@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700;800&family=JetBrains+Mono:wght@400;500;600&display=swap');

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

  html {
    font-size: 30px;
    width: 100%;
    height: 100%;
  }

  :root {
    --deck-nav-height: 1.8rem;
    --deck-takeaway-gap: 0;
    --deck-takeaway-body-gap: 0.18rem;
    --bg: #f8f9ff;
    --surface: #edf0f8;
    --surface2: #e2e6f2;
    --border: #9aa0be;
    --text: #0d1020;
    --text-dim: #3d4570;
    --accent: #2a4fd6;
    --accent-glow: rgba(42,79,214,0.18);
    --green: #0f6e2f;
    --green-glow: rgba(15,110,47,0.15);
    --red: #c01c1c;
    --orange: #a05000;
    --purple: #5a30c8;
    --yellow: #6a4f00;
    --cyan: #007890;
    --pink: #980f60;
    --arch-arrow-length: 1.2rem;
    --arch-arrow-length-detail: 0.95rem;
  }

  body {
    background: var(--bg);
    color: var(--text);
    font-family: 'Inter', sans-serif;
    width: 100%;
    height: 100%;
    overflow: hidden;
  }

  #deckViewport {
    position: fixed;
    inset: 0;
    overflow: hidden;
  }

  #deckRoot {
    position: absolute;
    left: 50%;
    top: 50%;
    width: 1920px;
    height: 1080px;
    transform-origin: center center;
  }

  .slide-container {
    position: absolute;
    inset: 0 0 var(--deck-nav-height) 0;
    overflow: hidden;
  }

  .slide {
    position: absolute;
    inset: 0;
    display: none;
    flex-direction: column;
    padding: 1.2rem 2.35rem 1rem;
    overflow: hidden;
    animation: fadeSlideIn 0.4s cubic-bezier(0.25, 0.46, 0.45, 0.94);
  }

  .slide.active { display: flex; }

  .slide.centered {
    justify-content: center;
    align-items: center;
    text-align: center;
  }

  /* ── Slide Region System ── */
  .slide-header {
    flex: 0 0 auto;
    padding-top: 0.55rem;
  }

  .slide-body {
    flex: 1 1 auto;
    min-height: 0;
    display: flex;
    flex-direction: column;
  }

  .slide-body > .story-layout,
  .slide-body > .attn19-layout,
  .slide-body > .grid-2,
  .slide-body > .grid-3,
  .slide-body > .block28-layout,
  .slide-body > .stack31-layout,
  .slide-body > .pred32-layout,
  .slide-body > .close33-layout,
  .slide-body > .card {
    flex: 1 1 auto;
    min-height: 0;
  }

  .slide-body > .callout,
  .slide-body > .template-note,
  .slide-body > .story-takeaway {
    flex: 0 0 auto;
  }

  .slide.slide-has-takeaway {
    padding-bottom: 0;
  }

  .slide.slide-has-takeaway .slide-body {
    gap: var(--deck-takeaway-body-gap);
  }

  .slide.slide-has-takeaway > .attn18-layout,
  .slide.slide-has-takeaway > .attn19-layout,
  .slide.slide-has-takeaway > .attn21-layout,
  .slide.slide-has-takeaway > .card,
  .slide.slide-has-takeaway .slide-body > .attn19-layout,
  .slide.slide-has-takeaway .slide-body > .story-layout,
  .slide.slide-has-takeaway .slide-body > .block28-layout,
  .slide.slide-has-takeaway .slide-body > .stack31-layout,
  .slide.slide-has-takeaway .slide-body > .pred32-layout,
  .slide.slide-has-takeaway .slide-body > .close33-layout,
  .slide.slide-has-takeaway .slide-body > .card {
    flex: 1 1 auto;
    min-height: 0;
  }

  .slide.slide-has-takeaway > .attn18-takeaway,
  .slide.slide-has-takeaway > .attn19p1-takeaway,
  .slide.slide-has-takeaway > .attn19-takeaway,
  .slide.slide-has-takeaway > .attn21-takeaway,
  .slide.slide-has-takeaway .attn19-takeaway,
  .slide.slide-has-takeaway .story-takeaway,
  .slide.slide-has-takeaway .block28-takeaway {
    margin-top: auto;
    margin-bottom: var(--deck-takeaway-gap);
    padding: 0.38rem 0.62rem;
    line-height: 1.35;
  }

  @keyframes fadeSlideIn {
    from { opacity: 0; transform: translateY(1rem); }
    to   { opacity: 1; transform: translateY(0); }
  }

  h1 {
    font-size: var(--fs-2xl);
    font-weight: 800;
    letter-spacing: -0.03em;
    line-height: 1.12;
    background: linear-gradient(135deg, var(--accent) 0%, var(--purple) 60%, var(--pink) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
  }

  h1.large { font-size: 3.5rem; }

  h2 {
    font-size: var(--fs-xl);
    font-weight: 700;
    letter-spacing: -0.02em;
    margin-bottom: var(--sp-2);
  }

  h3 {
    font-size: var(--fs-lg);
    font-weight: 600;
    margin-bottom: var(--sp-2);
  }

  .subtitle {
    font-size: var(--fs-lg);
    color: var(--text-dim);
    margin-top: var(--sp-2);
    line-height: 1.5;
  }

  .small-text {
    font-size: var(--fs-sm);
    color: var(--text-dim);
    line-height: 1.45;
  }

  .tiny {
    font-size: var(--fs-xs);
    color: var(--text-dim);
  }

  .spacer    { height: var(--sp-4); }
  .spacer-sm { height: var(--sp-3); }
  .spacer-lg { height: var(--sp-5); }

  .gradient-line {
    width: 12.5rem;
    height: 0.125rem;
    border-radius: var(--radius-full);
    background: linear-gradient(90deg, transparent, var(--accent), var(--purple), transparent);
  }

  .section-tag {
    position: absolute;
    top: 0.5rem;
    right: 0.7rem;
    left: auto;
    font-size: 0.66rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.07em;
    color: var(--text-dim);
    opacity: 1;
  }

  .badge {
    display: inline-block;
    position: absolute;
    top: 0.48rem;
    left: 0.68rem;
    z-index: 2;
    font-size: 0.7rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    padding: 0.22rem 0.62rem;
    border-radius: var(--radius-full);
    margin-bottom: 0;
  }

  .slide:not(.centered) > h2,
  .slide:not(.centered) > h1,
  .slide:not(.centered) > .subtitle,
  .slide:not(.centered) > .small-text,
  .slide:not(.centered) > .tiny,
  .slide:not(.centered) > .spacer,
  .slide:not(.centered) > .spacer-sm,
  .slide:not(.centered) > .spacer-lg,
  .slide:not(.centered) > .gradient-line,
  .slide:not(.centered) > .grid-2,
  .slide:not(.centered) > .grid-3,
  .slide:not(.centered) > .card,
  .slide:not(.centered) > .attn18-layout,
  .slide:not(.centered) > .attn19-layout,
  .slide:not(.centered) > .attn21-layout {
    margin-top: 0.95rem;
  }

  .badge.day1     { background: var(--accent-bg); color: var(--accent); }
  .badge.day2     { background: var(--accent-bg); color: var(--accent); }
  .badge.activity { background: var(--green-bg);  color: var(--green); }
  .badge.concept  { background: var(--purple-bg); color: var(--purple); }
  .badge.discussion { background: var(--orange-bg); color: var(--orange); }

  .hl        { color: var(--accent); font-weight: 600; }
  .hl-green  { color: var(--green);  font-weight: 600; }
  .hl-red    { color: var(--red);    font-weight: 600; }
  .hl-orange { color: var(--orange); font-weight: 600; }
  .hl-purple { color: var(--purple); font-weight: 600; }
  .hl-cyan   { color: var(--cyan);   font-weight: 600; }

  /* ── Utility classes ── */
  .mt-1 { margin-top: var(--sp-1); }
  .mt-2 { margin-top: var(--sp-2); }
  .mt-3 { margin-top: var(--sp-3); }
  .mt-4 { margin-top: var(--sp-4); }
  .mb-2 { margin-bottom: var(--sp-2); }
  .mb-3 { margin-bottom: var(--sp-3); }
  .gap-1 { gap: var(--sp-1); }
  .gap-2 { gap: var(--sp-2); }
  .gap-3 { gap: var(--sp-3); }
  .gap-4 { gap: var(--sp-4); }
  .text-base { font-size: var(--fs-base); }
  .text-sm   { font-size: var(--fs-sm); }
  .text-xs   { font-size: var(--fs-xs); }
  .mono { font-family: 'JetBrains Mono', monospace; }