:root {
    /* TechSyntar tone — warm cream canvas, white cards, red + blue accents (whole app) */
    --navy: #FBF3EA;        /* cream page / app background */
    --navy-mid: #FFFFFF;    /* white panel (selects, inputs) */
    --navy-light: #F3EADF;  /* warm raised panel */
    --teal: #2F6BF0;        /* PRIMARY brand blue */
    --teal-dark: #1E4FC4;
    --gold: #E0313D;        /* SECONDARY brand red */
    --gold-light: #FF6B74;
    --white: #14233F;       /* primary INK text */
    --gray-light: #4F5E78;  /* body text */
    --gray-mid: #8090A8;    /* muted text */
    --red-accent: #E0313D;
    --green-accent: #15A34A;
    --purple-accent: #5B57E0;
    --ink: #14233F;
    --ink-soft: #51607A;
    --page: #FBF3EA;        /* warm cream */
    --line: #EBE1D4;        /* warm border */
    --week1: #2F6BF0;
    --week2: #E0313D;
    --week3: #5B57E0;
    --week4: #C0202C;
    --week5: #1E4FC4;
    --week6: #9F1239;
  }

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

  body {
    font-family: 'Inter', sans-serif;
    background: var(--navy);
    color: var(--white);
    overflow: hidden;
    height: 100vh;
    width: 100vw;
    user-select: none;
    -webkit-font-smoothing: antialiased;
  }

  /* ===== SIDEBAR ===== */
  #sidebar {
    position: fixed;
    left: 0; top: 0;
    width: 220px;
    height: 100vh;
    background: #FFFFFF;
    border-right: 1px solid var(--line);
    box-shadow: 1px 0 0 rgba(17,32,59,0.03);
    z-index: 100;
    display: flex;
    flex-direction: column;
    overflow: hidden;
    transition: width 0.3s ease;
  }
  #sidebar.collapsed { width: 56px; }

  .sidebar-logo {
    padding: 16px 16px;
    border-bottom: 1px solid rgba(61,123,247,0.1);
    display: flex; align-items: center; gap: 10px;
    flex-shrink: 0;
  }
  .logo-mark {
    width: 36px; height: 36px; border-radius: 8px;
    background: #fff;
    display: flex; align-items: center; justify-content: center;
    flex-shrink: 0;
    overflow: hidden;
    padding: 2px;
  }
  .logo-mark img { width: 100%; height: 100%; object-fit: contain; }
  .logo-text { font-size: 10px; font-weight: 600; color: var(--teal); letter-spacing: 0.05em; line-height: 1.3; }
  #sidebar.collapsed .logo-text { display: none; }

  .session-list {
    flex: 1; overflow-y: auto; padding: 8px 0;
    scrollbar-width: thin;
    scrollbar-color: var(--teal) transparent;
  }

  .week-group { margin-bottom: 4px; }
  .week-label {
    font-size: 9px; font-weight: 700; letter-spacing: 0.12em;
    padding: 8px 14px 4px;
    text-transform: uppercase;
    transition: opacity 0.3s;
  }
  #sidebar.collapsed .week-label { opacity: 0; }

  .session-btn {
    display: flex; align-items: center; gap: 10px;
    padding: 7px 14px;
    cursor: pointer;
    border: none; background: transparent;
    color: var(--gray-light);
    width: 100%; text-align: left;
    font-family: 'Inter', sans-serif;
    font-size: 11px; font-weight: 500;
    transition: all 0.2s;
    position: relative;
  }
  .session-btn:hover { background: rgba(61,123,247,0.07); color: var(--white); }
  .session-btn.active { background: rgba(61,123,247,0.12); color: var(--teal); }
  .session-btn.active::before {
    content: ''; position: absolute; left: 0; top: 0; bottom: 0;
    width: 3px; background: var(--teal); border-radius: 0 2px 2px 0;
  }
  .s-dot {
    width: 22px; height: 22px; border-radius: 50%;
    display: flex; align-items: center; justify-content: center;
    font-size: 9px; font-weight: 700; flex-shrink: 0;
    border: 1.5px solid currentColor;
    transition: all 0.2s;
  }
  .session-btn.active .s-dot { background: var(--teal); border-color: var(--teal); color: var(--navy); }
  .s-title { line-height: 1.3; }
  #sidebar.collapsed .s-title { display: none; }
  #sidebar.collapsed .week-label { display: none; }

  /* ===== SIDEBAR AUTHOR ===== */
  .sidebar-author {
    flex-shrink: 0;
    padding: 14px 16px 16px;
    border-top: 1px solid rgba(61,123,247,0.12);
    background: rgba(61,123,247,0.03);
    transition: opacity 0.2s;
  }
  .author-name {
    font-family: 'Playfair Display', serif;
    font-size: 13px; font-weight: 700; color: var(--white);
    line-height: 1.25; margin-bottom: 5px;
  }
  .author-tags {
    font-size: 9.5px; font-weight: 600; letter-spacing: 0.03em;
    color: var(--teal); text-transform: uppercase;
    line-height: 1.4; margin-bottom: 7px;
  }
  .author-bio {
    font-size: 10px; font-weight: 400; color: var(--gray-mid);
    line-height: 1.45;
  }
  #sidebar.collapsed .sidebar-author { opacity: 0; pointer-events: none; padding: 0; height: 0; overflow: hidden; }

  /* ===== SIDE MAP — its own identity: deep-navy panel, week colors pop ===== */
  #sidebar {
    background: linear-gradient(180deg, #11264C 0%, #0A1A33 100%) !important;
    border-right: 1px solid rgba(47,107,240,0.22) !important;
    box-shadow: 2px 0 20px -8px rgba(10,22,40,0.5) !important;
  }
  #sidebar .sidebar-logo { border-bottom: 1px solid rgba(255,255,255,0.10); }
  #sidebar .logo-text { color: #AFC6FF; }
  #sidebar .session-list { scrollbar-color: rgba(255,255,255,0.28) transparent; }
  #sidebar .week-label { color: #7E8FB3; }
  #sidebar .session-btn { color: #B4C2DA; }
  #sidebar .session-btn:hover { background: rgba(255,255,255,0.07); color: #FFFFFF; }
  #sidebar .session-btn.active { background: rgba(47,107,240,0.24); color: #FFFFFF; }
  #sidebar .session-btn.active .s-dot { color: #0A1A33; }
  #sidebar .sidebar-author {
    border-top: 1px solid rgba(255,255,255,0.10);
    background: rgba(255,255,255,0.035);
  }
  #sidebar .author-name { color: #F4F7FC; }
  #sidebar .author-tags { color: #8FB0FF; }
  #sidebar .author-bio { color: #9AA8C2; }
  #sidebar .sidebar-toggle {
    background: #11264C; border: 1px solid rgba(47,107,240,0.5); color: #AFC6FF;
  }

  .sidebar-toggle {
    position: absolute; right: -12px; top: 50%;
    transform: translateY(-50%);
    width: 24px; height: 24px; border-radius: 50%;
    background: var(--navy-mid); border: 1px solid rgba(61,123,247,0.3);
    cursor: pointer; display: flex; align-items: center; justify-content: center;
    color: var(--teal); font-size: 10px; z-index: 101;
    transition: all 0.2s;
  }
  .sidebar-toggle:hover { background: var(--teal); color: var(--navy); }

  /* ===== MAIN STAGE ===== */
  #stage {
    margin-left: 220px;
    height: 100vh;
    position: relative;
    transition: margin-left 0.3s ease;
    display: flex; flex-direction: column;
  }
  body.sidebar-collapsed #stage { margin-left: 56px; }

  /* Progress bar */
  #progress-bar {
    height: 3px;
    background: rgba(20,35,63,0.10);
    position: relative; flex-shrink: 0;
  }
  #progress-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--teal), var(--gold));
    transition: width 0.4s ease;
    border-radius: 0 2px 2px 0;
  }

  /* Top bar */
  #topbar {
    display: flex; align-items: center; justify-content: space-between;
    padding: 10px 24px;
    border-bottom: 1px solid rgba(20,35,63,0.10);
    flex-shrink: 0;
  }
  .session-badge {
    display: flex; align-items: center; gap: 10px;
  }
  .week-chip {
    padding: 3px 10px; border-radius: 20px;
    font-size: 10px; font-weight: 700; letter-spacing: 0.08em;
    text-transform: uppercase;
  }
  .session-title-top {
    font-size: 13px; font-weight: 600; color: var(--white);
    max-width: 420px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap;
  }
  #slide-jump {
    width: 42px; text-align: center; font-family: 'JetBrains Mono', monospace;
    font-size: 12px; font-weight: 600; color: var(--ink);
    background: #fff; border: 1px solid var(--line); border-radius: 6px; padding: 2px 4px;
  }
  #slide-jump:focus { outline: none; border-color: var(--teal); box-shadow: 0 0 0 2px rgba(47,107,240,0.15); }

  /* ===== TOP-BAR TOOLS: search · slide jump · fullscreen ===== */
  .topbar-tools { display: flex; align-items: center; gap: 14px; }
  .search-wrap { position: relative; display: flex; align-items: center; }
  .search-wrap .search-ico { position: absolute; left: 10px; font-size: 12px; opacity: 0.6; pointer-events: none; }
  #deep-search {
    width: 230px; max-width: 40vw; padding: 7px 26px 7px 30px;
    border: 1px solid var(--line); border-radius: 20px; background: #fff;
    font-family: 'Inter', sans-serif; font-size: 12.5px; color: var(--ink);
    transition: border-color .15s, box-shadow .15s, width .2s;
  }
  #deep-search::placeholder { color: var(--gray-mid); }
  #deep-search:focus { outline: none; border-color: var(--teal); box-shadow: 0 0 0 3px rgba(47,107,240,0.12); width: 300px; }
  #search-clear {
    position: absolute; right: 8px; border: none; background: transparent; cursor: pointer;
    color: var(--gray-mid); font-size: 12px; line-height: 1; padding: 2px;
  }
  #search-clear:hover { color: var(--gold); }
  #search-results {
    position: absolute; top: calc(100% + 8px); right: 0; width: 380px; max-width: 86vw;
    max-height: 60vh; overflow-y: auto; background: #fff; border: 1px solid var(--line);
    border-radius: 12px; box-shadow: 0 18px 44px -14px rgba(17,32,59,0.4); z-index: 140; padding: 6px;
  }
  .search-meta { padding: 8px 12px 6px; font-size: 11px; font-weight: 600; color: var(--gray-mid); }
  .search-result-item {
    display: flex; gap: 11px; align-items: flex-start; padding: 9px 11px; border-radius: 9px;
    cursor: pointer; transition: background .12s;
  }
  .search-result-item:hover, .search-result-item.kbd-active { background: var(--page); }
  .sr-badge {
    flex-shrink: 0; min-width: 30px; height: 30px; padding: 0 7px; border-radius: 8px; color: #fff;
    display: flex; align-items: center; justify-content: center; font-family: 'JetBrains Mono', monospace;
    font-size: 11px; font-weight: 700;
  }
  .sr-body { min-width: 0; }
  .sr-title { font-size: 12.5px; font-weight: 700; color: var(--ink); line-height: 1.25; }
  .sr-sub { font-size: 11px; color: var(--gray-mid); margin-top: 1px; }
  .sr-snippet { font-size: 11.5px; color: var(--ink-soft); line-height: 1.4; margin-top: 3px; }
  .sr-snippet mark { background: rgba(47,107,240,0.18); color: var(--teal-dark); border-radius: 3px; padding: 0 2px; }
  .search-empty { padding: 16px 12px; text-align: center; color: var(--gray-mid); font-size: 12.5px; }

  .tb-icon-btn {
    width: 34px; height: 34px; border-radius: 9px; border: 1px solid var(--line); background: #fff;
    color: var(--ink-soft); cursor: pointer; font-size: 15px; line-height: 1;
    display: flex; align-items: center; justify-content: center; transition: all .15s; flex-shrink: 0;
  }
  .tb-icon-btn:hover { border-color: var(--teal); color: var(--teal); }

  /* ===== MODULE read-aloud button ===== */
  .module-head { position: relative; }
  .mod-ra-btn {
    position: absolute; top: 0; right: 0;
    border: 1px solid var(--line); background: #fff; color: var(--ink);
    border-radius: 20px; padding: 7px 15px; font-family: 'Inter', sans-serif;
    font-size: 12px; font-weight: 600; cursor: pointer; display: inline-flex; align-items: center; gap: 7px;
    transition: all .15s;
  }
  .mod-ra-btn:hover { border-color: var(--teal); color: var(--teal); }
  .mod-ra-btn.reading { background: var(--gold); border-color: var(--gold); color: #fff; }

  .slide-counter {
    font-family: 'JetBrains Mono', monospace;
    font-size: 12px; color: var(--gray-mid);    display: flex; align-items: center; gap: 8px;
  }
  .slide-counter span { color: var(--teal); font-weight: 500; }

  /* ===== SLIDE CONTAINER ===== */
  #slide-container {
    flex: 1; overflow: hidden; position: relative;
  }

  .slide {
    position: absolute; inset: 0;
    display: none;
    padding: 40px 56px;
    overflow: hidden;
  }
  .slide.active { display: flex; flex-direction: column; }

  /* Slide types */
  .slide-cover {
    align-items: center; justify-content: center; text-align: center;
    background: radial-gradient(ellipse at 18% 12%, rgba(47,107,240,0.10) 0%, transparent 55%),
                radial-gradient(ellipse at 85% 88%, rgba(224,49,61,0.08) 0%, transparent 55%),
                radial-gradient(ellipse at 20% 50%, rgba(47,107,240,0.0) 0%, transparent 60%),
                radial-gradient(ellipse at 80% 20%, rgba(232,58,69,0.06) 0%, transparent 50%),
                var(--navy);
  }
  .slide-section-header {
    align-items: flex-start; justify-content: center;
    background: linear-gradient(135deg, var(--navy-mid) 0%, var(--navy) 100%);
  }
  .slide-content {
    background: var(--navy);
  }
  .slide-activity {
    background: linear-gradient(135deg, rgba(99,102,241,0.05) 0%, var(--navy) 60%);
  }
  .slide-summary {
    background: linear-gradient(135deg, rgba(61,123,247,0.05) 0%, var(--navy) 60%);
    align-items: center; justify-content: center; text-align: center;
  }

  /* Decorative accent line */
  .accent-bar {
    height: 3px; width: 60px; border-radius: 2px;
    margin: 16px 0;
  }
  .accent-bar.centered { margin: 16px auto; }

  /* Typography */
  .eyebrow {
    font-size: 11px; font-weight: 700; letter-spacing: 0.15em;
    text-transform: uppercase; margin-bottom: 12px;
  }
  .slide-h1 {
    font-family: 'Playfair Display', serif;
    font-size: clamp(2rem, 3.5vw, 3rem);
    font-weight: 900; line-height: 1.1;
    color: var(--white);
  }
  .slide-h2 {
    font-family: 'Playfair Display', serif;
    font-size: clamp(1.4rem, 2.5vw, 2rem);
    font-weight: 700; line-height: 1.2;
    color: var(--white);
  }
  .slide-h3 {
    font-family: 'Inter', sans-serif;
    font-size: 1.1rem; font-weight: 600;
    color: var(--white); margin-bottom: 8px;
  }
  .subtitle {
    font-size: 1rem; font-weight: 400;
    color: var(--gray-light); line-height: 1.6;
    margin-top: 12px;
  }
  .body-text {
    font-size: 0.9rem; color: var(--gray-light); line-height: 1.7;
  }

  /* Layouts */
  .two-col { display: grid; grid-template-columns: 1fr 1fr; gap: 32px; margin-top: 24px; }
  .three-col { display: grid; grid-template-columns: 1fr 1fr 1fr; gap: 20px; margin-top: 24px; }

  /* Cards */
  .card {
    background: #FFFFFF;
    border: 1px solid var(--line);
    border-radius: 14px; padding: 20px;
    box-shadow: 0 1px 2px rgba(17,32,59,0.04), 0 6px 18px -12px rgba(17,32,59,0.18);
    transition: border-color 0.2s, box-shadow 0.2s, transform 0.2s;
  }
  .card:hover { border-color: rgba(47,107,240,0.40); box-shadow: 0 2px 4px rgba(17,32,59,0.05), 0 14px 30px -16px rgba(17,32,59,0.22); transform: translateY(-1px); }
  .card-accent { border-top: 3px solid var(--teal); }
  .card-gold { border-top: 3px solid var(--gold); }
  .card-purple { border-top: 3px solid var(--purple-accent); }
  .card-green { border-top: 3px solid var(--green-accent); }

  /* Bullet lists */
  .bullet-list { list-style: none; margin-top: 12px; }
  .bullet-list li {
    display: flex; align-items: flex-start; gap: 10px;
    padding: 7px 0; font-size: 0.88rem; color: var(--gray-light);
    border-bottom: 1px solid #FFFFFF;
  }
  .bullet-list li:last-child { border-bottom: none; }
  .bullet-list li::before {
    content: '▸'; color: var(--teal); font-size: 10px;
    margin-top: 3px; flex-shrink: 0;
  }

  /* Output badges */
  .output-row { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 16px; }
  .output-badge {
    display: flex; align-items: center; gap: 6px;
    padding: 6px 12px; border-radius: 20px;
    background: rgba(61,123,247,0.1); border: 1px solid rgba(61,123,247,0.25);
    font-size: 11px; font-weight: 600; color: var(--teal);
  }
  .output-badge::before { content: '✓'; font-size: 10px; }

  /* PICO / framework boxes */
  .framework-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 12px; margin-top: 20px; }
  .framework-cell {
    background: #FFFFFF;
    border-radius: 10px; padding: 16px 12px; text-align: center;
    border-bottom: 3px solid var(--teal);
  }
  .framework-cell .letter {
    font-family: 'Playfair Display', serif;
    font-size: 2rem; font-weight: 900; color: var(--teal);
  }
  .framework-cell .label { font-size: 11px; font-weight: 600; color: var(--white); margin: 4px 0 2px; }
  .framework-cell .desc { font-size: 10px; color: var(--gray-mid); }

  /* Stat callouts */
  .stat-row { display: flex; gap: 20px; margin-top: 20px; }
  .stat-box {
    flex: 1; background: #FFFFFF; border-radius: 12px; padding: 18px;
    text-align: center; border: 1px solid var(--line);
  }
  .stat-num { font-family: 'Playfair Display', serif; font-size: 2.2rem; font-weight: 900; color: var(--teal); }
  .stat-label { font-size: 11px; color: var(--gray-mid); margin-top: 4px; }

  /* Timeline / process */
  .timeline { margin-top: 20px; }
  .timeline-step {
    display: flex; gap: 16px; padding: 12px 0;
    border-left: 2px solid rgba(61,123,247,0.2);
    padding-left: 20px; position: relative; margin-left: 10px;
  }
  .timeline-step::before {
    content: ''; position: absolute; left: -6px; top: 18px;
    width: 10px; height: 10px; border-radius: 50%;
    background: var(--teal); border: 2px solid var(--navy);
  }
  .timeline-step:last-child { border-left-color: transparent; }
  .step-num { font-family: 'JetBrains Mono', monospace; font-size: 10px; color: var(--teal); font-weight: 600; flex-shrink: 0; margin-top: 2px; }
  .step-content .step-title { font-size: 13px; font-weight: 600; color: var(--white); margin-bottom: 3px; }
  .step-content .step-desc { font-size: 11px; color: var(--gray-mid); line-height: 1.5; }

  /* Quote / highlight box */
  .highlight-box {
    background: linear-gradient(135deg, rgba(61,123,247,0.08), rgba(61,123,247,0.03));
    border-left: 4px solid var(--teal);
    border-radius: 0 12px 12px 0;
    padding: 16px 20px; margin-top: 20px;
    font-style: italic; color: var(--gray-light);
    font-size: 0.9rem; line-height: 1.6;
  }

  /* Comparison table */
  .comp-table { width: 100%; margin-top: 20px; border-collapse: collapse; }
  .comp-table th {
    background: rgba(61,123,247,0.1); padding: 10px 14px;
    font-size: 11px; font-weight: 700; text-align: left;
    border-bottom: 2px solid var(--teal); color: var(--teal);
    text-transform: uppercase; letter-spacing: 0.05em;
  }
  .comp-table td {
    padding: 9px 14px; font-size: 12px; color: var(--gray-light);
    border-bottom: 1px solid rgba(20,35,63,0.09);
  }
  .comp-table tr:hover td { background: rgba(20,35,63,0.05); }
  .tag {
    display: inline-block; padding: 2px 8px; border-radius: 10px;
    font-size: 10px; font-weight: 600;
  }
  .tag-good { background: rgba(34,197,94,0.15); color: var(--green-accent); }
  .tag-bad { background: rgba(232,58,69,0.15); color: var(--red-accent); }
  .tag-neutral { background: rgba(232,58,69,0.15); color: var(--gold); }

  /* Cover decorative */
  .cover-ornament {
    width: 120px; height: 120px; border-radius: 50%;
    background: radial-gradient(circle, rgba(61,123,247,0.15), transparent 70%);
    border: 1px solid rgba(61,123,247,0.2);
    display: flex; align-items: center; justify-content: center;
    margin: 0 auto 24px;
    position: relative;
  }
  .cover-ornament::before {
    content: ''; position: absolute; inset: 8px;
    border-radius: 50%; border: 1px dashed rgba(61,123,247,0.3);
  }
  .cover-icon { font-size: 2.5rem; }

  /* Big centered number */
  .big-num {
    font-family: 'Playfair Display', serif;
    font-size: 6rem; font-weight: 900;
    line-height: 1; color: transparent;
    background: linear-gradient(135deg, var(--teal), var(--gold));
    -webkit-background-clip: text; background-clip: text;
    margin-bottom: 8px;
  }

  /* Grid icon cards */
  .icon-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 14px; margin-top: 20px; }
  .icon-card {
    background: #FFFFFF; border-radius: 10px; padding: 16px;
    border: 1px solid var(--line);
    text-align: center;
  }
  .icon-card .ic-icon { font-size: 1.8rem; margin-bottom: 8px; }
  .icon-card .ic-title { font-size: 12px; font-weight: 600; color: var(--white); margin-bottom: 4px; }
  .icon-card .ic-desc { font-size: 10px; color: var(--gray-mid); line-height: 1.4; }

  /* Divider */
  .divider { border: none; border-top: 1px solid var(--line); margin: 16px 0; }

  /* Code-style box */
  .code-box {
    background: #11203B; border-radius: 10px; padding: 14px 18px;
    font-family: 'JetBrains Mono', monospace;
    font-size: 12px; color: #7FA8FF;
    border: 1px solid rgba(46,95,232,0.35); margin-top: 14px;
    line-height: 1.8;
  }
  .code-box .cm { color: #8392AE; }
  .code-box .cv { color: #F8A0A6; }
  .code-box .ck { color: #A5A3F7; }

  /* Checklist */
  .checklist { list-style: none; margin-top: 16px; }
  .checklist li {
    display: flex; align-items: center; gap: 10px;
    padding: 8px 0; font-size: 0.88rem; color: var(--gray-light);
  }
  .check-box {
    width: 18px; height: 18px; border-radius: 4px;
    border: 1.5px solid var(--teal); flex-shrink: 0;
    display: flex; align-items: center; justify-content: center;
    font-size: 10px; color: var(--teal);
  }

  /* ===== NAV CONTROLS ===== */
  #nav-controls {
    display: flex; align-items: center; justify-content: space-between;
    padding: 10px 24px; border-top: 1px solid rgba(20,35,63,0.10);
    flex-shrink: 0;
  }
  .nav-btn {
    display: flex; align-items: center; gap: 8px;
    padding: 8px 18px; border-radius: 8px; border: 1px solid rgba(61,123,247,0.3);
    background: rgba(61,123,247,0.05); cursor: pointer;
    font-family: 'Inter', sans-serif; font-size: 12px; font-weight: 600;
    color: var(--teal); transition: all 0.2s;
  }
  .nav-btn:hover { background: rgba(61,123,247,0.12); border-color: var(--teal); }
  .nav-btn:disabled { opacity: 0.3; cursor: default; }
  .nav-center { font-size: 11px; color: var(--gray-mid); text-align: center; }
  .keyboard-hint { font-family: 'JetBrains Mono', monospace; font-size: 10px; }
  .kbd { display: inline-block; padding: 1px 5px; border-radius: 3px; border: 1px solid rgba(20,35,63,0.22); color: var(--gray-light); }

  /* Animation */
  .slide.active { animation: slideIn 0.3s ease; }
  @keyframes slideIn { from { opacity: 0; transform: translateY(12px); } to { opacity: 1; transform: translateY(0); } }

  /* Scrollable slide content */
  .slide-scroll { overflow-y: auto; flex: 1; padding-right: 4px; scrollbar-width: thin; scrollbar-color: rgba(61,123,247,0.3) transparent; }

  /* ===== READ ALOUD ===== */
  #read-aloud-bar {
    display: flex; align-items: center; gap: 10px;
    padding: 9px 24px;
    border-top: 1px solid rgba(47,107,240,0.22);
    background: linear-gradient(180deg, #11264C 0%, #0A1A33 100%);
    flex-shrink: 0;
    flex-wrap: wrap;
  }
  .ra-btn {
    display: flex; align-items: center; gap: 6px;
    padding: 6px 14px; border-radius: 8px;
    border: 1px solid rgba(120,160,255,0.35);
    background: rgba(120,160,255,0.10); cursor: pointer;
    font-family: 'Inter', sans-serif; font-size: 12px; font-weight: 600;
    color: #AFC6FF; transition: all 0.2s;
  }
  .ra-btn:hover { background: rgba(120,160,255,0.20); color: #FFFFFF; }
  .ra-btn:disabled { opacity: 0.4; cursor: default; }
  .ra-btn.active { background: #3B82F6; border-color: #3B82F6; color: #FFFFFF; }
  #ra-voice-select {
    background: rgba(255,255,255,0.06); color: #E6EDFB;
    border: 1px solid rgba(120,160,255,0.30); border-radius: 8px;
    padding: 6px 10px; font-size: 11px; font-family: 'Inter', sans-serif;
    max-width: 220px; cursor: pointer;
  }
  #ra-rate-select {
    background: rgba(255,255,255,0.06); color: #E6EDFB;
    border: 1px solid rgba(120,160,255,0.30); border-radius: 8px;
    padding: 6px 8px; font-size: 11px; font-family: 'Inter', sans-serif;
    cursor: pointer;
  }
  #ra-voice-select option, #ra-rate-select option { color: #11203B; }
  #read-aloud-bar label { color: #9AB0D6 !important; }
  #read-aloud-bar input[type="checkbox"] { accent-color: #3B82F6; }
  .ra-status {
    font-size: 11px; color: #8FA3C8;
    font-family: 'JetBrains Mono', monospace;
    display: flex; align-items: center; gap: 6px;
    margin-left: auto;
  }
  .ra-status .ra-dot {
    width: 7px; height: 7px; border-radius: 50%;
    background: #6E82A8;
  }
  .ra-status.speaking { color: #CFE0FF; }
  .ra-status.speaking .ra-dot {
    background: #4D8DFF;
    animation: raPulse 1s infinite;
  }
  @keyframes raPulse { 0%,100%{opacity:1;} 50%{opacity:0.3;} }

  .ra-chunk-highlight {
    background: rgba(61,123,247,0.16) !important;
    box-shadow: 0 0 0 2px rgba(61,123,247,0.35);
    border-radius: 6px;
    transition: background 0.25s, box-shadow 0.25s;
  }

  /* IMRAD boxes */
  .imrad-row { display: flex; gap: 10px; margin-top: 20px; }
  .imrad-box {
    flex: 1; border-radius: 10px; padding: 14px;
    text-align: center; border-top: 3px solid;
  }
  .imrad-box .im-letter { font-family: 'Playfair Display', serif; font-size: 1.8rem; font-weight: 900; }
  .imrad-box .im-word { font-size: 11px; font-weight: 700; margin: 4px 0 2px; }
  .imrad-box .im-desc { font-size: 10px; color: var(--gray-mid); line-height: 1.4; }
  .imrad-I { background: rgba(61,123,247,0.08); border-color: var(--teal); color: var(--teal); }
  .imrad-M { background: rgba(99,102,241,0.08); border-color: var(--purple-accent); color: var(--purple-accent); }
  .imrad-R { background: rgba(34,197,94,0.08); border-color: var(--green-accent); color: var(--green-accent); }
  .imrad-A { background: rgba(232,58,69,0.08); border-color: var(--gold); color: var(--gold); }
  .imrad-D { background: rgba(232,58,69,0.08); border-color: var(--red-accent); color: var(--red-accent); }

  /* Cover decorations */
  .cover-grid {
    display: grid; grid-template-columns: repeat(3,1fr); gap: 12px;
    margin-top: 32px; max-width: 500px; width: 100%;
  }
  .cover-stat {
    background: #FFFFFF; border-radius: 10px; padding: 14px;
    border: 1px solid var(--line);
    text-align: center;
  }
  .cover-stat .cs-num { font-family: 'Playfair Display', serif; font-size: 1.6rem; font-weight: 900; color: var(--teal); }
  .cover-stat .cs-label { font-size: 10px; color: var(--gray-mid); margin-top: 2px; }

  /* Wide cover layout */
  .slide-cover { flex-direction: column; }

  /* ============================================================
     RESPONSIVE
     ============================================================ */

  /* Mobile chrome — hidden on desktop */
  #mobile-menu {
    display: none;
    position: fixed; top: 8px; left: 8px; z-index: 130;
    width: 40px; height: 40px; border-radius: 9px;
    align-items: center; justify-content: center;
    background: var(--navy-mid); color: var(--teal);
    border: 1px solid rgba(61,123,247,0.35);
    font-size: 18px; cursor: pointer; line-height: 1;
  }
  #mobile-menu:hover { background: var(--teal); color: var(--navy); }
  #sidebar-backdrop {
    display: none; position: fixed; inset: 0;
    background: rgba(5,10,24,0.6); z-index: 105;
    backdrop-filter: blur(2px);
  }

  /* ---- Tablet / small laptop ---- */
  @media (max-width: 1024px) {
    .slide { padding: 32px 36px; }
    .three-col { grid-template-columns: 1fr 1fr; }
    .icon-grid { grid-template-columns: 1fr 1fr; }
    .framework-grid { grid-template-columns: 1fr 1fr; }
    .two-col { gap: 24px; }
    .big-num { font-size: 4.5rem; }
    .session-title-top { max-width: 280px; }
  }

  /* ---- Mobile ---- */
  @media (max-width: 768px) {
    body { overflow: auto; }
    #mobile-menu { display: flex; }

    /* Sidebar becomes an off-canvas drawer */
    #sidebar {
      width: 82%; max-width: 320px;
      transform: translateX(0);
      transition: transform 0.3s ease;
      z-index: 110;
      box-shadow: 4px 0 24px rgba(0,0,0,0.4);
    }
    #sidebar.collapsed { width: 82%; max-width: 320px; transform: translateX(-100%); }
    #sidebar:not(.collapsed) { transform: translateX(0); }
    #sidebar.collapsed .logo-text,
    #sidebar.collapsed .s-title,
    #sidebar.collapsed .week-label,
    #sidebar.collapsed .sidebar-author { display: block; opacity: 1; height: auto; padding: revert; }
    #sidebar.collapsed .sidebar-author { padding: 14px 16px 16px; }
    .sidebar-toggle { display: none; }
    #sidebar-backdrop.show { display: block; }

    #stage { margin-left: 0; }
    body.sidebar-collapsed #stage { margin-left: 0; }

    /* Top bar makes room for the hamburger */
    #topbar { padding: 10px 14px 10px 58px; gap: 8px; }
    .session-title-top { max-width: 44vw; font-size: 12px; }
    .slide-counter { font-size: 11px; }

    /* Slides scroll vertically; clear the hamburger */
    .slide { padding: 56px 16px 20px; overflow-y: auto; overflow-x: auto; }
    .slide.active { display: flex; }

    /* Stack every multi-column layout */
    .two-col, .three-col, .icon-grid, .framework-grid { grid-template-columns: 1fr; gap: 14px; }
    .stat-row, .imrad-row { flex-direction: column; gap: 10px; }
    .timeline-step { padding-left: 16px; }

    .slide-h1 { font-size: clamp(1.6rem, 7vw, 2.2rem); }
    .slide-h2 { font-size: clamp(1.3rem, 5.5vw, 1.7rem); }
    .big-num { font-size: 3.2rem; }
    .cover-ornament { width: 88px; height: 88px; margin-bottom: 16px; }
    .cover-grid { grid-template-columns: 1fr 1fr; gap: 10px; margin-top: 20px; }

    /* Wide tables scroll inside their slide */
    .comp-table { min-width: 540px; }

    /* Read-aloud + nav adapt */
    #read-aloud-bar { padding: 8px 14px; gap: 8px; }
    #ra-voice-select { max-width: 150px; }
    #nav-controls { padding: 10px 14px; }
    .keyboard-hint { display: none; }
    .nav-btn { padding: 8px 14px; }
  }

  /* ---- Small phones ---- */
  @media (max-width: 480px) {
    .slide { padding: 56px 12px 18px; }
    .cover-grid { grid-template-columns: 1fr; }
    .session-title-top { display: none; }
    .nav-center { display: none; }
    #nav-controls { justify-content: space-between; }
    .big-num { font-size: 2.6rem; }
  }

  /* ============================================================
     INTERACTIVE MODULES (Explore / Quiz / Assignment) + rewards
     ============================================================ */
  #mode-bar {
    display: flex; align-items: center; justify-content: space-between; gap: 12px;
    padding: 9px 24px; background: #fff;
    border-bottom: 1px solid var(--line); flex-shrink: 0;
  }
  .mode-tabs {
    display: flex; gap: 3px; background: var(--page);
    border: 1px solid var(--line); border-radius: 12px; padding: 4px;
  }
  .mode-tab {
    border: none; background: transparent; padding: 8px 15px; border-radius: 9px;
    font-family: 'Inter', sans-serif; font-size: 12.5px; font-weight: 600;
    color: var(--ink-soft); cursor: pointer; display: flex; align-items: center; gap: 7px;
    transition: all .18s; white-space: nowrap; position: relative;
  }
  .mode-tab:hover { color: var(--ink); }
  .mode-tab.active { background: #fff; color: var(--teal); box-shadow: 0 1px 2px rgba(17,32,59,.07), 0 5px 14px -7px rgba(17,32,59,.3); }
  .mode-tab .pip {
    width: 7px; height: 7px; border-radius: 50%; background: var(--green-accent);
    display: none;
  }
  .mode-tab.has-progress .pip { display: inline-block; }

  .stars-badge {
    display: flex; align-items: center; gap: 6px;
    padding: 7px 14px; border-radius: 22px;
    background: linear-gradient(135deg, #FFF6DC, #FFE7A6);
    border: 1px solid #F3CE76; color: #93651A;
    font-weight: 800; font-size: 13px; flex-shrink: 0;
  }
  .stars-badge .star-ico { color: #F2A413; font-size: 15px; line-height: 1; }
  .stars-badge .stars-label { font-weight: 600; font-size: 11px; color: #A9802C; }
  .stars-badge.pop { animation: starPop .5s ease; }
  @keyframes starPop { 0%{transform:scale(1);} 40%{transform:scale(1.16);} 100%{transform:scale(1);} }

  #module-view { flex: 1; overflow-y: auto; padding: 34px 56px 48px; background: var(--page); }
  body.module-mode #slide-container,
  body.module-mode #read-aloud-bar,
  body.module-mode #nav-controls,
  body.module-mode #progress-bar { display: none; }
  #module-view[hidden] { display: none; }

  .module-inner { max-width: 920px; margin: 0 auto; }
  .module-head { max-width: 920px; margin: 0 auto 26px; }
  .module-eyebrow { font-size: 11px; font-weight: 700; letter-spacing: .15em; text-transform: uppercase; }
  .module-title { font-family: 'Playfair Display', serif; font-size: 2rem; font-weight: 900; color: var(--ink); line-height: 1.12; margin-top: 6px; }
  .module-sub { color: var(--ink-soft); font-size: .95rem; margin-top: 9px; line-height: 1.6; max-width: 680px; }
  .module-accent { height: 3px; width: 56px; border-radius: 2px; margin: 14px 0; }

  /* Week switcher */
  .wk-switcher { display: flex; gap: 7px; flex-wrap: wrap; margin-bottom: 18px; }
  .wk-pill {
    border: 1px solid var(--line); background: #fff; color: var(--ink-soft);
    border-radius: 20px; padding: 6px 14px; font-family: 'Inter', sans-serif;
    font-size: 12px; font-weight: 600; cursor: pointer; transition: all .15s;
  }
  .wk-pill:hover { color: var(--ink); border-color: var(--ink-soft); }
  .wk-pill.active { color: #fff; }

  /* Quiz reveal controls + self-assess */
  .quiz-controls { display: flex; align-items: center; gap: 14px; margin-top: 14px; flex-wrap: wrap; }
  .rate { display: flex; align-items: center; gap: 8px; transition: opacity .2s; }
  .rate.hidden-rate { opacity: 0; pointer-events: none; }
  .rate-label { font-size: 12px; color: var(--ink-soft); font-weight: 600; }
  .rate-btn {
    width: 34px; height: 34px; border-radius: 9px; border: 1.5px solid var(--line);
    background: #fff; font-size: 20px; font-weight: 700; line-height: 1; cursor: pointer;
    display: flex; align-items: center; justify-content: center; transition: all .14s; color: var(--ink-soft);
  }
  .rate-btn.minus:hover, .rate-btn.minus.on { background: var(--gold); border-color: var(--gold); color: #fff; }
  .rate-btn.plus:hover, .rate-btn.plus.on { background: var(--green-accent); border-color: var(--green-accent); color: #fff; }

  /* shared buttons */
  .btn { border: none; cursor: pointer; font-family: 'Inter', sans-serif; font-size: 12.5px; font-weight: 600;
    padding: 9px 16px; border-radius: 9px; display: inline-flex; align-items: center; gap: 7px; transition: all .16s; }
  .btn-ghost { background: #fff; border: 1px solid var(--line); color: var(--ink); }
  .btn-ghost:hover { border-color: var(--teal); color: var(--teal); }
  .btn-primary { background: var(--teal); color: #fff; }
  .btn-primary:hover { background: var(--teal-dark); }
  .btn-done { background: var(--green-accent); color: #fff; }
  .btn:disabled { opacity: .5; cursor: default; }

  /* Explore challenges */
  .challenge { background: #fff; border: 1px solid var(--line); border-radius: 14px; padding: 20px 22px; margin-bottom: 14px; box-shadow: 0 1px 2px rgba(17,32,59,.04); transition: border-color .2s; }
  .challenge.done { border-color: rgba(21,163,74,.45); }
  .challenge-top { display: flex; align-items: flex-start; gap: 14px; }
  .challenge-num { width: 36px; height: 36px; border-radius: 10px; flex-shrink: 0; display: flex; align-items: center; justify-content: center; font-weight: 800; color: #fff; font-size: 14px; }
  .challenge.done .challenge-num { background: var(--green-accent) !important; }
  .challenge h4 { font-size: 1.02rem; color: var(--ink); font-weight: 700; line-height: 1.3; }
  .challenge-prompt { color: var(--ink-soft); font-size: .92rem; line-height: 1.62; margin-top: 5px; }
  .challenge-actions { display: flex; gap: 10px; margin-top: 15px; flex-wrap: wrap; padding-left: 50px; }
  .reveal-box { margin: 14px 0 0 50px; padding: 14px 16px; border-radius: 10px; background: rgba(46,95,232,.06); border-left: 3px solid var(--teal); color: var(--ink); font-size: .9rem; line-height: 1.62; display: none; }
  .reveal-box strong { color: var(--teal); }
  .reveal-box.show { display: block; animation: fadeUp .3s ease; }

  /* Quiz */
  .quiz-progress { display: flex; align-items: center; gap: 14px; margin-bottom: 20px; }
  .quiz-bar { flex: 1; height: 8px; border-radius: 5px; background: var(--line); overflow: hidden; }
  .quiz-bar-fill { height: 100%; width: 0; background: linear-gradient(90deg, var(--teal), var(--gold)); transition: width .35s ease; }
  .quiz-score { font-weight: 700; font-size: 13px; color: var(--ink); white-space: nowrap; }
  .q-card { background: #fff; border: 1px solid var(--line); border-radius: 14px; padding: 20px 22px; margin-bottom: 14px; box-shadow: 0 1px 2px rgba(17,32,59,.04); }
  .q-num { font-family: 'JetBrains Mono', monospace; font-size: 11px; font-weight: 600; color: var(--teal); letter-spacing: .05em; }
  .q-text { font-size: 1.05rem; color: var(--ink); font-weight: 600; margin: 6px 0 14px; line-height: 1.4; }
  .q-opts { display: flex; flex-direction: column; gap: 9px; }
  .q-opt { text-align: left; border: 1px solid var(--line); background: var(--page); border-radius: 10px; padding: 12px 14px; cursor: pointer; font-family: 'Inter', sans-serif; font-size: .92rem; font-weight: 500; color: var(--ink); display: flex; align-items: center; gap: 11px; transition: all .15s; }
  .q-opt:hover:not(.disabled) { border-color: var(--teal); background: #fff; }
  .q-opt .opt-key { width: 25px; height: 25px; border-radius: 7px; background: #fff; border: 1px solid var(--line); display: flex; align-items: center; justify-content: center; font-weight: 700; font-size: 12px; flex-shrink: 0; }
  .q-opt.disabled { cursor: default; }
  .q-opt.correct { background: rgba(21,163,74,.10); border-color: var(--green-accent); color: #0B6B30; }
  .q-opt.correct .opt-key { background: var(--green-accent); color: #fff; border-color: var(--green-accent); }
  .q-opt.wrong { background: rgba(214,49,60,.08); border-color: var(--gold); color: #9B1C25; }
  .q-opt.wrong .opt-key { background: var(--gold); color: #fff; border-color: var(--gold); }
  .q-explain { margin-top: 13px; padding: 12px 15px; border-radius: 10px; font-size: .88rem; line-height: 1.55; display: none; }
  .q-explain.show { display: block; animation: fadeUp .3s ease; }
  .q-explain.ok { background: rgba(21,163,74,.08); color: #0B6B30; border-left: 3px solid var(--green-accent); }
  .q-explain.no { background: rgba(214,49,60,.07); color: #9B1C25; border-left: 3px solid var(--gold); }
  .quiz-summary { text-align: center; padding: 26px; background: #fff; border: 1px solid var(--line); border-radius: 16px; margin-top: 6px; box-shadow: 0 1px 2px rgba(17,32,59,.04); }
  .quiz-summary .qs-stars { font-size: 1.6rem; letter-spacing: 4px; color: #F2A413; }
  .quiz-summary h3 { font-family: 'Playfair Display', serif; font-size: 1.5rem; color: var(--ink); margin: 8px 0 4px; }
  .quiz-summary p { color: var(--ink-soft); font-size: .92rem; }

  /* Assignment */
  .assign-intro { background: #fff; border: 1px solid var(--line); border-radius: 14px; padding: 18px 20px; margin-bottom: 16px; color: var(--ink-soft); font-size: .92rem; line-height: 1.62; box-shadow: 0 1px 2px rgba(17,32,59,.04); }
  .assign-intro strong { color: var(--ink); }
  .assign-task { background: #fff; border: 1px solid var(--line); border-radius: 14px; padding: 18px 20px; margin-bottom: 12px; box-shadow: 0 1px 2px rgba(17,32,59,.04); }
  .assign-task-head { display: flex; align-items: flex-start; gap: 13px; }
  .assign-check { width: 25px; height: 25px; border-radius: 7px; border: 2px solid var(--line); flex-shrink: 0; cursor: pointer; display: flex; align-items: center; justify-content: center; color: #fff; font-size: 13px; background: #fff; transition: all .15s; margin-top: 1px; }
  .assign-check.checked { background: var(--green-accent); border-color: var(--green-accent); }
  .assign-task h4 { font-size: 1rem; color: var(--ink); font-weight: 700; line-height: 1.3; }
  .assign-task p { color: var(--ink-soft); font-size: .88rem; line-height: 1.55; margin-top: 4px; }
  .assign-input { width: 100%; margin-top: 12px; border: 1px solid var(--line); border-radius: 10px; padding: 11px 13px; font-family: 'Inter', sans-serif; font-size: .9rem; color: var(--ink); background: var(--page); resize: vertical; min-height: 70px; line-height: 1.55; }
  .assign-input:focus { outline: none; border-color: var(--teal); background: #fff; }
  .assign-submit-row { display: flex; align-items: center; gap: 14px; margin-top: 18px; flex-wrap: wrap; }
  .assign-status { font-size: .85rem; color: var(--ink-soft); }

  @keyframes fadeUp { from { opacity: 0; transform: translateY(8px); } to { opacity: 1; transform: translateY(0); } }

  /* Reward toast */
  #reward-toast {
    position: fixed; bottom: 26px; left: 50%; transform: translateX(-50%) translateY(20px);
    background: var(--ink); color: #fff; padding: 12px 20px; border-radius: 12px;
    font-family: 'Inter', sans-serif; font-size: 13px; font-weight: 600;
    display: flex; align-items: center; gap: 9px; opacity: 0; pointer-events: none;
    transition: opacity .35s, transform .35s; z-index: 200;
    box-shadow: 0 16px 44px -12px rgba(17,32,59,.55);
  }
  #reward-toast.show { opacity: 1; transform: translateX(-50%) translateY(0); }
  #reward-toast .rt-star { color: #FFCB45; font-size: 17px; }

  @media (max-width: 768px) {
    #mode-bar { padding: 8px 12px 8px 58px; flex-wrap: wrap; gap: 8px; }
    .mode-tabs { width: 100%; overflow-x: auto; scrollbar-width: none; }
    .mode-tabs::-webkit-scrollbar { display: none; }
    .mode-tab { padding: 7px 12px; font-size: 12px; }
    .stars-badge { order: -1; }
    #module-view { padding: 22px 16px 40px; }
    .module-title { font-size: 1.5rem; }
    .challenge-actions, .reveal-box { padding-left: 0; margin-left: 0; }
  }