:root {
  color-scheme: light;
  --background: #f4f7f8;
  --surface: #ffffff;
  --text: #1d2b33;
  --muted: #5c6e78;
  --primary: #315f78;
  --primary-dark: #24495d;
  --border: #d7e0e4;
  --code-background: #eef3f5;
}

* {
  box-sizing: border-box;
}
html {
  scroll-behavior: smooth;
}
body {
  max-width: 980px;
  margin: 0 auto;
  padding: 3rem clamp(1.25rem, 4vw, 4rem) 5rem;
  background: var(--background);
  color: var(--text);
  font-family: 'Microsoft YaHei', 'Noto Sans CJK SC', system-ui, sans-serif;
  font-size: 17px;
  line-height: 1.75;
}
body::before {
  display: block;
  margin-bottom: 1.25rem;
  color: var(--primary);
  content: '计算机图形学 · 2026 秋季';
  font-size: 0.85rem;
  font-weight: 700;
  letter-spacing: 0.12em;
}
h1,
h2,
h3,
h4 {
  color: var(--primary-dark);
  line-height: 1.35;
  text-wrap: balance;
}
h1 {
  margin: 0 0 1.5rem;
  padding-bottom: 1rem;
  border-bottom: 3px solid var(--primary);
  font-size: clamp(2rem, 5vw, 3rem);
}
h2 {
  margin-top: 2.75rem;
  padding-bottom: 0.45rem;
  border-bottom: 1px solid var(--border);
  font-size: 1.55rem;
}
h3 {
  margin-top: 2rem;
  font-size: 1.2rem;
}
a {
  color: var(--primary);
  text-underline-offset: 0.2em;
}
a:hover {
  color: var(--primary-dark);
}
nav#TOC {
  margin: 1.5rem 0 2.5rem;
  padding: 1rem 1.4rem;
  border: 1px solid var(--border);
  border-radius: 0.75rem;
  background: var(--surface);
}
nav#TOC::before {
  content: '目录';
  font-weight: 700;
}
nav#TOC ul {
  margin: 0.5rem 0 0;
}
blockquote {
  margin: 1.5rem 0;
  padding: 0.85rem 1.1rem;
  border-left: 4px solid var(--primary);
  background: var(--surface);
  color: var(--muted);
}
table {
  display: block;
  width: 100%;
  margin: 1.5rem 0;
  overflow-x: auto;
  border-collapse: collapse;
  background: var(--surface);
}
th,
td {
  padding: 0.7rem 0.85rem;
  border: 1px solid var(--border);
  text-align: left;
  vertical-align: top;
}
th {
  background: #e7eff3;
}
pre,
code {
  font-family: 'Cascadia Code', Consolas, monospace;
}
code {
  padding: 0.1em 0.3em;
  border-radius: 0.25rem;
  background: var(--code-background);
  font-size: 0.9em;
}
pre {
  overflow-x: auto;
  padding: 1rem;
  border: 1px solid var(--border);
  border-radius: 0.6rem;
  background: var(--code-background);
  line-height: 1.55;
}
pre code {
  padding: 0;
  background: transparent;
}
li {
  margin: 0.3rem 0;
}
input[type='checkbox'] {
  margin-right: 0.45rem;
}
@media (max-width: 640px) {
  body {
    padding-top: 1.5rem;
    font-size: 16px;
  }
  h1 {
    font-size: 1.9rem;
  }
}
@media print {
  body {
    max-width: none;
    padding: 0;
    background: #fff;
    font-size: 11pt;
  }
  nav#TOC {
    break-after: page;
  }
  a {
    color: inherit;
  }
}