:root {
  --ink: #16202b;
  --muted: #5a6776;
  --line: #e3e7ec;
  --bg: #ffffff;
  --soft: #f5f7f9;
  --accent: #0f766e;
  --accent-ink: #ffffff;
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font: 17px/1.6 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}
a { color: var(--accent); }
.wrap { max-width: 860px; margin: 0 auto; padding: 0 20px; }
header { border-bottom: 1px solid var(--line); }
header .wrap { display: flex; align-items: center; justify-content: space-between; gap: 16px; padding-top: 18px; padding-bottom: 18px; flex-wrap: wrap; }
.brand { font-weight: 700; font-size: 20px; color: var(--ink); text-decoration: none; letter-spacing: -0.01em; }
nav a { color: var(--muted); text-decoration: none; margin-left: 18px; font-size: 15px; }
nav a:first-child { margin-left: 0; }
nav a:hover { color: var(--ink); }
.hero { padding: 64px 0 40px; }
.hero h1 { font-size: clamp(30px, 5vw, 44px); line-height: 1.15; margin: 0 0 16px; letter-spacing: -0.02em; }
.hero p { font-size: 19px; color: var(--muted); max-width: 640px; margin: 0 0 28px; }
.button { display: inline-block; background: var(--accent); color: var(--accent-ink); padding: 12px 20px; border-radius: 8px; text-decoration: none; font-weight: 600; }
section { padding: 36px 0; }
section + section { border-top: 1px solid var(--line); }
h2 { font-size: 24px; margin: 0 0 14px; letter-spacing: -0.01em; }
h3 { font-size: 18px; margin: 24px 0 8px; }
.grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 16px; }
.card { background: var(--soft); border: 1px solid var(--line); border-radius: 10px; padding: 18px; }
.card h3 { margin-top: 0; }
.card p { margin: 0; color: var(--muted); font-size: 16px; }
.doc { padding: 48px 0; }
.doc h1 { font-size: 32px; margin: 0 0 6px; }
.doc .updated { color: var(--muted); margin: 0 0 28px; font-size: 15px; }
.doc li { margin-bottom: 6px; }
.callout { background: var(--soft); border-left: 4px solid var(--accent); padding: 14px 18px; border-radius: 6px; margin: 18px 0; }
footer { border-top: 1px solid var(--line); color: var(--muted); font-size: 14px; }
footer .wrap { padding-top: 24px; padding-bottom: 32px; display: flex; gap: 18px; flex-wrap: wrap; justify-content: space-between; }
footer a { color: var(--muted); }