html { background: var(--color-paper); color-scheme: light; }
body {
  min-width: 320px;
  min-height: 100vh;
  background: var(--color-paper);
  color: var(--color-ink);
  font-family: var(--font-body);
  font-size: var(--text-body);
  -webkit-font-smoothing: antialiased;
}
a:focus-visible { outline: 3px solid #2455e6; outline-offset: 4px; }
h1 { font-family: var(--font-display); font-size: var(--text-title); font-weight: 400; letter-spacing: -0.04em; line-height: 1.2; }
.visually-hidden { position: absolute !important; width: 1px !important; height: 1px !important; padding: 0 !important; margin: -1px !important; overflow: hidden !important; clip: rect(0, 0, 0, 0) !important; white-space: nowrap !important; border: 0 !important; }

[data-scroll-header] {
  position: sticky;
  top: 0;
  z-index: 80;
  background: var(--color-paper);
  transition: transform 180ms cubic-bezier(.22, 1, .36, 1);
  will-change: transform;
}
[data-scroll-header].is-scroll-hidden { transform: translateY(calc(-100% - 1px)); }

body.is-scroll-header-visible .case-study-jump,
body.is-scroll-header-visible .learning-logs-tree { top: calc(var(--scroll-header-height, 0px) + 1rem); }

@view-transition { navigation: auto; }
::view-transition-old(root) { animation: page-leave 120ms ease-in both; }
::view-transition-new(root) { animation: page-enter 180ms cubic-bezier(.22, 1, .36, 1) both; }
@keyframes page-leave { to { opacity: 0; transform: translateY(-2px); } }
@keyframes page-enter { from { opacity: 0; transform: translateY(3px); } }

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto !important; transition-duration: 0.01ms !important; }
  ::view-transition-old(root),
  ::view-transition-new(root) { animation: none; }
}