:root{
  --bg:#fbfbf9; --fg:#1b1b1b; --muted:#6b6b6b; --line:#e3e3dc;
  --accent:#0b5d8a; --code-bg:#f3f3ee; --note-bg:#f6f7f2;
}
@media (prefers-color-scheme:dark){
  :root{ --bg:#15171b; --fg:#e6e5e0; --muted:#9aa0a6; --line:#2b2f36;
    --accent:#79b8d8; --code-bg:#1c2027; --note-bg:#1b1f25; }
}
*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%}
body{
  margin:0; background:var(--bg); color:var(--fg);
  font:16px/1.75 -apple-system,BlinkMacSystemFont,"Segoe UI","Noto Sans SC","PingFang SC","Hiragino Sans GB","Microsoft YaHei",sans-serif;
}
a{color:var(--accent);text-decoration:none}
a:hover{text-decoration:underline}
header{
  border-bottom:1px solid var(--line); background:var(--bg);
  position:sticky; top:0; z-index:10;
}
.wrap{max-width:780px;margin:0 auto;padding:0 22px}
header .wrap{display:flex;align-items:center;justify-content:space-between;height:58px;gap:18px}
.brand{font:600 15px/1 ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;color:var(--fg);letter-spacing:.02em}
.brand:hover{text-decoration:none;color:var(--accent)}
nav{display:flex;gap:18px;font-size:14px}
nav a{color:var(--muted)}
nav a:hover{color:var(--fg);text-decoration:none}
main{padding:44px 0 64px}
h1{font-size:clamp(24px,4vw,31px);line-height:1.35;margin:0 0 10px;letter-spacing:-.01em;font-weight:650}
h2{font-size:19px;margin:38px 0 12px;font-weight:600}
h3{font-size:16px;margin:26px 0 8px;font-weight:600}
p{margin:0 0 16px}
.lead{color:var(--muted);font-size:17px;margin-bottom:34px}
.meta{color:var(--muted);font-size:13px;margin-bottom:34px}
.meta span+span::before{content:"·";margin:0 8px}
ul.list{list-style:none;padding:0;margin:0}
ul.list li{border-top:1px solid var(--line);padding:18px 0}
ul.list li:last-child{border-bottom:1px solid var(--line)}
ul.list .t{font-weight:600;font-size:17px}
ul.list .d{color:var(--muted);font-size:14px;margin-top:4px}
ul.list a{color:var(--fg)}
.tag{display:inline-block;font:12px/1 ui-monospace,monospace;color:var(--muted);
  border:1px solid var(--line);border-radius:4px;padding:4px 6px;margin-left:8px;vertical-align:2px}
code{font-family:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;font-size:13.5px;
  background:var(--code-bg);padding:2px 5px;border-radius:3px}
pre{background:var(--code-bg);border:1px solid var(--line);border-radius:6px;
  padding:14px 16px;overflow:auto;margin:0 0 18px}
pre code{background:none;padding:0;font-size:13px;line-height:1.65}
blockquote{margin:0 0 18px;padding:2px 0 2px 16px;border-left:3px solid var(--line);color:var(--muted)}
.note{background:var(--note-bg);border:1px solid var(--line);border-radius:6px;padding:14px 16px;margin:0 0 18px;font-size:14.5px}
.note b{font-weight:600}
table{width:100%;border-collapse:collapse;margin:0 0 20px;font-size:14.5px}
th,td{text-align:left;padding:8px 10px;border-bottom:1px solid var(--line)}
th{font-weight:600;color:var(--muted);font-size:13px}
footer{border-top:1px solid var(--line);color:var(--muted);font-size:13px;padding:22px 0 40px}
footer .wrap{display:flex;justify-content:space-between;gap:14px;flex-wrap:wrap}
hr{border:0;border-top:1px solid var(--line);margin:34px 0}
.back{font-size:14px;color:var(--muted)}