/* Static slide deck shell */
:root {
  --bg: #5c5c5c;
  --bg-pattern: #4f4f4f;
  --ink: #f2f2f2;
  --muted: #c8c8c8;
  --slide-shadow: 0 2px 10px rgb(0 0 0 / 0.35);
  --gutter: clamp(0.75rem, 2vw, 1.5rem);
  --max: min(100%, 1120px);
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-height: 100dvh;
  font-family: "Iowan Old Style", "Palatino Linotype", Palatino, "Book Antiqua", Georgia, serif;
  color: var(--ink);
  background-color: var(--bg);
  background-image:
    linear-gradient(rgb(0 0 0 / 0.12), rgb(0 0 0 / 0.12)),
    repeating-linear-gradient(
      -45deg,
      var(--bg) 0 6px,
      var(--bg-pattern) 6px 7px
    );
}

.topbar {
  position: sticky;
  top: 0;
  z-index: 2;
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.75rem var(--gutter);
  background: rgb(32 32 32 / 0.88);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid rgb(255 255 255 / 0.08);
}

.topbar h1 {
  margin: 0;
  font-size: clamp(0.95rem, 1.6vw, 1.15rem);
  font-weight: 600;
  letter-spacing: 0.01em;
}

.counter {
  margin: 0;
  font-family: ui-monospace, "Cascadia Code", "SF Mono", Menlo, monospace;
  font-size: 0.85rem;
  color: var(--muted);
  white-space: nowrap;
}

.deck {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--gutter);
  padding: var(--gutter);
  padding-bottom: calc(var(--gutter) * 3);
}

.slide-frame {
  width: var(--max);
  aspect-ratio: 2880 / 1620;
  /* Skip off-screen layout work; keep scroll height stable (~1120×630) */
  content-visibility: auto;
  contain-intrinsic-size: auto 630px;
  box-shadow: var(--slide-shadow);
  background: #fff;
}

.slide-frame:first-child {
  /* Keep first slide eagerly laid out for LCP */
  content-visibility: visible;
}

.slide {
  display: block;
  width: 100%;
  height: 100%;
  border: 0;
  background: #fff;
}