:root {
  --bg: #f6f7fb;
  --panel: #ffffff;
  --text: #121826;
  --muted: #5b6475;
  --accent: #1c4acd;
  --line: #e3e7ef;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #070b16;
    --panel: #111827;
    --text: #eef2f8;
    --muted: #9aa4b5;
    --accent: #4d8dff;
    --line: #1f2a3d;
  }
}
* { box-sizing: border-box; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 17px/1.6 -apple-system, BlinkMacSystemFont, "SF Pro Text", "Segoe UI", Roboto, sans-serif;
}
main { max-width: 760px; margin: 0 auto; padding: 28px 16px 56px; }
header { display: flex; align-items: center; gap: 14px; margin-bottom: 8px; }
header img { width: 56px; height: 56px; border-radius: 13px; }
header h1 { font-size: 26px; margin: 0; line-height: 1.2; }
header p { margin: 2px 0 0; color: var(--muted); font-size: 15px; }
nav { display: flex; flex-wrap: wrap; gap: 8px; margin: 18px 0 26px; }
nav a {
  padding: 7px 14px; border-radius: 999px; border: 1px solid var(--line);
  background: var(--panel); color: var(--accent); text-decoration: none; font-weight: 600; font-size: 15px;
}
section { background: var(--panel); border: 1px solid var(--line); border-radius: 18px; padding: 22px 22px 8px; margin-bottom: 18px; }
h2 { font-size: 21px; margin: 0 0 6px; }
h3 { font-size: 17px; margin: 18px 0 4px; }
p, li { color: var(--text); }
.muted { color: var(--muted); font-size: 15px; }
a { color: var(--accent); }
ul { padding-left: 22px; }
footer { color: var(--muted); font-size: 14px; text-align: center; margin-top: 28px; }