:root {
  --bg: #fbfbfa;
  --surface: #ffffff;
  --text: #1c1f23;
  --muted: #5b6470;
  --border: #e3e5e8;
  --accent: #1f5fbf;
  --accent-soft: #eaf1fb;
  --code-bg: #f3f4f6;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #111418;
    --surface: #181c21;
    --text: #e6e8eb;
    --muted: #9aa3ae;
    --border: #2a3038;
    --accent: #6ea8ff;
    --accent-soft: #1a2638;
    --code-bg: #1f242b;
  }
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: "Inter", system-ui, -apple-system, "Segoe UI", sans-serif;
  font-size: 17px;
  line-height: 1.65;
}
.wrap { max-width: 760px; margin: 0 auto; padding: 48px 20px 80px; }
a { color: var(--accent); text-decoration-thickness: 1px; text-underline-offset: 3px; }
a:hover { text-decoration-thickness: 2px; }
h1, h2, h3 { line-height: 1.25; letter-spacing: -0.01em; }
h1 { font-size: 2.1rem; margin: 0 0 8px; }
h2 { font-size: 1.4rem; margin: 48px 0 12px; }
h3 { font-size: 1.1rem; margin: 28px 0 8px; }
p, ul, ol { margin: 0 0 16px; }
li { margin-bottom: 6px; }
.muted { color: var(--muted); }
.title { font-size: 1.1rem; color: var(--muted); margin-bottom: 24px; }
nav.top { font-size: 0.95rem; margin-bottom: 40px; }
nav.top a { text-decoration: none; }

.cards { display: grid; gap: 16px; margin: 24px 0 40px; }
.card {
  display: block;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 20px 22px;
  text-decoration: none;
  color: inherit;
  transition: border-color .15s;
}
.card:hover { border-color: var(--accent); }
.card h3 { margin: 0 0 6px; color: var(--accent); }
.card p { margin: 0; color: var(--muted); }

.links { display: flex; flex-wrap: wrap; gap: 20px; }

.meta { color: var(--muted); font-size: 0.95rem; margin-bottom: 32px; }
.callout {
  background: var(--accent-soft);
  border-left: 3px solid var(--accent);
  padding: 14px 18px;
  border-radius: 6px;
  margin: 24px 0;
}
.callout p:last-child { margin-bottom: 0; }
table { width: 100%; border-collapse: collapse; margin: 16px 0 24px; font-size: 0.95rem; }
th, td { text-align: left; padding: 10px 12px; border-bottom: 1px solid var(--border); vertical-align: top; }
th { font-weight: 600; }
.table-scroll { overflow-x: auto; }
code {
  font-family: "JetBrains Mono", ui-monospace, Consolas, monospace;
  font-size: 0.88em;
  background: var(--code-bg);
  padding: 2px 5px;
  border-radius: 4px;
}
.todo { background: #fff3c4; color: #5a4500; padding: 1px 4px; border-radius: 3px; }
@media (prefers-color-scheme: dark) { .todo { background: #4a3d00; color: #ffe38a; } }

.video { position: relative; aspect-ratio: 16 / 9; margin: 16px 0; border-radius: 10px; overflow: hidden; background: #000; }
.video iframe { position: absolute; inset: 0; width: 100%; height: 100%; border: 0; }

footer { margin-top: 64px; padding-top: 20px; border-top: 1px solid var(--border); font-size: 0.9rem; color: var(--muted); }

@media (max-width: 520px) {
  body { font-size: 16px; }
  .wrap { padding: 32px 16px 64px; }
  h1 { font-size: 1.7rem; }
}