:root {
  color-scheme: light;
  --bg: #f5f5f7;
  --surface: #fff;
  --text: #1d1d1f;
  --muted: #6e6e73;
  --line: rgba(0,0,0,.08);
  --accent: #0a84ff;
  --danger: #ff3b30;
  --dock: rgba(249,249,249,.78);
  --dock-ink: #1d1d1f;
  --pill: rgba(0,0,0,.08);
}
@media (prefers-color-scheme: dark) {
  :root {
    color-scheme: dark;
    --bg: #000;
    --surface: #1d1d1f;
    --text: #f5f5f7;
    --muted: #86868b;
    --line: rgba(255,255,255,.12);
    --accent: #0a84ff;
    --danger: #ff453a;
    --dock: rgba(18,18,20,.68);
    --dock-ink: #fff;
    --pill: rgba(255,255,255,.18);
  }
}
* { box-sizing: border-box; }
html, body { margin: 0; background: var(--bg); color: var(--text); font: 17px/1.45 -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif; }
body { min-height: 100dvh; }
a { color: var(--accent); }
.top {
  position: relative;
  display: flex;
  align-items: center;
  gap: 12px;
  padding: calc(16px + env(safe-area-inset-top, 0px)) 16px 12px;
}
.brand { color: var(--text); font-weight: 650; text-decoration: none; }
.top-links { margin-left: auto; display: flex; gap: 12px; }
.top-links a { color: var(--text); text-decoration: none; font-size: 15px; }
.back {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  flex: 0 0 36px;
  background: var(--surface);
  color: var(--text);
  text-decoration: none;
  font-size: 0;
  box-shadow: 0 1px 2px rgba(0,0,0,.08);
}
.back::before {
  content: "";
  width: 8px;
  height: 8px;
  border-left: 2px solid currentColor;
  border-bottom: 2px solid currentColor;
  transform: rotate(45deg);
  margin-left: 3px;
}
main { padding: 0 16px calc(96px + env(safe-area-inset-bottom, 0px)); }
h1 { font-size: 28px; margin: 8px 0 12px; }
.lead, .meta { color: var(--muted); }
.search, form { display: grid; gap: 8px; margin: 12px 0 20px; }
input, select, textarea, button {
  font-size: 16px;
  border-radius: 12px;
  border: 1px solid var(--line);
  background: var(--surface);
  color: var(--text);
  padding: 12px 14px;
}
textarea { min-height: 96px; }
button { background: var(--accent); color: #fff; border: 0; }
.card, blockquote {
  background: var(--surface);
  border-radius: 16px;
  padding: 16px;
  margin: 0 0 12px;
}
.card h2 { margin: 0 0 6px; font-size: 20px; }
.card h2 a { color: var(--text); text-decoration: none; }
.flags { padding-left: 18px; color: var(--muted); }
.score { font-weight: 650; }
.error { color: var(--danger); }
.examples, .rubrics { padding-left: 18px; }
.compare { display: grid; gap: 12px; }
@media (min-width: 900px) {
  .compare { grid-template-columns: 1fr 1fr 1fr; }
  main { max-width: 980px; margin: 0 auto; }
}
.insta-tabs {
  position: fixed;
  left: 48px;
  right: 48px;
  bottom: calc(12px + env(safe-area-inset-bottom, 0px));
  z-index: 60;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  height: 56px;
  padding: 5px;
  background: var(--dock);
  border: 1px solid var(--line);
  border-radius: 28px;
  box-shadow: 0 14px 36px rgba(0,0,0,.18);
  backdrop-filter: blur(20px) saturate(120%);
  -webkit-backdrop-filter: blur(20px) saturate(120%);
}
.insta-tabs a {
  position: relative;
  z-index: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 46px;
  border-radius: 23px;
  color: var(--dock-ink);
  text-decoration: none;
}
.insta-tabs svg { width: 24px; height: 24px; }
.insta-tabs a.nav-icon-run svg { animation: nav-bob 640ms ease; }
@keyframes nav-bob {
  0% { transform: translateY(0); }
  40% { transform: translateY(-4px); }
  100% { transform: translateY(0); }
}
.insta-tabs .label { display: none; }
.dock-pill {
  position: absolute;
  top: 5px;
  height: 46px;
  border-radius: 23px;
  background: var(--pill);
  transition: left .45s ease, width .45s ease;
}
pre {
  white-space: pre-wrap;
  background: var(--surface);
  padding: 12px;
  border-radius: 12px;
  overflow-wrap: anywhere;
}
.check { display: flex; gap: 8px; align-items: center; }
@media (max-width: 350px) {
  .insta-tabs { left: 16px; right: 16px; }
}