:root {
  color-scheme: light;
  --fg: #1b1f24; --muted: #57606a; --bg: #ffffff; --bg-alt: #f6f8fa;
  --border: #d0d7de; --accent: #0969da; --accent-bg: #ddf4ff;
  --code-bg: #0d1117; --code-fg: #e6edf3;
  font-size: 17px;
}
* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  color: var(--fg); background: var(--bg); line-height: 1.6;
}
.wrap { max-width: 860px; margin: 0 auto; padding: 0 1.25rem; }
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }
.site-header { border-bottom: 1px solid var(--border); background: var(--bg-alt); }
.site-header .wrap { display: flex; flex-wrap: wrap; align-items: center; gap: 0.75rem 1.25rem; padding: 0.9rem 1.25rem; }
.brand { font-weight: 700; color: var(--fg); margin-right: auto; }
.site-header nav { display: flex; flex-wrap: wrap; gap: 0.25rem 1rem; }
.site-header nav a { color: var(--muted); font-size: 0.95rem; white-space: nowrap; }
.site-header nav a.active { color: var(--accent); font-weight: 600; }
main { padding: 2rem 1.25rem 3rem; }
h1 { font-size: 1.9rem; line-height: 1.25; margin: 0 0 0.75rem; }
h2 { font-size: 1.4rem; margin-top: 2.25rem; border-bottom: 1px solid var(--border); padding-bottom: 0.3rem; }
h3 { font-size: 1.1rem; margin-top: 1.75rem; }
p { margin: 0.9rem 0; }
.deadline { display: inline-block; background: var(--accent-bg); border: 1px solid var(--border); border-radius: 6px; padding: 0.5rem 0.9rem; font-weight: 600; }
.updated { color: var(--muted); font-size: 0.85rem; margin: 0 0 1rem; }
.notice { background: #fff8c5; border: 1px solid #d4a72c; border-radius: 6px; padding: 0.75rem 1rem; margin: 1rem 0; }
ul, ol { padding-left: 1.4rem; }
li { margin: 0.35rem 0; }
blockquote { margin: 1rem 0; padding: 0.4rem 1rem; border-left: 3px solid var(--accent); background: var(--bg-alt); color: var(--muted); }
code { background: var(--bg-alt); border: 1px solid var(--border); border-radius: 4px; padding: 0.1rem 0.35rem; font-size: 0.88em; font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace; }
.table-wrap { overflow-x: auto; margin: 1rem 0; }
table { border-collapse: collapse; width: 100%; font-size: 0.95rem; }
th, td { border: 1px solid var(--border); padding: 0.5rem 0.7rem; text-align: left; vertical-align: top; }
th { background: var(--bg-alt); }
.codeblock { position: relative; margin: 1rem 0; border-radius: 8px; overflow: hidden; background: var(--code-bg); }
.codeblock pre { margin: 0; padding: 1rem; overflow-x: auto; }
.codeblock code { background: none; border: none; padding: 0; color: var(--code-fg); font-size: 0.88rem; }
.codeblock .code-lang { position: absolute; top: 0.5rem; left: 0.9rem; color: #8b949e; font-size: 0.75rem; text-transform: uppercase; letter-spacing: 0.04em; }
.codeblock .copy-btn {
  position: absolute; top: 0.5rem; right: 0.6rem; z-index: 1;
  background: #21262d; color: #c9d1d9; border: 1px solid #30363d; border-radius: 6px;
  font-size: 0.75rem; padding: 0.25rem 0.6rem; cursor: pointer;
}
.codeblock .copy-btn:hover { background: #30363d; }
.codeblock .copy-btn.copied { background: #238636; color: #fff; border-color: #238636; }
.site-footer { border-top: 1px solid var(--border); background: var(--bg-alt); color: var(--muted); font-size: 0.9rem; }
.site-footer .wrap { padding: 1.25rem; }
@media (max-width: 600px) {
  :root { font-size: 16px; }
  h1 { font-size: 1.5rem; }
}