:root {
    --bg: #ffffff;
    --bg-secondary: #f5f5f5;
    --bg-tertiary: #eeeeee;
    --text: #1a1a1a;
    --text-secondary: #666666;
    --text-muted: #999999;
    --border: #e5e5e5;
    --btn-bg: #1a1a1a;
    --btn-text: #ffffff;
    --link: #0066cc;
    --danger: #dc2626;
    --danger-bg: #fef2f2;
    --success: #2e7d32;
    --success-bg: #e8f5e9;
    --radius: 8px;
  }

  @media (prefers-color-scheme: dark) {
    :root {
      --bg: #1a1a1a;
      --bg-secondary: #262626;
      --bg-tertiary: #333333;
      --text: #e5e5e5;
      --text-secondary: #999999;
      --text-muted: #777777;
      --border: #333333;
      --btn-bg: #e5e5e5;
      --btn-text: #1a1a1a;
      --link: #4d9fff;
      --danger: #ef4444;
      --danger-bg: rgba(239, 68, 68, 0.1);
      --success: #4ade80;
      --success-bg: rgba(34, 197, 94, 0.1);
    }
  }

  [data-theme="dark"] {
    --bg: #1a1a1a;
    --bg-secondary: #262626;
    --bg-tertiary: #333333;
    --text: #e5e5e5;
    --text-secondary: #999999;
    --text-muted: #777777;
    --border: #333333;
    --btn-bg: #e5e5e5;
    --btn-text: #1a1a1a;
    --link: #4d9fff;
    --danger: #ef4444;
    --danger-bg: rgba(239, 68, 68, 0.1);
    --success: #4ade80;
    --success-bg: rgba(34, 197, 94, 0.1);
  }

  * { margin: 0; padding: 0; box-sizing: border-box; }

  body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.7;
    font-size: 16px;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
  }

  .container { max-width: 1080px; margin: 0 auto; padding: 0 24px; }

  a { color: var(--link); text-decoration: none; }
  a:hover { text-decoration: underline; }

  .btn {
    display: inline-block;
    padding: 12px 28px;
    border-radius: var(--radius);
    font-weight: 600;
    font-size: 0.95rem;
    cursor: pointer;
    border: none;
    transition: opacity 0.15s;
    text-decoration: none;
    font-family: inherit;
  }
  .btn-primary { background: var(--btn-bg); color: var(--btn-text); }
  .btn-primary:hover { opacity: 0.85; text-decoration: none; }
  .btn-outline { background: transparent; color: var(--text); border: 1.5px solid var(--border); }
  .btn-outline:hover { border-color: var(--text); text-decoration: none; }
  .btn-large { padding: 16px 36px; font-size: 1rem; }

  .section-label {
    display: inline-block;
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: var(--text-muted);
    margin-bottom: 12px;
  }

  h1 { font-size: clamp(2.2rem, 5vw, 3.2rem); line-height: 1.15; font-weight: 700; letter-spacing: -0.02em; }
  h2 { font-size: clamp(1.6rem, 3.5vw, 2.2rem); line-height: 1.2; font-weight: 700; letter-spacing: -0.01em; }
  h3 { font-size: 1.15rem; font-weight: 600; }

  .text-danger { color: var(--danger); }
  .text-success { color: var(--success); }
  .text-secondary { color: var(--text-secondary); }

  /* ── Marker Highlight ── */
  mark.marker {
    background-color: transparent;
    color: inherit;
  }
  .marker {
    background-image: linear-gradient(to right, rgba(255, 224, 102, 0.45), rgba(255, 224, 102, 0.45));
    background-size: 100% 40%;
    background-repeat: no-repeat;
    background-position: 0 90%;
    padding: 0 2px;
    box-decoration-break: clone;
    -webkit-box-decoration-break: clone;
  }
  @media (prefers-color-scheme: dark) {
    .marker {
      background-image: linear-gradient(to right, rgba(255, 224, 102, 0.2), rgba(255, 224, 102, 0.2));
    }
  }
  [data-theme="dark"] .marker {
    background-image: linear-gradient(to right, rgba(255, 224, 102, 0.2), rgba(255, 224, 102, 0.2));
  }

  /* ── Nav ── */
  nav {
    padding: 14px 0;
    border-bottom: 1px solid var(--border);
    position: sticky;
    top: 0;
    background: var(--bg);
    z-index: 100;
  }
  nav .container { display: flex; align-items: center; justify-content: space-between; }
  .nav-logo { font-size: 1.2rem; font-weight: 700; color: var(--text); }
  .nav-links { display: flex; gap: 28px; align-items: center; }
  .nav-links a { color: var(--text-secondary); font-size: 0.9rem; font-weight: 500; }
  .nav-links a:hover { color: var(--text); text-decoration: none; }

  /* ── Hero ── */
  .hero { padding: 96px 0 72px; }
  .hero-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 64px; align-items: center; }
  .hero p { font-size: 1.1rem; color: var(--text-secondary); margin: 20px 0 32px; line-height: 1.7; }
  .hero-actions { display: flex; gap: 12px; flex-wrap: wrap; }
  .hero-free { margin-top: 14px; font-size: 0.85rem; color: var(--text-muted); }

  .hero-visual {
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 36px;
  }

  .score-compare {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 24px;
  }
  .score-box {
    text-align: center;
    padding: 24px;
    border-radius: var(--radius);
    min-width: 140px;
  }
  .score-box.before { background: var(--danger-bg); border: 1.5px solid var(--danger); }
  .score-box.after { background: var(--success-bg); border: 1.5px solid var(--success); }
  .score-box .score-num { font-size: 2.8rem; font-weight: 700; line-height: 1; }
  .score-box.before .score-num { color: var(--danger); }
  .score-box.after .score-num { color: var(--success); }
  .score-box .score-label { font-size: 0.8rem; font-weight: 500; color: var(--text-secondary); margin-top: 8px; }
  .score-arrow { font-size: 1.5rem; color: var(--text-muted); }
  .score-improvement { text-align: center; margin-top: 16px; font-size: 0.9rem; font-weight: 600; color: var(--text); }

  /* ── Warning Banner ── */
  .warning-banner {
    background: var(--btn-bg);
    color: var(--btn-text);
    padding: 48px 0;
    text-align: center;
  }
  .warning-banner h2 { color: var(--danger); font-size: clamp(1.4rem, 3.5vw, 2rem); margin-bottom: 12px; font-weight: 700; }
  .warning-banner p { color: var(--text-muted); font-size: 1.05rem; max-width: 680px; margin: 0 auto; }
  @media (prefers-color-scheme: dark) {
    .warning-banner { background: #111; }
    .warning-banner p { color: #aaa; }
  }
  [data-theme="dark"] .warning-banner { background: #111; }
  [data-theme="dark"] .warning-banner p { color: #aaa; }

  /* ── Funnel ── */
  .funnel { padding: 96px 0; background: var(--bg-secondary); }
  .funnel-steps {
    display: grid;
    grid-template-columns: 1fr auto 1fr auto 1fr;
    gap: 0;
    align-items: start;
    margin-top: 48px;
    max-width: 880px;
    margin-left: auto;
    margin-right: auto;
  }
  .funnel-step {
    text-align: center;
    padding: 28px 20px;
    border-radius: var(--radius);
    background: var(--bg);
    border: 1px solid var(--border);
  }
  .funnel-step .step-icon { font-size: 2rem; margin-bottom: 12px; }
  .funnel-step h3 { margin-bottom: 8px; }
  .funnel-step p { font-size: 0.85rem; color: var(--text-secondary); }
  .funnel-step .reject-rate {
    display: inline-block;
    margin-top: 12px;
    padding: 4px 12px;
    background: var(--danger-bg);
    color: var(--danger);
    border-radius: var(--radius);
    font-size: 0.8rem;
    font-weight: 600;
  }
  .funnel-step .pass-rate {
    display: inline-block;
    margin-top: 12px;
    padding: 4px 12px;
    background: var(--success-bg);
    color: var(--success);
    border-radius: var(--radius);
    font-size: 0.8rem;
    font-weight: 600;
  }
  .funnel-arrow {
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.2rem;
    color: var(--text-muted);
    padding-top: 48px;
  }
  .funnel-note {
    text-align: center;
    margin-top: 32px;
    font-size: 1rem;
    color: var(--text-secondary);
  }
  .funnel-note strong { color: var(--danger); }

  /* ── Stats ── */
  .stats { padding: 64px 0; border-bottom: 1px solid var(--border); }
  .stats-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
  .stat-card { text-align: center; padding: 28px 16px; }
  .stat-card .stat-num { font-size: 2.2rem; font-weight: 700; color: var(--text); line-height: 1; }
  .stat-card .stat-label { font-size: 0.85rem; color: var(--text-secondary); margin-top: 8px; }
  .stat-card .stat-source { font-size: 0.7rem; color: var(--text-muted); margin-top: 4px; }

  /* ── Before/After ── */
  .before-after { padding: 96px 0; }
  .ba-table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 32px;
    font-size: 0.95rem;
  }
  .ba-table th { padding: 12px 16px; text-align: left; font-weight: 600; border-bottom: 2px solid var(--border); color: var(--text-muted); font-size: 0.8rem; text-transform: uppercase; letter-spacing: 0.04em; }
  .ba-table td { padding: 12px 16px; border-bottom: 1px solid var(--border); }
  .ba-table .score-before { color: var(--danger); font-weight: 600; }
  .ba-table .score-after { color: var(--success); font-weight: 600; }
  .ba-table .improvement { color: var(--text); font-weight: 600; }
  .ba-table tr:last-child { background: var(--bg-secondary); font-weight: 600; }

  /* ── Why Not ChatGPT ── */
  .why-not { padding: 96px 0; background: var(--bg-secondary); }
  .why-not-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; margin-top: 40px; }
  .why-not-card { padding: 28px; background: var(--bg); border-radius: var(--radius); border: 1px solid var(--border); }
  .why-not-card .card-icon { font-size: 1.8rem; margin-bottom: 14px; }
  .why-not-card h3 { margin-bottom: 10px; }
  .why-not-card p { color: var(--text-secondary); font-size: 0.9rem; }

  /* ── Not Cheating ── */
  .not-cheating { padding: 96px 0; }
  .not-cheating-inner {
    max-width: 680px;
    margin: 0 auto;
    text-align: center;
  }
  .not-cheating-box {
    margin: 32px 0;
    padding: 32px;
    background: var(--bg-secondary);
    border-radius: var(--radius);
    border: 1px solid var(--border);
    text-align: left;
  }
  .not-cheating-box p { font-size: 1.02rem; margin-bottom: 18px; color: var(--text-secondary); }
  .not-cheating-box p:last-child { margin-bottom: 0; }
  .not-cheating-box strong { color: var(--text); }

  /* ── How It Works ── */
  .how-it-works { padding: 96px 0; }
  .steps-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 40px; margin-top: 40px; }
  .step-card { text-align: center; }
  .step-num {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 44px;
    height: 44px;
    border-radius: 50%;
    background: var(--btn-bg);
    color: var(--btn-text);
    font-weight: 700;
    font-size: 1.1rem;
    margin-bottom: 20px;
  }
  .step-card h3 { margin-bottom: 8px; }
  .step-card p { color: var(--text-secondary); font-size: 0.9rem; }

  /* ── Features ── */
  .features { padding: 96px 0; background: var(--bg-secondary); }
  .features-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 20px; margin-top: 40px; }
  .feature-card { padding: 24px; background: var(--bg); border-radius: var(--radius); border: 1px solid var(--border); }
  .feature-card h3 { margin-bottom: 8px; }
  .feature-card p { color: var(--text-secondary); font-size: 0.9rem; }

  /* ── Interview Prep Kit ── */
  .interview-prep { padding: 96px 0; }
  .interview-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 48px; align-items: start; }
  .interview-features { display: flex; flex-direction: column; gap: 20px; }
  .interview-feature { display: flex; gap: 14px; align-items: start; }
  .interview-feature-icon {
    width: 36px; height: 36px; border-radius: 6px;
    background: var(--bg-secondary); border: 1px solid var(--border);
    display: flex; align-items: center; justify-content: center;
    flex-shrink: 0; font-size: 1.1rem;
  }
  .interview-preview {
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    overflow: hidden;
  }
  .interview-preview-header {
    background: var(--btn-bg);
    color: var(--btn-text);
    padding: 10px 20px;
    font-size: 0.8rem;
    font-weight: 600;
  }
  .interview-preview-body { padding: 20px; font-size: 0.82rem; }
  .interview-preview-section { margin-bottom: 16px; }
  .interview-preview-section:last-child { margin-bottom: 0; }
  .interview-preview-section h4 { font-size: 0.78rem; color: var(--text-muted); margin-bottom: 6px; font-weight: 600; text-transform: uppercase; letter-spacing: 0.04em; }
  .interview-preview-section p,
  .interview-preview-section li { color: var(--text-secondary); }
  .interview-preview-section ul { padding-left: 16px; margin: 0; }

  /* ── Comparison Table ── */
  .comparison { padding: 96px 0; background: var(--bg-secondary); }
  .comparison-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.85rem;
    min-width: 700px;
    margin-top: 40px;
  }
  .comparison-table thead tr { border-bottom: 2px solid var(--border); }
  .comparison-table th {
    text-align: left;
    padding: 12px 16px;
    font-weight: 600;
    color: var(--text-muted);
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.04em;
  }
  .comparison-table th.highlight { color: var(--text); font-weight: 700; }
  .comparison-table td { padding: 12px 16px; border-bottom: 1px solid var(--border); }
  .comparison-table td.highlight { font-weight: 600; }
  .comparison-table td.feature-name { font-weight: 600; }
  .comparison-table .check { color: var(--success); font-weight: 600; }
  .comparison-table .cross { color: var(--danger); }
  .comparison-table .partial { color: #b45309; }

  /* ── Pricing ── */
  .pricing { padding: 96px 0; }
  .pricing-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; margin-top: 40px; max-width: 800px; margin-left: auto; margin-right: auto; }
  .price-card { text-align: center; padding: 32px 24px; border-radius: var(--radius); border: 1px solid var(--border); }
  .price-card.featured { border-color: var(--text); position: relative; }
  .price-card.featured::before {
    content: 'POPULAR';
    position: absolute; top: -11px; left: 50%; transform: translateX(-50%);
    background: var(--btn-bg); color: var(--btn-text);
    font-size: 0.65rem; font-weight: 700; padding: 2px 12px;
    border-radius: var(--radius); letter-spacing: 0.05em;
  }
  .price-card .price { font-size: 2.4rem; font-weight: 700; margin: 12px 0; }
  .price-card .price-sub { font-size: 0.85rem; color: var(--text-secondary); }
  .price-card ul { list-style: none; text-align: left; margin: 20px 0; }
  .price-card li { padding: 5px 0; font-size: 0.9rem; color: var(--text-secondary); }
  .price-card li::before { content: '✓ '; color: var(--success); font-weight: 600; }

  /* ── FAQ ── */
  .faq { padding: 96px 0; background: var(--bg-secondary); }
  .faq-list { max-width: 680px; margin: 40px auto 0; }
  .faq-item { border-bottom: 1px solid var(--border); }
  .faq-q {
    padding: 18px 0;
    font-weight: 600;
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    user-select: none;
  }
  .faq-q::after { content: '+'; font-size: 1.3rem; color: var(--text-muted); transition: transform 0.2s; }
  .faq-item.open .faq-q::after { transform: rotate(45deg); }
  .faq-a { max-height: 0; overflow: hidden; transition: max-height 0.3s; color: var(--text-secondary); font-size: 0.95rem; line-height: 1.7; }
  .faq-item.open .faq-a { max-height: 200px; padding-bottom: 18px; }

  /* ── CTA Banner ── */
  .cta-banner {
    padding: 96px 0;
    background: var(--btn-bg);
    color: var(--btn-text);
    text-align: center;
  }
  .cta-banner h2 { color: var(--btn-text); margin-bottom: 16px; }
  .cta-banner p { color: var(--text-muted); font-size: 1.05rem; margin-bottom: 32px; max-width: 560px; margin-left: auto; margin-right: auto; }
  .cta-banner .btn {
    background: var(--btn-text);
    color: var(--btn-bg);
    font-weight: 700;
  }
  .cta-banner .btn:hover { opacity: 0.9; }

  /* ── Footer ── */
  footer { padding: 40px 0; border-top: 1px solid var(--border); text-align: center; color: var(--text-muted); font-size: 0.85rem; }
  footer a { color: var(--text-muted); }
  footer a:hover { color: var(--text); }

  /* ── Responsive ── */
  @media (max-width: 768px) {
    .hero-grid { grid-template-columns: 1fr; gap: 40px; }
    .funnel-steps { grid-template-columns: 1fr; gap: 12px; }
    .funnel-arrow { transform: rotate(90deg); padding: 0; }
    .stats-grid { grid-template-columns: repeat(2, 1fr); }
    .why-not-grid, .steps-grid, .features-grid, .pricing-grid { grid-template-columns: 1fr; }
    .interview-grid { grid-template-columns: 1fr; }
    .score-compare { flex-direction: column; gap: 12px; }
    .score-arrow { transform: rotate(90deg); }
    .nav-links { display: none; }
    .hero { padding: 64px 0 48px; }
  }