:root {
  --bg: #000;
  --cyan: #00e5e5;
  --cyan-soft: #93ffff;
  --text: #f6f7fb;
  --muted: #b9c1ca;
  --dim: #78828c;
  --line: rgba(255,255,255,0.16);
  --panel: rgba(255,255,255,0.045);
  --font-display: "General Sans", ui-sans-serif, system-ui, sans-serif;
  --font-body: "Satoshi", ui-sans-serif, system-ui, sans-serif;
}

* { box-sizing: border-box; }
html { background: var(--bg); scroll-behavior: smooth; }
body {
  margin: 0;
  background:
    radial-gradient(circle at 88% 12%, rgba(0,229,229,0.12), transparent 34rem),
    radial-gradient(circle at 8% 48%, rgba(0,229,229,0.08), transparent 42rem),
    var(--bg);
  color: var(--text);
  font-family: var(--font-body);
}
a { color: inherit; }

.slide-page {
  min-height: auto;
  display: block;
  padding: clamp(1rem, 3vw, 2rem);
  scroll-margin-top: 0;
}

.slide-art {
  width: 100%;
  margin: 0;
  background: #000;
  border: 1px solid rgba(255,255,255,0.12);
  position: relative;
  border-radius: clamp(16px, 2vw, 28px);
  overflow: hidden;
}
.slide-art img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 9;
  object-fit: contain;
  background: #000;
}

.toc-slide {
  width: min(100%, 1400px);
  aspect-ratio: 16 / 9;
  background:
    radial-gradient(circle at 82% 18%, rgba(0,229,229,0.16), transparent 24rem),
    #030406;
  border: 1px solid var(--line);
  padding: clamp(1rem, 3.6vw, 3rem);
  display: grid;
  grid-template-columns: minmax(8rem, 0.35fr) minmax(0, 1fr);
  grid-template-rows: auto auto 1fr auto;
  gap: clamp(0.6rem, 1.4vw, 1.2rem) clamp(1rem, 3vw, 3rem);
  overflow: hidden;
}
.toc-brand {
  grid-row: 1 / span 2;
  color: var(--text);
  font-family: var(--font-display);
  font-size: clamp(0.7rem, 1.3vw, 1.1rem);
  font-weight: 700;
  line-height: 0.95;
  letter-spacing: -0.02em;
}
.toc-kicker {
  margin: 0;
  color: var(--cyan);
  font-family: var(--font-display);
  font-size: clamp(0.65rem, 1vw, 0.9rem);
  font-weight: 700;
  letter-spacing: 0.16em;
  text-transform: uppercase;
}
.toc-slide h1 {
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(2rem, 5vw, 5rem);
  line-height: 0.95;
  letter-spacing: -0.055em;
}
.toc-list {
  grid-column: 2;
  display: grid;
  gap: clamp(0.35rem, 0.9vw, 0.8rem);
  align-content: start;
}
.toc-item {
  display: grid;
  grid-template-columns: 2.1rem minmax(0, 1fr);
  gap: 0.8rem;
  align-items: start;
  padding: clamp(0.3rem, 0.8vw, 0.58rem) 0;
  border-bottom: 1px solid rgba(255,255,255,0.12);
  text-decoration: none;
}
.toc-item:hover .toc-title,
.toc-item:focus-visible .toc-title {
  color: var(--cyan);
}
.toc-num {
  color: var(--cyan);
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(0.68rem, 1.1vw, 0.95rem);
}
.toc-title {
  display: block;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(0.78rem, 1.35vw, 1.12rem);
  line-height: 1.1;
}
.toc-detail {
  display: block;
  margin-top: 0.15rem;
  color: var(--muted);
  font-size: clamp(0.58rem, 0.92vw, 0.78rem);
  line-height: 1.25;
}
.toc-footer {
  grid-column: 1 / -1;
  align-self: end;
  margin: 0;
  color: rgba(255,255,255,0.5);
  font-size: clamp(0.58rem, 0.85vw, 0.75rem);
  font-weight: 700;
}

.slides {
  width: 100%;
}
.section-slides {
  width: min(100%, 1400px);
  margin: 0 auto;
  padding: clamp(2rem, 4vw, 3rem) 0;
  display: grid;
  gap: clamp(1.5rem, 3vw, 2.5rem);
  scroll-margin-top: 0;
  border-top: 1px solid rgba(255,255,255,0.12);
}
.section-header {
  position: sticky;
  top: 0;
  z-index: 20;
  width: 100%;
  justify-self: stretch;
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 1rem;
  align-items: center;
  padding: 1rem 0;
  background: linear-gradient(180deg, rgba(0,0,0,0.96), rgba(0,0,0,0.72));
  backdrop-filter: blur(14px);
}
.section-kicker {
  display: none;
}
.section-title {
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(1.65rem, 4vw, 4rem);
  line-height: 0.95;
  letter-spacing: -0.055em;
}
.section-detail {
  max-width: 68rem;
  margin: 0.45rem 0 0;
  color: var(--muted);
  font-size: clamp(0.9rem, 1.4vw, 1.08rem);
  line-height: 1.35;
}
.section-detail-links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin: 0.85rem 0 0;
  color: var(--muted);
  font-size: clamp(0.84rem, 1.2vw, 1rem);
}
.section-detail-links a {
  color: inherit;
  text-decoration: none;
  border-bottom: 1px solid transparent;
  padding-bottom: 1px;
}
.section-detail-links a:hover,
.section-detail-links a:focus-visible {
  border-bottom-color: var(--cyan);
}
.exit-link {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 2.6rem;
  padding: 0.65rem 0.95rem;
  border: 1px solid rgba(255,255,255,0.2);
  border-radius: 999px;
  color: var(--text);
  background: rgba(0,0,0,0.7);
  font-family: var(--font-display);
  font-weight: 700;
  text-decoration: none;
}
.exit-link:hover,
.exit-link:focus-visible {
  color: #001214;
  background: var(--cyan);
  border-color: var(--cyan);
}
.section-slide {
  width: 100%;
  justify-self: stretch;
  padding: 0;
  opacity: 1;
  transform: translateY(0);
  transition: opacity 700ms ease, transform 700ms ease;
}
.section-slide.reveal-hidden {
  opacity: 0;
  transform: translateY(30px);
}
.section-slide.reveal-visible {
  opacity: 1;
  transform: translateY(0);
}
.section-slide .slide-art {
  width: 100%;
  border-radius: 0;
  overflow: visible;
  box-shadow: none;
  will-change: transform, opacity;
}
.video-overlay {
  position: absolute;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  gap: 0.35rem;
  padding: clamp(0.35rem, 1.2vw, 0.85rem);
  border: 1px solid rgba(0,229,229,0.72);
  border-radius: clamp(9px, 1.4vw, 18px);
  color: var(--cyan-soft);
  background: rgba(0,0,0,0.7);
  box-shadow:
    0 0 0 1px rgba(255,255,255,0.08) inset,
    0 18px 40px rgba(0,0,0,0.42);
  backdrop-filter: blur(6px);
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(0.64rem, 1.25vw, 1rem);
  line-height: 1.15;
  text-decoration: none;
  overflow: hidden;
}
.video-overlay::before {
  content: "▶";
  width: 1.55em;
  height: 1.55em;
  display: inline-grid;
  place-items: center;
  flex: 0 0 auto;
  border-radius: 999px;
  color: #001214;
  background: var(--cyan);
  font-size: 0.82em;
}
.video-overlay:hover,
.video-overlay:focus-visible {
  color: #001214;
  background: var(--cyan);
  border-color: var(--cyan);
}
.video-overlay:hover::before,
.video-overlay:focus-visible::before {
  color: var(--cyan);
  background: #001214;
}
.video-overlay.is-small {
  min-width: 9rem;
  min-height: 2.6rem;
  transform: translateY(-100%);
}

@media (max-width: 760px) {
  html { scroll-behavior: auto; }
  .slide-page {
    min-height: auto;
    padding: 0;
  }
  .toc-page {
    min-height: 100svh;
    padding: 0.65rem;
  }
  .toc-slide {
    min-height: calc(100svh - 1.3rem);
    aspect-ratio: auto;
    grid-template-columns: 1fr;
    grid-template-rows: auto auto auto 1fr auto;
    padding: 1rem;
  }
  .toc-brand {
    grid-row: auto;
  }
  .toc-list {
    grid-column: 1;
  }
  .toc-item {
    grid-template-columns: 1.6rem minmax(0, 1fr);
  }
  .section-slides {
    padding: 0.75rem 0.5rem 1.75rem;
  }
  .section-header {
    grid-template-columns: 1fr;
    padding: 0.75rem 0;
  }
  .exit-link {
    justify-self: start;
  }
  .section-slide .slide-art {
    border-radius: 10px;
  }
  .video-overlay {
    font-size: 0.7rem;
    border-radius: 10px;
  }
  .video-overlay.is-small {
    min-width: 7.5rem;
    min-height: 2.2rem;
  }
}

.login-screen {
  position: fixed;
  inset: 0;
  display: grid;
  place-items: center;
  padding: 1.25rem;
  background: radial-gradient(circle at top left, rgba(0,229,229,0.18), transparent 32%),
    radial-gradient(circle at 90% 20%, rgba(0,229,229,0.1), transparent 26%),
    rgba(0,0,0,0.95);
  z-index: 9999;
}

.login-card {
  width: min(100%, 420px);
  padding: clamp(1.5rem, 2.5vw, 2.5rem);
  background: rgba(255,255,255,0.05);
  border: 1px solid rgba(255,255,255,0.14);
  border-radius: 28px;
  backdrop-filter: blur(18px);
  box-shadow: 0 30px 80px rgba(0, 0, 0, 0.45);
}

.login-brand {
  margin: 0 0 0.8rem;
  color: var(--cyan);
  font-family: var(--font-display);
  font-size: clamp(0.8rem, 1.2vw, 1rem);
  font-weight: 700;
  letter-spacing: 0.2em;
  text-transform: uppercase;
}

.login-card h1 {
  margin: 0 0 0.75rem;
  font-family: var(--font-display);
  font-size: clamp(2rem, 4vw, 2.8rem);
  line-height: 1.05;
}

.login-card p {
  margin: 0 0 1.6rem;
  color: var(--muted);
  font-size: 0.96rem;
  line-height: 1.6;
}

.login-form {
  display: grid;
  gap: 1rem;
}

.login-label {
  color: var(--text);
  font-size: 0.9rem;
  font-weight: 600;
}

.login-input {
  width: 100%;
  min-height: 3rem;
  padding: 0.95rem 1rem;
  border: 1px solid rgba(255,255,255,0.16);
  border-radius: 14px;
  background: rgba(255,255,255,0.06);
  color: var(--text);
  font-size: 1rem;
}

.login-input:focus {
  outline: 2px solid rgba(0,229,229,0.55);
  outline-offset: 2px;
}

.login-button {
  min-height: 3rem;
  border: none;
  border-radius: 14px;
  color: #001214;
  background: var(--cyan);
  font-family: var(--font-display);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  cursor: pointer;
}

.login-button:hover,
.login-button:focus-visible {
  background: #74f7f7;
}

.login-error {
  margin: 0;
  color: #ff8787;
  min-height: 1.2rem;
  font-size: 0.95rem;
}