/* Homepage — minimal white/black theme. */

:root {
  --text: #1a1a1a;
  --muted: #777;
  --line: #e4e4e4;
  --accent: #0645ad;
}

* { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0 auto;
  max-width: 42em;
  padding: 1.5em 1.25em 3em;
  color: var(--text);
  background: #fff;
  font: 16px/1.75 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto,
        "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
}

a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

/* ---------- header / nav ---------- */
.site-nav {
  display: flex;
  align-items: baseline;
  gap: 1.25em;
  padding-bottom: 0.75em;
  margin-bottom: 2.5em;
  border-bottom: 1px solid var(--line);
}
.site-nav ul {
  display: flex;
  gap: 1.25em;
  list-style: none;
  margin: 0;
  padding: 0;
}
.site-nav a.active { color: var(--text); font-weight: 600; }
.lang-switch { margin-left: auto; font-size: 0.95em; }

/* ---------- content ---------- */
main h1 { font-size: 1.55em; line-height: 1.3; margin: 0 0 1em; }
main h2 { font-size: 1.2em; margin: 2em 0 0.75em; }
main h3 { font-size: 1.05em; margin: 1.6em 0 0.5em; }
main p, main ul, main ol { margin: 0 0 1em; }
main li { margin: 0.25em 0; }
main img { max-width: 100%; }
main hr { border: none; border-top: 1px solid var(--line); margin: 2.5em 0; }

main code {
  font: 0.9em ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  background: #f4f4f4;
  padding: 0.1em 0.35em;
  border-radius: 3px;
}
main pre {
  background: #f4f4f4;
  padding: 0.9em 1em;
  overflow-x: auto;
  border-radius: 4px;
}
main pre code { background: none; padding: 0; }

main blockquote {
  margin: 0 0 1em;
  padding-left: 1em;
  color: var(--muted);
  border-left: 2px solid var(--line);
}

main table { border-collapse: collapse; width: 100%; margin: 0 0 1em; }
main th, main td {
  border: 1px solid var(--line);
  padding: 0.4em 0.7em;
  text-align: left;
}
main th { background: #fafafa; }

/* ---------- essay list ---------- */
.essay-list { margin-top: 2.5em; }
.essay-list h2 { margin-top: 0; }
.essay-list ul { list-style: none; padding: 0; }
.essay-list li { padding: 0.35em 0; border-bottom: 1px solid var(--line); }
.essay-list .date { color: var(--muted); font-size: 0.9em; margin-left: 0.8em; }
.badge {
  display: inline-block;
  margin-left: 0.6em;
  padding: 0 0.45em;
  border: 1px solid var(--line);
  border-radius: 3px;
  color: var(--muted);
  font-size: 0.78em;
  vertical-align: middle;
}

/* ---------- footer ---------- */
.site-footer {
  margin-top: 4em;
  padding-top: 1em;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 0.88em;
}
.site-footer p { margin: 0; }
.site-footer a { color: var(--muted); text-decoration: underline; }

/* ---------- publications on the homepage ---------- */
/* 论文条目：标题 / 作者 / 出处各成一行，条目之间留白 */
main > ul > li + li { margin-top: 0.9em; }
main li > p { margin: 0.15em 0; }
main li > p:first-child { margin-top: 0; }
main li > p:last-child { margin-bottom: 0; }
main sup { font-size: 0.72em; line-height: 0; }
.pub-legend { font-size: 0.85em; color: var(--muted); }

/* ---------- 数学公式（构建时渲染的 MathML） ---------- */
.math.block { margin: 1.2em 0; overflow-x: auto; }
.math.inline { white-space: nowrap; }

/* ---------- 脚注 ---------- */
.footnotes { margin-top: 2.5em; padding-top: 0.8em; border-top: 1px solid var(--line); font-size: 0.88em; color: var(--muted); }
.footnotes-sep { display: none; }
.footnote-ref a { text-decoration: none; }
.footnote-backref { text-decoration: none; }