:root {
  --ink: #16181d;
  --muted: #5b6270;
  --line: #e3e6ec;
  --bg: #ffffff;
  --accent: #1f3a8a;
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font: 16px/1.65 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}
.wrap { max-width: 720px; margin: 0 auto; padding: 0 16px; }
header { border-bottom: 1px solid var(--line); padding: 20px 0; }
header .wrap { display: flex; align-items: center; justify-content: space-between; gap: 16px; flex-wrap: wrap; }
.brand { font-weight: 600; font-size: 17px; text-decoration: none; color: var(--ink);
         display: inline-flex; align-items: center; gap: 9px; }
.brand img { display: block; }
nav a { color: var(--muted); text-decoration: none; margin-left: 18px; font-size: 15px; }
nav a:hover, .brand:hover { color: var(--accent); }
main { padding: 40px 0 56px; }
h1 { font-size: 30px; line-height: 1.25; margin: 0 0 16px; font-weight: 600; letter-spacing: -0.01em; }
h2 { font-size: 20px; margin: 36px 0 10px; font-weight: 600; }
h3 { font-size: 17px; margin: 24px 0 8px; font-weight: 600; }
p, li { color: var(--ink); }
.lead { font-size: 18px; color: var(--muted); margin: 0 0 28px; }
ul { padding-left: 20px; }
li { margin: 6px 0; }
code { background: #f4f5f8; padding: 2px 5px; border-radius: 4px; font-size: 14px; word-break: break-all; }
.meta { color: var(--muted); font-size: 14px; }
.box { border: 1px solid var(--line); border-radius: 8px; padding: 18px 20px; margin: 24px 0; background: #fafbfc; }
.box p:first-child { margin-top: 0; }
.box p:last-child { margin-bottom: 0; }
footer { border-top: 1px solid var(--line); padding: 24px 0 40px; color: var(--muted); font-size: 14px; }
footer a { color: var(--muted); }
a { color: var(--accent); }
@media (max-width: 480px) {
  h1 { font-size: 25px; }
  nav a { margin: 0 14px 0 0; }
  header .wrap { gap: 10px; }
}