:root {
  --bg: #fbfaf7;
  --surface: #ffffff;
  --ink: #1d1d1f;
  --muted: #6b6b70;
  --accent: #c2410c;
  --rule: #e6e3dc;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  height: 100%;
  overflow: hidden;
  background: var(--bg);
  color: var(--ink);
  font-family: 'Inter', system-ui, sans-serif;
}

/* Stage: fixed 1280x720 canvas, scaled to fit by app.js */
.viewport { position: fixed; inset: 0; }
.stage {
  position: absolute;
  top: 50%;
  left: 50%;
  width: 1280px;
  height: 720px;
  transform-origin: center;
}

.slide {
  width: 100%;
  height: 100%;
  padding: 72px 96px;
  display: flex;
  flex-direction: column;
  justify-content: center;
  font-size: 30px;
  animation: fade-in 0.25s ease-out;
}
@keyframes fade-in { from { opacity: 0; } to { opacity: 1; } }

.slide h1, .slide h2 { font-weight: 700; letter-spacing: -0.02em; line-height: 1.1; margin: 0 0 0.5em; }
.slide h1 { font-size: 2.67em; }
.slide h2 { font-size: 1.73em; }
.slide p { line-height: 1.45; margin: 0 0 0.4em; }
.slide ul, .slide ol { margin: 0; padding-left: 1.1em; line-height: 1.45; }
.slide li + li { margin-top: 0.35em; }

.eyebrow {
  font-size: 16px;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 20px;
}
.lede { font-size: 1.13em; color: var(--muted); }

/* Content slides */
.slide h3 { font-size: 0.8em; font-weight: 600; color: var(--accent); margin: 0 0 0.5em; }
.slide .statement { font-size: 1.6em; max-width: 30ch; }
.slide .cols { display: grid; grid-template-columns: 1fr 1fr; gap: 56px; align-items: start; }
.slide .cols.wide-right { grid-template-columns: 2fr 3fr; }
.slide .cols.wide-left { grid-template-columns: 3fr 2fr; }
.slide .aside { margin-top: 1em; color: var(--muted); }
.slide .subtitle { color: var(--muted); margin: -0.6em 0 1.2em; }
.slide .purpose { color: var(--muted); font-style: italic; font-size: 0.9em; margin: -0.3em 0 0.6em; }
.slide li.headline { font-weight: 600; color: var(--accent); }
.slide .tag { display: inline-block; font-size: 0.6em; font-weight: 700; letter-spacing: 0.08em; text-transform: uppercase; vertical-align: 0.2em; color: #fff; background: var(--accent); border-radius: 4px; padding: 0.1em 0.5em; margin-left: 0.3em; }
.slide .aside strong { color: var(--ink); }
.slide.is-dense { font-size: 22px; }
.slide.is-dense h2 { font-size: 1.9em; }
.timeline { list-style: none; padding: 0 !important; display: grid; gap: 0; }
.timeline li { display: grid; grid-template-columns: 200px 1fr; gap: 32px; padding: 18px 0; border-top: 1px solid var(--rule); margin: 0 !important; }
.timeline li:last-child { border-bottom: 1px solid var(--rule); }
.timeline .when { font-weight: 600; color: var(--accent); }
.muted { color: var(--muted); }

/* Focus mode (Space): the current section stays sharp, the rest blur and fade. */
.slide [data-focus] { transition: filter 0.25s ease, opacity 0.25s ease; }
.slide.focusing [data-focus]:not(.focused) { filter: blur(5px); opacity: 0.35; }

/* Full-bleed slides fill the window instead of the scaled stage; side gutters keep the nav buttons clear. */
.full { position: absolute; inset: 0 72px 4px; display: none; }
.is-full .full { display: block; }
.is-full .stage { display: none; }
.slide.is-prototype { padding: 0; }
.proto-frame { flex: 1; width: 100%; border: 0; background: var(--bg); }
.proto-bar {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 4px 16px;
  padding: 14px 16px 10px;
  border-bottom: 1px solid var(--rule);
  font-size: 16px;
}
.proto-bar .eyebrow { margin: 0; font-size: 13px; }
.proto-title { font-weight: 600; }
.proto-key { margin-left: auto; color: var(--muted); font-size: 14px; }

/* Previous / next: large buttons on the left and right edges */
.nav-btn {
  position: fixed;
  top: 50%;
  width: 52px;
  height: 52px;
  margin-top: -26px;
  border: 1px solid var(--rule);
  border-radius: 50%;
  background: var(--surface);
  box-shadow: 0 4px 16px rgb(0 0 0 / 0.08);
  cursor: pointer;
  z-index: 5;
}
.nav-btn.prev { left: 10px; }
.nav-btn.next { right: 10px; }
/* Chevron drawn with borders */
.nav-btn::before {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  width: 12px;
  height: 12px;
  border-right: 3px solid var(--accent);
  border-bottom: 3px solid var(--accent);
}
.nav-btn.next::before { transform: translate(-70%, -50%) rotate(-45deg); }
.nav-btn.prev::before { transform: translate(-30%, -50%) rotate(135deg); }
.nav-btn:hover:not(:disabled) { background: var(--rule); }
.nav-btn:disabled { opacity: 0.3; cursor: default; }

.hud {
  position: fixed;
  right: 16px;
  bottom: 12px;
  font-size: 13px;
  color: var(--muted);
  font-variant-numeric: tabular-nums;
}
.is-full .hud { display: none; }

.progress { position: fixed; left: 0; right: 0; bottom: 0; height: 3px; background: var(--rule); }
.progress-bar { height: 100%; background: var(--accent); transition: width 0.25s ease; }

/* Phones: no side gutters for full-bleed slides; smaller nav buttons over the content. */
@media (max-width: 700px) {
  .full { inset: 0 0 4px; }
  .nav-btn { width: 40px; height: 40px; margin-top: -20px; opacity: 0.9; }
  .nav-btn.prev { left: 4px; }
  .nav-btn.next { right: 4px; }
}