*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
  body { font-family: Georgia, 'Times New Roman', serif; background: #f5f2ed; color: #1a1a1a; min-height: 100vh; padding: 3rem 1rem; }
  .container { width: 100%; max-width: 620px; margin: 0 auto; }
  h1 { font-size: 28px; font-weight: normal; letter-spacing: -0.5px; margin-bottom: 0.25rem; color: #1a1a1a; }
  h2 { font-size: 20px; font-weight: normal; margin-bottom: 0.75rem; }
  .intro-lede { font-size: 18px; line-height: 1.7; color: #333; margin-bottom: 2rem; }
  .intro-body { font-size: 15px; line-height: 1.8; color: #444; margin-bottom: 1.4rem; }
  .intro-divider { border: none; border-top: 1px solid #ddd; margin: 2rem 0; }
  .dim-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; margin: 1.5rem 0 2rem; }
  .dim-card { background: #fff; border: 1px solid #ddd; border-radius: 4px; padding: 1rem 1.1rem; }
  .dim-card-title { font-size: 11px; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; font-weight: 600; letter-spacing: 1.2px; text-transform: uppercase; margin-bottom: 5px; }
  .dim-card-body { font-size: 13px; line-height: 1.6; color: #555; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; }
  .pull-quote { border-left: 2px solid #1a1a1a; margin: 1.75rem 0; padding: 0.25rem 0 0.25rem 1.25rem; font-size: 17px; line-height: 1.65; color: #333; font-style: italic; }
  .start-btn { display: block; width: 100%; background: #1a1a1a; color: #f5f2ed; border: none; border-radius: 3px; padding: 14px; font-size: 15px; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; cursor: pointer; letter-spacing: 0.3px; margin-top: 0.5rem; transition: background 0.15s; }
  .start-btn:hover { background: #333; }
  .progress-wrap { display: flex; align-items: center; gap: 12px; margin-bottom: 2rem; }
  .progress-bar { flex: 1; height: 2px; background: #d8d4cc; border-radius: 1px; }
  .progress-fill { height: 2px; background: #1a1a1a; border-radius: 1px; transition: width 0.4s ease; }
  .progress-label { font-size: 12px; color: #666; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; white-space: nowrap; }
  .dim-badge { display: inline-block; font-size: 10px; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; font-weight: 600; letter-spacing: 1.5px; text-transform: uppercase; padding: 3px 10px; border-radius: 2px; margin-bottom: 1rem; }
  .alt-btn { background: transparent; border: none; font-size: 13px; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; color: #666; cursor: pointer; padding: 0; text-decoration: underline; text-underline-offset: 3px; } .alt-btn:hover { color: #1a1a1a; } .alt-btn:disabled { color: #999; cursor: default; text-decoration: none; }
  .report-section { margin-top: 2rem; padding-top: 2rem; border-top: 1px solid #ddd; }
  .report-btn { display: block; width: 100%; background: #1a1a1a; color: #f5f2ed; border: none; border-radius: 3px; padding: 14px; font-size: 15px; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; cursor: pointer; letter-spacing: 0.3px; transition: background 0.15s; }
  .report-btn:hover { background: #333; }
  .report-btn:disabled { background: #888; cursor: default; }
  .report-loading { display: none; text-align: center; padding: 2rem 0; }
  .report-spinner { width: 24px; height: 24px; border: 2px solid #ddd; border-top-color: #1a1a1a; border-radius: 50%; animation: spin 0.8s linear infinite; margin: 0 auto 1rem; }
  @keyframes spin { to { transform: rotate(360deg); } }
  .report-loading-text { font-size: 14px; color: #666; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; }
  .report-output { display: none; }
  .report-section-title { font-size: 10px; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; font-weight: 600; letter-spacing: 1.5px; text-transform: uppercase; color: #666; margin-bottom: 10px; }
  .report-para { font-size: 15px; line-height: 1.85; color: #333; margin-bottom: 1.2rem; }
  .report-para:last-child { margin-bottom: 0; }
  .report-card { background: #fff; border: 1px solid #ddd; border-radius: 4px; padding: 1.25rem 1.5rem; margin-bottom: 12px; }
  .report-error { font-size: 14px; color: #c0622a; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; padding: 1rem 0; display: none; }
  .q-text { font-size: 20px; line-height: 1.55; margin-bottom: 1.75rem; color: #1a1a1a; }
  .options { display: flex; flex-direction: column; gap: 10px; margin-bottom: 2rem; }
  .opt-btn { background: #fff; border: 1px solid #ddd; border-radius: 4px; padding: 14px 18px; font-size: 15px; font-family: Georgia, 'Times New Roman', serif; color: #1a1a1a; cursor: pointer; text-align: left; transition: border-color 0.15s, background 0.15s; line-height: 1.5; }
  .opt-btn:hover { border-color: #777; background: #faf9f7; }
  .opt-btn.selected { border-color: #1a1a1a; background: #1a1a1a; color: #f5f2ed; }
  .nav { display: flex; justify-content: space-between; align-items: center; }
  .nav-btn { background: transparent; border: 1px solid #ccc; border-radius: 3px; padding: 9px 22px; font-size: 13px; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; cursor: pointer; color: #1a1a1a; transition: background 0.15s; letter-spacing: 0.3px; }
  .nav-btn:hover { background: #eee; }
  .nav-btn:disabled { opacity: 0.3; cursor: default; }
  .nav-btn.primary { background: #1a1a1a; color: #f5f2ed; border-color: #1a1a1a; }
  .nav-btn.primary:hover { background: #333; }
  .result-card { background: #fff; border: 1px solid #ddd; border-radius: 4px; padding: 1.25rem 1.5rem; margin-bottom: 12px; }
  .result-card-label { font-size: 10px; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; font-weight: 600; letter-spacing: 1.5px; text-transform: uppercase; color: #666; margin-bottom: 10px; }
  .type-display { font-size: 64px; font-weight: normal; letter-spacing: -2px; line-height: 1; margin-bottom: 0.5rem; color: #1a1a1a; }
  .type-name { font-size: 14px; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; color: #666; margin-bottom: 1.5rem; }
  .dim-row { margin-bottom: 14px; }
  .dim-row:last-child { margin-bottom: 0; }
  .dim-row-labels { display: flex; justify-content: space-between; font-size: 12px; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; color: #666; margin-bottom: 5px; }
  .dim-track { height: 3px; background: #eee; border-radius: 2px; position: relative; overflow: hidden; }
  .dim-fill { height: 3px; border-radius: 2px; transition: width 0.6s ease, left 0.6s ease; position: absolute; top: 0; }
  .dim-result { font-size: 12px; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; color: #555; margin-top: 4px; text-align: center; }
  .action-btn { width: 100%; margin-top: 10px; padding: 12px; background: transparent; border: 1px solid #ccc; border-radius: 3px; font-size: 14px; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; cursor: pointer; color: #1a1a1a; transition: background 0.15s; }
  .action-btn:hover { background: #eee; }
  .action-btn.dark { background: #1a1a1a; color: #f5f2ed; border-color: #1a1a1a; }
  .action-btn.dark:hover { background: #333; }
  .neutral-card { border-left: 3px solid #ccc; border-radius: 0 4px 4px 0; }
  .click-card { border-left: 3px solid #2a7a4a; border-radius: 0 4px 4px 0; }
  .friction-card { border-left: 3px solid #c0622a; border-radius: 0 4px 4px 0; }
  .compat-pair { display: flex; align-items: center; gap: 12px; margin-bottom: 1.5rem; }
  .compat-type-badge { font-size: 36px; font-weight: normal; letter-spacing: -1px; color: #1a1a1a; min-width: 80px; text-align: center; }
  .compat-type-label { font-size: 12px; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; color: #666; text-align: center; margin-top: 4px; }
  .compat-vs { font-size: 16px; color: #888; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; }
  .compat-section-title { font-size: 10px; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; font-weight: 600; letter-spacing: 1.5px; text-transform: uppercase; color: #666; margin-bottom: 8px; }
  .compat-insight { font-size: 15px; line-height: 1.8; color: #333; }
  .notice-box { background: #fff8f0; border: 1px solid #e8d5b0; border-radius: 4px; padding: 1rem 1.25rem; margin-bottom: 1.5rem; font-size: 14px; line-height: 1.7; color: #5a4020; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; }
  .other-name-input { width: 100%; border: 1px solid #ddd; border-radius: 4px; padding: 12px 14px; font-size: 16px; font-family: Georgia, 'Times New Roman', serif; background: #fff; color: #1a1a1a; margin-bottom: 1rem; }
  .other-name-input:focus { outline: none; border-color: #666; }
  .part-label { font-size: 12px; color: #777; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; margin-bottom: 1.25rem; letter-spacing: 0.5px; text-transform: uppercase; }
  @media (max-width: 480px) { .dim-grid { grid-template-columns: 1fr; } .type-display { font-size: 48px; } .compat-type-badge { font-size: 28px; min-width: 64px; } }
  .invite-box { background: #fff; border: 1px solid #ddd; border-radius: 4px; padding: 1.5rem; margin-top: 2rem; }
  .invite-box h2 { font-size: 20px; font-weight: normal; margin-bottom: 0.75rem; }
  .invite-desc { font-size: 15px; line-height: 1.8; color: #444; margin-bottom: 1.25rem; }
  .invite-link-wrap { display: flex; gap: 8px; margin-bottom: 1rem; }
  .invite-link-input { flex: 1; border: 1px solid #ddd; border-radius: 3px; padding: 10px 12px; font-size: 13px; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; color: #555; background: #f9f9f6; }
  .copy-btn { background: #1a1a1a; color: #f5f2ed; border: none; border-radius: 3px; padding: 10px 16px; font-size: 13px; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; cursor: pointer; white-space: nowrap; }
  .copy-btn:hover { background: #333; }
  .copy-confirm { font-size: 12px; color: #2a7a4a; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; display: none; margin-top: 4px; }
  .userb-banner { background: #e8f0fb; border: 1px solid #6fa8dc; border-radius: 4px; padding: 1rem 1.25rem; margin-bottom: 1.5rem; font-size: 14px; line-height: 1.7; color: #1a3a6a; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; }
  .compat-link-box { background: #e6f5ee; border: 1px solid #2a7a4a; border-radius: 4px; padding: 1.25rem; margin-top: 1.5rem; }
  .compat-link-box p { font-size: 14px; line-height: 1.7; color: #1a5c3a; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; margin-bottom: 0.75rem; }
  /* ── LANDING PAGE ── */
  .lesson-banner { display:none; background:#1a2744; color:#fdfcfa; font-family:'Helvetica Neue',Arial,sans-serif; font-size:13px; font-weight:600; letter-spacing:0.3px; padding:10px 16px; margin:0 0 1.25rem; border-radius:4px; text-align:center; }
  .course-directory { background:#f8f5ef; border:1px solid #e0d8cc; border-radius:6px; padding:1.25rem; margin:1.5rem 0; }
  .course-directory-title { font-size:11px; font-family:'Helvetica Neue',Arial,sans-serif; font-weight:600; letter-spacing:1.5px; text-transform:uppercase; color:#666; margin-bottom:10px; }
  .course-directory ol { margin:0; padding-left:1.2rem; }
  .course-directory li { font-size:14px; font-family:'Helvetica Neue',Arial,sans-serif; color:#333; margin-bottom:8px; line-height:1.5; }
  .course-directory li.locked { color:#999; }
  .course-directory a { color:#1a2744; text-decoration:underline; cursor:pointer; }
  .course-directory a:hover { color:#c8a96e; }

  .landing-hero { text-align: center; padding: 2rem 0 1rem; }
  .landing-logo { font-size: 11px; letter-spacing: 3px; text-transform: uppercase; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; color: #666; margin-bottom: 2.5rem; }
  .landing-h1 { font-size: 36px; font-weight: normal; letter-spacing: -1px; line-height: 1.2; margin-bottom: 1rem; color: #1a1a1a; }
  .landing-sub { font-size: 17px; line-height: 1.7; color: #555; margin-bottom: 2rem; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; }
  .price-badge { display: inline-block; background: #1a1a1a; color: #f5f2ed; font-size: 13px; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; padding: 5px 14px; border-radius: 2px; margin-bottom: 2rem; letter-spacing: 0.3px; }
  .landing-cta { display: block; width: 100%; background: #1a1a1a; color: #f5f2ed; border: none; border-radius: 3px; padding: 16px; font-size: 16px; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; cursor: pointer; letter-spacing: 0.3px; transition: background 0.15s; margin-bottom: 0.75rem; }
  .landing-cta:hover { background: #333; }
  .landing-free-link { font-size: 13px; color: #666; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; text-align: center; cursor: pointer; text-decoration: underline; text-underline-offset: 3px; background: none; border: none; width: 100%; padding: 4px 0; }
  .landing-free-link:hover { color: #1a1a1a; }
  .feature-list { list-style: none; margin: 2.5rem 0; }
  .feature-list li { display: flex; gap: 12px; align-items: flex-start; padding: 12px 0; border-bottom: 1px solid #eee; font-size: 15px; color: #333; line-height: 1.6; }
  .feature-list li:first-child { border-top: 1px solid #eee; }
  .feature-icon { flex-shrink: 0; width: 20px; height: 20px; background: #1a1a1a; border-radius: 50%; display: flex; align-items: center; justify-content: center; margin-top: 2px; }
  .feature-icon svg { width: 10px; height: 10px; }
  .testimonial-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; margin: 2rem 0; }
  .testimonial { background: #fff; border: 1px solid #ddd; border-radius: 4px; padding: 1rem 1.1rem; }
  .testimonial-text { font-size: 14px; line-height: 1.65; color: #444; margin-bottom: 8px; font-style: italic; }
  .testimonial-name { font-size: 11px; color: #666; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; font-weight: 600; letter-spacing: 0.5px; text-transform: uppercase; }
  .guarantee { background: #f9f9f6; border: 1px solid #ddd; border-radius: 4px; padding: 1rem 1.25rem; margin: 1.5rem 0; font-size: 14px; line-height: 1.7; color: #444; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; }
  .guarantee strong { color: #1a1a1a; }
  .landing-divider { border: none; border-top: 1px solid #ddd; margin: 2.5rem 0; }
  /* ── PAYWALL ── */
  .paywall-section { margin-top: 2rem; padding: 1.5rem; background: #fff; border: 1px solid #ddd; border-radius: 4px; text-align: center; }
  .paywall-lock { font-size: 28px; margin-bottom: 0.75rem; }
  .paywall-title { font-size: 20px; font-weight: normal; margin-bottom: 0.5rem; color: #1a1a1a; }
  .paywall-desc { font-size: 14px; line-height: 1.7; color: #666; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; margin-bottom: 1.25rem; }
  .paywall-features { text-align: left; list-style: none; margin-bottom: 1.5rem; }
  .paywall-features li { font-size: 14px; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; color: #444; padding: 4px 0; display: flex; gap: 8px; }
  .paywall-features li::before { content: "✓"; color: #2a7a4a; font-weight: 600; flex-shrink: 0; }
  .paywall-btn { display: block; width: 100%; background: #1a1a1a; color: #f5f2ed; border: none; border-radius: 3px; padding: 14px; font-size: 15px; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; cursor: pointer; letter-spacing: 0.3px; transition: background 0.15s; margin-bottom: 8px; }
  .paywall-btn:hover { background: #333; }
  .paywall-note { font-size: 12px; color: #777; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; }
  .unlocked-badge { display: inline-flex; align-items: center; gap: 6px; background: #e6f5ee; color: #1a5c3a; font-size: 12px; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; font-weight: 600; letter-spacing: 0.5px; padding: 4px 10px; border-radius: 2px; margin-bottom: 1rem; text-transform: uppercase; }
  @media (max-width: 480px) { .testimonial-grid { grid-template-columns: 1fr; } .landing-h1 { font-size: 28px; } }

  .install-banner {
    display: none;
    position: fixed;
    bottom: 1rem;
    left: 50%;
    transform: translateX(-50%);
    background: #1a1a1a;
    color: #f5f2ed;
    border-radius: 8px;
    padding: 1rem 1.25rem;
    box-shadow: 0 4px 24px rgba(0,0,0,0.3);
    z-index: 9999;
    width: calc(100% - 2rem);
    max-width: 400px;
    font-family: 'Helvetica Neue', Arial, sans-serif;
    align-items: center;
    gap: 1rem;
  }
  .install-banner.show { display: flex; }
  .install-banner-text { flex: 1; font-size: 13px; line-height: 1.5; }
  .install-banner-text strong { display: block; margin-bottom: 2px; font-size: 14px; }
  .install-banner-btn { background: #c8a96e; color: #1a1a1a; border: none; border-radius: 4px; padding: 8px 14px; font-size: 13px; font-weight: 600; cursor: pointer; white-space: nowrap; }
  .install-banner-dismiss { background: none; border: none; color: rgba(253,252,250,0.5); font-size: 18px; cursor: pointer; padding: 0; line-height: 1; flex-shrink: 0; }

  .coming-soon-wrap { background: #f5edd8; border: 1px solid #c8a96e; border-radius: 6px; padding: 1.25rem; margin: 0.5rem 0; text-align: center; }
  .coming-soon-title { font-size: 15px; font-weight: normal; color: #1a2744; margin-bottom: 0.5rem; font-family: Georgia, serif; }
  .coming-soon-sub { font-size: 13px; color: #555; font-family: 'Helvetica Neue', Arial, sans-serif; margin-bottom: 0.75rem; }
  .coming-soon-form { display: flex; gap: 8px; max-width: 360px; margin: 0 auto; flex-wrap: wrap; justify-content: center; }
  .coming-soon-input { flex: 1; min-width: 180px; border: 1px solid #c8a96e; border-radius: 3px; padding: 10px 12px; font-size: 14px; font-family: 'Helvetica Neue', Arial, sans-serif; color: #333; background: white; }
  .coming-soon-input:focus { outline: none; border-color: #1a2744; }
  .coming-soon-btn { background: #1a2744; color: #f5f2ed; border: none; border-radius: 3px; padding: 10px 16px; font-size: 13px; font-family: 'Helvetica Neue', Arial, sans-serif; font-weight: 600; cursor: pointer; white-space: nowrap; }
  .coming-soon-btn:hover { background: #243560; }
  .coming-soon-confirm { font-size: 13px; color: #2a7a4a; font-family: 'Helvetica Neue', Arial, sans-serif; margin-top: 0.5rem; display: none; }
  .coming-soon-wrap, .coming-soon-form, .coming-soon-input, .coming-soon-btn { display: none !important; }


/* ── LESSON NAVIGATION ADDITIONS ── */
.lesson-cta-box {
  background: #1a2744;
  border-radius: 8px;
  padding: 1.75rem;
  margin: 1.75rem 0;
  text-align: center;
}
.lesson-cta-eyebrow {
  font-size: 11px;
  font-family: 'Helvetica Neue', Arial, sans-serif;
  letter-spacing: 2px;
  text-transform: uppercase;
  color: #c8a96e;
  margin-bottom: 0.6rem;
}
.lesson-cta-title {
  font-size: 19px;
  font-weight: normal;
  color: #fdfcfa;
  margin-bottom: 0.75rem;
}
.lesson-cta-body {
  font-size: 14px;
  color: rgba(253,252,250,0.8);
  font-family: 'Helvetica Neue', Arial, sans-serif;
  line-height: 1.7;
  margin-bottom: 1.25rem;
}
.lesson-cta-btn {
  display: inline-block;
  background: #c8a96e;
  color: #1a1a1a;
  border-radius: 4px;
  padding: 11px 24px;
  font-family: 'Helvetica Neue', Arial, sans-serif;
  font-size: 14px;
  font-weight: 600;
  text-decoration: none;
}
.lesson-breadcrumb {
  text-align: center;
  font-size: 12px;
  font-family: 'Helvetica Neue', Arial, sans-serif;
  color: #999;
  margin: 0 0 1.25rem;
}
.lesson-breadcrumb a {
  color: #999;
  text-decoration: underline;
}
.lesson-breadcrumb a:hover {
  color: #c8a96e;
}
.lesson-breadcrumb .current {
  color: #1a2744;
  font-weight: 600;
  text-decoration: none;
}