:root {
  --bg: #F6F7F9; --card: #FFFFFF; --text: #1B1F24; --muted: #5B6470; --line: #E3E7EC;
  --accent: #2D66D3; --accent-text: #FFFFFF;
}
@media (prefers-color-scheme: dark) {
  :root { --bg: #111316; --card: #1B1E23; --text: #E9EDF2; --muted: #A2ABB6; --line: #2A2F36; --accent: #5C9BF5; --accent-text: #0E1013; }
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body { margin: 0; background: var(--bg); color: var(--text);
  font: 17px/1.6 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif; }
main { max-width: 720px; margin: 0 auto; padding: 32px 16px 64px; }
header { display: flex; align-items: center; gap: 14px; margin-bottom: 28px; }
header img { width: 56px; height: 56px; border-radius: 13px; }
header a { color: inherit; text-decoration: none; }
header .brand { font-weight: 700; font-size: 22px; letter-spacing: .02em; }
header .sub { color: var(--muted); font-size: 15px; }
h1 { font-size: 30px; line-height: 1.2; margin: 0 0 6px; }
h2 { font-size: 20px; margin: 32px 0 8px; }
.updated { color: var(--muted); margin: 0 0 20px; font-size: 15px; }
.card { background: var(--card); border: 1px solid var(--line); border-radius: 16px; padding: 20px; margin: 16px 0; }
ul { padding-left: 22px; } li { margin: 6px 0; }
a { color: var(--accent); }
.button { display: inline-block; background: var(--accent); color: var(--accent-text); text-decoration: none;
  font-weight: 600; padding: 12px 20px; border-radius: 12px; margin-top: 4px; }
nav { margin-top: 40px; padding-top: 20px; border-top: 1px solid var(--line); display: flex; flex-wrap: wrap; gap: 18px; font-size: 15px; }
footer { color: var(--muted); font-size: 14px; margin-top: 16px; }