:root {
  --bg: #ffffff;
  --bg-soft: #f6f7f9;
  --bg-code: #f2f3f5;
  --fg: #1c1f23;
  --fg-soft: #5a6068;
  --fg-mute: #8b929b;
  --line: #e3e6ea;
  --accent: #1a6b52;
  --accent-soft: #e8f3ef;
  --maxw: 46rem;
  --radius: 6px;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #16181b;
    --bg-soft: #1d2024;
    --bg-code: #21252a;
    --fg: #e6e8ea;
    --fg-soft: #a8b0b8;
    --fg-mute: #7c848c;
    --line: #2c3137;
    --accent: #4fbf9a;
    --accent-soft: #1c2a26;
  }
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-view-transition: none; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", "Source Han Sans SC", "Noto Sans CJK SC", sans-serif;
  font-size: 17px;
  line-height: 1.85;
  text-rendering: optimizeLegibility;
}
.wrap { max-width: var(--maxw); margin: 0 auto; padding: 0 1.25rem; }
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }
img, svg { max-width: 100%; height: auto; }
.skip {
  position: absolute; left: -9999px; top: 0; background: var(--fg); color: var(--bg);
  padding: .5rem .9rem; z-index: 20;
}
.skip:focus { left: .5rem; top: .5rem; }
.dot { color: var(--fg-mute); margin: 0 .45em; }

/* ---------- masthead ---------- */
.masthead {
  border-bottom: 1px solid var(--line);
  background: var(--bg);
  position: sticky; top: 0; z-index: 10;
}
.masthead-in { display: flex; align-items: center; gap: 1rem; flex-wrap: wrap; padding-top: .8rem; padding-bottom: .8rem; }
.brand { display: inline-flex; align-items: center; gap: .6rem; color: inherit; }
.brand:hover { text-decoration: none; }
.brand-mark {
  width: 22px; height: 22px; border-radius: 5px; background: var(--accent);
  display: inline-block; position: relative; flex: none;
}
.brand-mark::after {
  content: ""; position: absolute; inset: 6px 6px auto auto; width: 6px; height: 6px;
  border-radius: 50%; background: var(--bg);
}
.brand-txt { display: flex; flex-direction: column; line-height: 1.25; }
.brand-txt b { font-size: 1.02rem; font-weight: 650; letter-spacing: .01em; }
.brand-txt i { font-style: normal; font-size: .76rem; color: var(--fg-mute); }
.site-nav ul { display: flex; flex-wrap: wrap; gap: .15rem 1.15rem; list-style: none; margin: 0; padding: 0; }
.site-nav a { color: var(--fg-soft); font-size: .92rem; padding: .15rem 0; border-bottom: 2px solid transparent; }
.site-nav a:hover { color: var(--fg); text-decoration: none; }
.site-nav a.on { color: var(--accent); border-bottom-color: var(--accent); font-weight: 600; }

/* ---------- breadcrumb ---------- */
.crumb { font-size: .82rem; color: var(--fg-mute); padding: 1.1rem 0 -.4rem; }
.crumb a { color: var(--fg-mute); }
.crumb span { margin: 0 .45em; }

/* ---------- main spacing ---------- */
main { padding: 2.2rem 1.25rem 4rem; }
h1, h2, h3, h4 { line-height: 1.4; font-weight: 650; letter-spacing: -.005em; }
h1 { font-size: 1.85rem; margin: .3rem 0 1rem; }
h2 { font-size: 1.32rem; margin: 2.6rem 0 .8rem; padding-top: .2rem; }
h3 { font-size: 1.1rem; margin: 2rem 0 .6rem; }
h4 { font-size: 1rem; margin: 1.5rem 0 .4rem; color: var(--fg-soft); }
p { margin: 0 0 1.1em; }
.lead { font-size: 1.06rem; color: var(--fg-soft); }

/* ---------- hero ---------- */
.hero { padding: 1rem 0 2.4rem; border-bottom: 1px solid var(--line); margin-bottom: 2.2rem; }
.hero h1 { font-size: 2.05rem; margin-bottom: .9rem; }
.hero-meta { font-size: .84rem; color: var(--fg-mute); margin: 0; }
.notice {
  background: var(--accent-soft); border-left: 3px solid var(--accent);
  padding: .8rem 1rem; font-size: .9rem; color: var(--fg-soft); border-radius: 0 var(--radius) var(--radius) 0;
}
.notice b { color: var(--accent); }

/* ---------- section titles ---------- */
.sec {
  font-size: .8rem; letter-spacing: .12em; text-transform: uppercase; color: var(--fg-mute);
  font-weight: 600; margin: 0 0 1rem; padding: 0; border: 0;
}

/* ---------- home lists ---------- */
.rows { list-style: none; margin: 0 0 2.8rem; padding: 0; }
.rows li {
  display: grid; grid-template-columns: 1fr auto; gap: .1rem 1.2rem; align-items: baseline;
  padding: .85rem 0; border-bottom: 1px solid var(--line);
}
.rows a { color: inherit; grid-column: 1; }
.rows a:hover { color: var(--accent); text-decoration: none; }
.r-title { display: block; font-weight: 600; }
.r-desc { display: block; font-size: .88rem; color: var(--fg-mute); font-weight: 400; }
.rows time { grid-column: 2; grid-row: 1; font-size: .8rem; color: var(--fg-mute); font-variant-numeric: tabular-nums; }

.col-grid { display: grid; gap: 1.6rem 2rem; grid-template-columns: repeat(auto-fit, minmax(13rem, 1fr)); margin-bottom: 2.8rem; }
.col h3 { margin: 0 0 .5rem; font-size: 1rem; }
.col ul { list-style: none; margin: 0 0 .6rem; padding: 0; font-size: .9rem; }
.col li { padding: .28rem 0; border-bottom: 1px dashed var(--line); }
.col li a { color: var(--fg-soft); }
.more { font-size: .85rem; }
.about-brief { border-top: 1px solid var(--line); padding-top: 2.2rem; }
.more-row { display: flex; gap: .7rem; flex-wrap: wrap; margin-top: 1.3rem; }

.btn {
  display: inline-block; padding: .5rem 1.05rem; border: 1px solid var(--accent);
  border-radius: var(--radius); background: var(--accent); color: #fff; font-size: .9rem;
}
.btn:hover { text-decoration: none; opacity: .9; color: #fff; }
.btn.ghost { background: transparent; color: var(--accent); }
.btn.ghost:hover { background: var(--accent-soft); }

/* ---------- list / cards ---------- */
.list-head { padding: .6rem 0 1.6rem; border-bottom: 1px solid var(--line); margin-bottom: 1.6rem; }
.list-head h1 { margin-bottom: .5rem; }
.list-head .count { font-size: .82rem; color: var(--fg-mute); margin: 0; }
.cards { display: grid; gap: 1rem; }
.card {
  display: block; border: 1px solid var(--line); border-radius: var(--radius);
  padding: 1.05rem 1.15rem; color: inherit; background: var(--bg);
}
.card:hover { border-color: var(--accent); text-decoration: none; background: var(--bg-soft); }
.card h2 { font-size: 1.08rem; margin: 0 0 .35rem; }
.card p { font-size: .92rem; color: var(--fg-soft); margin: 0 0 .55rem; }
.card-meta { font-size: .8rem; color: var(--fg-mute); }

/* ---------- article ---------- */
.post-head { margin-bottom: 2rem; }
.kicker { font-size: .8rem; letter-spacing: .08em; margin: 0 0 .5rem; }
.kicker a { color: var(--accent); font-weight: 600; }
.post-desc { font-size: 1.05rem; color: var(--fg-soft); margin: -.3rem 0 .9rem; }
.post-meta { font-size: .84rem; color: var(--fg-mute); margin: 0; }
.post-meta em { font-style: normal; background: var(--bg-soft); border: 1px solid var(--line); border-radius: 99px; padding: .05rem .5rem; font-size: .78rem; }

.toc { background: var(--bg-soft); border: 1px solid var(--line); border-radius: var(--radius); padding: 1rem 1.2rem; margin: 0 0 2.4rem; font-size: .92rem; }
.toc h2 { font-size: .8rem; letter-spacing: .1em; text-transform: uppercase; color: var(--fg-mute); margin: 0 0 .6rem; padding: 0; border: 0; }
.toc ol { margin: 0; padding-left: 1.2rem; }
.toc li { margin: .2rem 0; }
.toc .t3 { list-style: none; margin-left: .9rem; font-size: .88rem; color: var(--fg-soft); }

.prose { }
.prose ul, .prose ol { padding-left: 1.5rem; margin: 0 0 1.2em; }
.prose li { margin: .32em 0; }
.prose strong { font-weight: 680; }
.prose hr { border: 0; border-top: 1px solid var(--line); margin: 2.4rem 0; }
.prose blockquote {
  margin: 1.4rem 0; padding: .2rem 0 .2rem 1.1rem; border-left: 3px solid var(--line);
  color: var(--fg-soft); font-size: .97rem;
}
.prose blockquote p:last-child { margin-bottom: 0; }
code {
  font-family: "SFMono-Regular", Consolas, "Liberation Mono", Menlo, "Courier New", monospace;
  font-size: .87em; background: var(--bg-code); padding: .12em .38em; border-radius: 4px;
  overflow-wrap: break-word;
}
pre.code {
  background: var(--bg-code); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 1rem 1.1rem; overflow-x: auto; line-height: 1.65; margin: 1.5rem 0;
}
pre.code code { background: none; padding: 0; font-size: .84rem; }
pre.code[data-lang] { position: relative; }
pre.code[data-lang]::before {
  content: attr(data-lang); position: absolute; top: .45rem; right: .7rem;
  font-size: .68rem; letter-spacing: .08em; text-transform: uppercase; color: var(--fg-mute);
}
.table-wrap { overflow-x: auto; margin: 1.6rem 0; }
table { border-collapse: collapse; width: 100%; font-size: .9rem; }
th, td { border: 1px solid var(--line); padding: .55rem .7rem; text-align: left; vertical-align: top; }
th { background: var(--bg-soft); font-weight: 650; }

.ai-notice {
  border: 1px solid var(--line); border-left: 3px solid var(--accent); background: var(--bg-soft);
  border-radius: 0 var(--radius) var(--radius) 0; padding: .75rem 1rem; font-size: .88rem; color: var(--fg-soft);
}
.ai-notice b { color: var(--accent); }
.post-license { font-size: .82rem; color: var(--fg-mute); border-top: 1px dashed var(--line); padding-top: 1rem; margin-top: 2.4rem; }
.post-nav { display: grid; grid-template-columns: 1fr 1fr; gap: 1rem; margin-top: 1.6rem; }
.post-nav a { border: 1px solid var(--line); border-radius: var(--radius); padding: .8rem 1rem; font-size: .92rem; display: block; }
.post-nav a:hover { border-color: var(--accent); text-decoration: none; }
.post-nav span { display: block; font-size: .76rem; color: var(--fg-mute); }
.post-nav .next { text-align: right; }

.page h1 { margin-bottom: 1.6rem; }

/* ---------- 404 ---------- */
.nf { padding: 3rem 0; text-align: left; }
.nf h1 { font-size: 3.4rem; margin-bottom: .4rem; color: var(--accent); }

/* ---------- footer ---------- */
.site-foot { border-top: 1px solid var(--line); background: var(--bg-soft); padding: 2.2rem 0 2.6rem; font-size: .85rem; color: var(--fg-mute); }
.site-foot .wrap { padding: 0 1.25rem; }
.foot-links { display: flex; flex-wrap: wrap; gap: .4rem 1.3rem; margin-bottom: 1rem; }
.foot-links a { color: var(--fg-soft); }
.foot-note { margin: 0 0 .5rem; }
.foot-beian { margin: 0 0 .5rem; }
.foot-beian a { color: var(--fg-soft); }
.foot-copy { margin: 0; }

/* ---------- narrow ---------- */
@media (max-width: 640px) {
  body { font-size: 16px; }
  h1 { font-size: 1.55rem; }
  .hero h1 { font-size: 1.7rem; }
  .masthead-in { padding-top: .7rem; padding-bottom: .7rem; }
  .site-nav { width: 100%; }
  .site-nav ul { gap: .2rem 1rem; }
  main { padding-top: 1.6rem; }
  .rows li { grid-template-columns: 1fr; }
  .rows time { grid-column: 1; grid-row: 2; }
  .post-nav { grid-template-columns: 1fr; }
  .post-nav .next { text-align: left; }
}
@media print {
  .masthead, .site-foot, .toc, .post-nav { display: none; }
  body { font-size: 11pt; }
}