose) !important;
  box-shadow: 0 0 0 4px color-mix(in oklch, var(--rose) 18%, transparent), inset 0 1px 0 rgba(255,255,255,.5) !important;
  outline: none !important;
}

select:not([hidden]):not([multiple]) {
  appearance: none !important;
  -webkit-appearance: none !important;
  padding-right: 44px !important;
  cursor: pointer;
  background-image:
    linear-gradient(45deg, transparent 50%, #8f5f5b 50%),
    linear-gradient(135deg, #8f5f5b 50%, transparent 50%),
    linear-gradient(180deg, rgba(219,190,161,.36), rgba(255,255,252,.18)) !important;
  background-position:
    calc(100% - 22px) calc(50% - 3px),
    calc(100% - 16px) calc(50% - 3px),
    100% 0 !important;
  background-size: 7px 7px, 7px 7px, 42px 100% !important;
  background-repeat: no-repeat !important;
}

select:not([hidden]):not([multiple]):hover {
  border-color: rgba(211,79,115,.36) !important;
  background-image:
    linear-gradient(45deg, transparent 50%, #D34F73 50%),
    linear-gradient(135deg, #D34F73 50%, transparent 50%),
    linear-gradient(180deg, rgba(211,79,115,.13), rgba(255,255,252,.22)) !important;
}

select::-ms-expand {
  display: none;
}

.chat-bubble.bot,
.qa-answer,
.validate-feedback.pass {
  background:
    repeating-linear-gradient(180deg, transparent 0 29px, rgba(63,41,43,.07) 29px 30px),
    color-mix(in oklch, var(--mint) 18%, var(--surface)) !important;
  border-color: color-mix(in oklch, var(--mint) 32%, var(--border-soft)) !important;
}

.chat-bubble.user {
  background: linear-gradient(135deg, var(--rose), var(--coral)) !important;
  color: var(--white) !important;
}

.results-tabs,
.mode-toggle,
.auth-tabs {
  background: color-mix(in oklch, var(--paper-warm) 48%, white) !important;
  border: 1px solid var(--border-soft);
  border-radius: 10px !important;
  padding: 4px !important;
}

.results-tab.active,
.mode-toggle-btn.active,
.auth-tab.active {
  background: var(--surface) !important;
  color: var(--rose) !important;
  box-shadow: 0 8px 18px rgba(63,41,43,.08) !important;
}

.spinner {
  width: 42px !important;
  height: 42px !important;
  border: 3px solid color-mix(in oklch, var(--butter) 65%, white) !important;
  border-top-color: var(--rose) !important;
  background: transparent !important;
  animation-duration: .7s !important;
}

.toast {
  border-radius: 8px !important;
  background: var(--ink) !important;
  color: var(--paper) !important;
  box-shadow: var(--shadow-lift) !important;
  transition: transform 220ms var(--ease-out), opacity 180ms ease !important;
}

#znav {
  max-width: none !important;
}

#znav-tools-menu {
  position: absolute !important;
  left: 50% !important;
  bottom: calc(100% + 10px) !important;
  top: auto !important;
  flex-direction: column !important;
  gap: 2px !important;
  width: max-content !important;
  min-width: 210px !important;
  max-width: calc(100vw - 32px) !important;
  padding: 8px !important;
  transform-origin: bottom center !important;
  transform: translateX(-50%) scaleY(.92) !important;
}

#znav-tools-menu:not(.open) {
  visibility: hidden !important;
  max-height: 0 !important;
  opacity: 0 !important;
  pointer-events: none !important;
  padding-top: 0 !important;
  padding-bottom: 0 !important;
  border-color: transparent !important;
  box-shadow: none !important;
}

#znav-tools-menu.open {
  visibility: visible !important;
  max-height: min(420px, calc(100vh - 190px)) !important;
  opacity: 1 !important;
  pointer-events: auto !important;
  overflow: auto !important;
  transform: translateX(-50%) scaleY(1) !important;
}

.chat-quickbar {
  scrollbar-width: none;
}

.chat-quickbar::-webkit-scrollbar {
  display: none;
}

.zpack-icon {
  display: inline-block;
  width: 1.18em;
  height: 1.18em;
  object-fit: contain;
  vertical-align: -0.22em;
  flex: 0 0 auto;
  filter: drop-shadow(0 1px 0 rgba(255,255,255,.28));
}

.zpack-label {
  display: inline-flex;
  align-items: center;
  justify-content: inherit;
  gap: .42em;
  min-width: 0;
}

button .zpack-label,
a .zpack-label {
  pointer-events: none;
}

.zpack-icon-sm {
  width: 18px;
  height: 18px;
}

.zpack-icon-md {
  width: 28px;
  height: 28px;
}

.zpack-icon-lg {
  width: 44px;
  height: 44px;
}

footer {
  background:
    linear-gradient(90deg, transparent 0 74px, rgba(255, 213, 188, .08) 74px 76px, transparent 76px),
    repeating-linear-gradient(180deg, transparent 0 30px, rgba(255,239,226,.07) 30px 31px),
    oklch(29% .045 24) !important;
  color: oklch(96% .02 70) !important;
  border-top: 1px solid rgba(255,231,214,.14) !important;
}

footer a,
.footer-brand p,
.footer-bottom,
.footer-brand-tagline,
.footer-col h5 {
  color: oklch(94% .022 70) !important;
}

@media (max-width: 860px) {
  .hero {
    min-height: auto;
    padding: 58px 20px 44px !important;
  }

  .hero::before,
  .hero::after {
    opacity: .35;
    transform: rotate(1deg) scale(.82);
  }

  .mode-grid {
    grid-template-columns: 1fr !important;
  }

  .mode-card:first-child {
    grid-row: auto;
  }

  .chat-quickbar {
    flex-wrap: wrap !important;
    overflow: visible !important;
    gap: 8px !important;
  }

  .chat-chip {
    flex: 1 1 calc(50% - 8px) !important;
    min-width: 124px !important;
  }
}

@media (max-width: 640px) {
  body {
    padding-bottom: calc(76px + env(safe-area-inset-bottom, 0px));
  }

  section,
  .review-main,
  .upload-main {
    padding-left: 14px !important;
    padding-right: 14px !important;
  }

  .hero {
    max-width: calc(100vw - 28px) !important;
    padding: 42px 18px 34px !important;
    overflow: hidden;
  }

  .hero::before,
  .hero::after {
    display: none !important;
  }

  .hero h1 {
    max-width: 10ch;
    font-size: clamp(42px, 13vw, 54px) !important;
    line-height: 1.02 !important;
  }

  .hero-sub {
    font-size: 16px !important;
    line-height: 1.55 !important;
  }

  .hero-btns,
  .results-actions,
  .review-nav-row {
    flex-direction: column;
    width: 100%;
  }

  .hero-btns > *,
  .results-actions > *,
  .review-nav-row > * {
    width: 100%;
    justify-content: center;
  }

  .hero-stats {
    display: grid !important;
    grid-template-columns: 1fr !important;
    gap: 12px !important;
  }

  .stat {
    text-align: left !important;
  }

  .stat::after {
    left: 14px;
    transform: rotate(-1deg);
  }

  .review-page-header {
    align-items: stretch !important;
  }

  .review-page-header h2 {
    width: 100%;
  }

  .review-mode-tabs,
  .review-header-actions {
    width: 100%;
  }

  .review-header-actions > *,
  .review-mode-tab {
    flex: 1 1 0;
  }

  .review-topic-section {
    padding: 22px 16px !important;
  }

  .topic-input-row {
    display: grid !important;
    grid-template-columns: minmax(0, 1fr) 72px;
    gap: 10px !important;
  }

  .topic-input {
    min-width: 0;
  }

  .topic-input-row .btn-red,
  .topic-input-row .primary-btn,
  .topic-input-row .submit-btn {
    grid-column: 1 / -1;
    width: 100%;
    min-width: 0;
  }

  .zdsp-button {
    bottom: calc(84px + env(safe-area-inset-bottom, 0px)) !important;
  }

  .zdsp-window {
    bottom: calc(88px + env(safe-area-inset-bottom, 0px)) !important;
    top: auto !important;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    scroll-behavior: auto !important;
    transition-duration: .001ms !important;
  }
}