/* The guides (made by scripts/guides.py): the front page's colors and
   type, set for reading, dark or light as /appearance.js says. */
:root {
  --bg: #121a24;
  --fg: #d6dde6;
  --surface: #18222f;
  --muted: #5b6b7f;
  --highlight: #f0c35b;
  --accent: #62c7d5;
  --soft: color-mix(in srgb, var(--fg) 72%, var(--bg));
  --rule: color-mix(in srgb, var(--fg) 16%, var(--bg));
  --sans: "IBM Plex Sans", system-ui, sans-serif;
  --display: "Space Grotesk", system-ui, sans-serif;
  --mono: "JetBrains Mono", ui-monospace, monospace;
  --gutter: clamp(16px, 4vw, 48px);
  --button-bg: var(--fg);
  --button-fg: var(--bg);
  --button-hover: var(--accent);
  --shadow: rgb(0 0 0 / 0.4);
  color-scheme: dark;
}

:root[data-theme="light"] {
  --bg: #f5f5f7;
  --fg: #1d1d1f;
  --surface: #ffffff;
  --muted: #6e6e73;
  --highlight: #c45c00;
  --accent: #0066cc;
  --rule: #d2d2d7;
  --button-bg: #0071e3;
  --button-fg: #ffffff;
  --button-hover: #0077ed;
  --shadow: rgb(0 0 0 / 0.12);
  color-scheme: light;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font: 400 1.0625rem/1.65 var(--sans);
  -webkit-font-smoothing: antialiased;
}

a { color: var(--accent); text-underline-offset: 0.2em; }
a:hover { color: var(--fg); }
:focus-visible { outline: 2px solid var(--highlight); outline-offset: 3px; }

code, kbd { font-family: var(--mono); font-size: 0.86em; }
code { color: var(--fg); }
kbd {
  display: inline-block;
  padding: 0 0.35em;
  border: 1px solid var(--rule);
  border-bottom-width: 2px;
  border-radius: 4px;
  line-height: 1.5;
}

.bar {
  position: sticky; top: 0; z-index: 2;
  display: flex; align-items: center; justify-content: space-between; gap: 16px;
  padding: 12px var(--gutter);
  background: color-mix(in srgb, var(--bg) 92%, transparent);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--rule);
}
.brand { display: flex; align-items: center; gap: 10px; text-decoration: none; }
.brand img { display: block; width: 28px; height: 28px; border-radius: 7px; }
.mark {
  font: 700 0.95rem var(--mono);
  color: var(--bg);
  background: var(--highlight);
  padding: 2px 8px;
  border-radius: 3px;
}
.bar nav { display: flex; align-items: center; gap: clamp(12px, 3vw, 28px); }
.bar nav a { color: var(--soft); text-decoration: none; font-size: 0.95rem; }
.bar nav a:hover { color: var(--fg); }
.bar .try {
  color: var(--fg);
  font-weight: 700;
  border: 1px solid var(--soft);
  border-radius: 6px;
  padding: 6px 12px;
}

/* The appearance button (/appearance.js): a sun on a dark page, a moon
   on a light one, the look it switches to. Without the script it does
   nothing, so it is not shown. */
:root:not([data-theme]) .look-button { display: none; }
.bar .look-button {
  display: grid; place-items: center;
  width: 32px; height: 32px;
  padding: 0;
  color: var(--soft);
  background: none;
  border: 0;
  border-radius: 6px;
  cursor: pointer;
}
.bar .look-button:hover { color: var(--fg); background: var(--rule); }
.look-icon {
  display: none;
  width: 18px; height: 18px;
  fill: none;
  stroke: currentColor;
  stroke-width: 1.7;
  stroke-linecap: round;
  stroke-linejoin: round;
}
[data-theme="dark"] .look-light,
[data-theme="light"] .look-dark { display: block; }

main {
  max-width: 44rem;
  margin: 0 auto;
  padding: clamp(32px, 6vw, 64px) 16px 48px;
}

.crumb { margin: 0 0 8px; font: 600 0.8rem var(--mono); letter-spacing: 0.06em; text-transform: uppercase; }
.crumb a { color: var(--highlight); text-decoration: none; }

h1 {
  margin: 0;
  font: 700 clamp(2rem, 5vw, 2.8rem)/1.1 var(--display);
  letter-spacing: -0.02em;
}
h2 { margin: 2.4rem 0 0.6rem; font: 700 1.3rem/1.3 var(--display); }
.guide p, .guide li { color: var(--soft); }
.guide strong, .guide em { color: var(--fg); }
.lede { margin: 18px 0 0; font-size: 1.2rem; color: var(--fg) !important; }
.guide ul { padding-left: 1.2em; }
.guide li + li { margin-top: 8px; }

.formula {
  margin: 18px 0;
  padding: 14px 18px;
  background: var(--surface);
  border-left: 3px solid var(--highlight);
  border-radius: 0 6px 6px 0;
  font: 400 0.98rem/1.5 var(--mono);
  color: var(--fg) !important;
  overflow-x: auto;
}

.try-it {
  margin-top: 48px;
  padding: 24px;
  background: var(--surface);
  border: 1px solid var(--rule);
  border-radius: 8px;
}
.try-it h2 { margin-top: 0; }
.try-it p { margin: 10px 0 0; color: var(--soft); }
.ask { font-family: var(--mono); font-size: 0.92rem; color: var(--fg) !important; }
.button {
  display: inline-block;
  margin-top: 8px;
  padding: 10px 18px;
  border-radius: 6px;
  background: var(--button-bg);
  color: var(--button-fg);
  font-weight: 700;
  text-decoration: none;
}
.button:hover { background: var(--button-hover); color: var(--button-fg); }

.related ul, .guide ul.index { list-style: none; padding: 0; margin: 12px 0 0; }
.related li { padding: 12px 0; border-top: 1px solid var(--rule); }
.related li a { font-weight: 700; }
.related li span { display: block; color: var(--soft); font-size: 0.95rem; }

.guide ul.index { margin-top: 32px; }
.index li + li { margin-top: 0; }
.index a {
  display: block;
  padding: 18px 0;
  border-top: 1px solid var(--rule);
  text-decoration: none;
}
.index li:last-child a { border-bottom: 1px solid var(--rule); }
.index strong { display: block; color: var(--fg); font-size: 1.2rem; }
.index span { color: var(--soft); }
.index a:hover strong { color: var(--accent); }

.foot {
  max-width: 44rem;
  margin: 0 auto;
  padding: 24px 16px 48px;
  border-top: 1px solid var(--rule);
  color: var(--muted);
  font-size: 0.9rem;
}
.foot p { margin: 0 0 8px; }

@media (max-width: 560px) {
  .bar nav a:not(.try) { display: none; }
}