:root {
  --bg: #fbfaf7; --surface: #ffffff; --text: #1d1f23; --muted: #5d636e; --line: #e4e1da;
  --accent: #0f6e5c; --accent-soft: #e3f1ed; --todo-bg: #fff3c4; --todo-text: #6b4e00;
  color-scheme: light dark;
}
@media (prefers-color-scheme: dark) {
  :root { --bg: #14161a; --surface: #1b1e23; --text: #e8e6e1; --muted: #a0a6b0; --line: #2c3037;
    --accent: #5cc4ad; --accent-soft: #1d302c; --todo-bg: #4a3b0a; --todo-text: #ffe28a; }
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body { margin: 0; background: var(--bg); color: var(--text);
  font: 16px/1.7 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", "PingFang SC", "Microsoft YaHei", sans-serif; }
a { color: var(--accent); }
.wrap { max-width: 880px; margin: 0 auto; padding: 0 20px; }
header.top { border-bottom: 1px solid var(--line); background: var(--surface); }
header.top .wrap { display: flex; align-items: center; justify-content: space-between; gap: 16px; min-height: 64px; flex-wrap: wrap; }
.brand { display: flex; align-items: center; gap: 10px; font-weight: 700; font-size: 18px; color: var(--text); text-decoration: none; }
.brand img { width: 28px; height: 28px; }
nav.links { display: flex; gap: 18px; flex-wrap: wrap; font-size: 15px; }
nav.links a { text-decoration: none; }
nav.links a:hover { text-decoration: underline; }
main { padding: 40px 0 64px; }
h1 { font-size: 34px; line-height: 1.25; margin: 0 0 12px; letter-spacing: -0.01em; }
h2 { font-size: 22px; margin: 40px 0 10px; }
h3 { font-size: 17px; margin: 24px 0 6px; }
p, li { color: var(--text); }
.lead { font-size: 19px; color: var(--muted); max-width: 680px; }
.meta { color: var(--muted); font-size: 14px; }
.note { background: var(--accent-soft); border-radius: 10px; padding: 14px 18px; margin: 20px 0; }
.grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 16px; margin: 20px 0; }
.card { background: var(--surface); border: 1px solid var(--line); border-radius: 12px; padding: 18px 20px; }
.card h3 { margin-top: 0; }
.card p { margin: 0; color: var(--muted); font-size: 15px; }
ol.flow { padding-left: 22px; }
ol.flow li { margin: 6px 0; }
table { width: 100%; border-collapse: collapse; margin: 14px 0; font-size: 15px; }
th, td { text-align: left; vertical-align: top; border-bottom: 1px solid var(--line); padding: 10px 8px; }
th { color: var(--muted); font-weight: 600; }
.table-scroll { overflow-x: auto; }
.todo { background: var(--todo-bg); color: var(--todo-text); border-radius: 4px; padding: 0 4px; font-weight: 600; }
footer.bottom { border-top: 1px solid var(--line); background: var(--surface); padding: 24px 0; font-size: 14px; color: var(--muted); }
footer.bottom .wrap { display: flex; justify-content: space-between; gap: 12px; flex-wrap: wrap; }
footer.bottom a { margin-right: 16px; }
@media (max-width: 560px) { h1 { font-size: 27px; } main { padding-top: 28px; } }