:root {
  color-scheme: light;
  --ink: #292f36;
  --muted: #68717c;
  --line: #e4e8ed;
  --accent: #a8413a;
  --paper: #fff;
}
* {
  box-sizing: border-box;
}
html {
  scroll-behavior: smooth;
  scroll-padding-top: 24px;
}
body {
  margin: 0;
  color: var(--ink);
  background: #f5f6f8;
  font:
    16px / 1.85 -apple-system,
    BlinkMacSystemFont,
    "Segoe UI",
    "PingFang SC",
    "Microsoft YaHei",
    sans-serif;
}
a {
  color: var(--accent);
  text-underline-offset: 4px;
  overflow-wrap: anywhere;
}
a:hover {
  text-decoration-thickness: 2px;
}
a:focus-visible {
  outline: 3px solid #a8413a66;
  outline-offset: 4px;
  border-radius: 2px;
}
.skip {
  position: absolute;
  left: 20px;
  top: -80px;
  padding: 8px 14px;
  background: #fff;
  z-index: 2;
}
.skip:focus {
  top: 12px;
}
.shell {
  width: min(1040px, calc(100% - 48px));
  margin-inline: auto;
}
.topbar {
  background: var(--paper);
  border-bottom: 1px solid var(--line);
}
.topbar .shell {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  padding-block: 18px;
}
.brand {
  color: var(--ink);
  font-weight: 650;
  text-decoration: none;
  letter-spacing: 0.02em;
}
.topbar nav {
  display: flex;
  gap: 22px;
  font-size: 14px;
}
.topbar nav a {
  color: var(--muted);
  text-decoration: none;
}
.topbar nav a[aria-current="page"] {
  color: var(--accent);
  font-weight: 650;
}
.hero {
  padding: 48px 0 28px;
}
.eyebrow {
  margin: 0 0 9px;
  color: var(--accent);
  font-size: 13px;
  font-weight: 650;
  letter-spacing: 0.12em;
}
h1 {
  margin: 0 0 14px;
  font-size: clamp(28px, 4.3vw, 40px);
  line-height: 1.35;
  letter-spacing: -0.02em;
}
.subtitle,
.meta {
  color: var(--muted);
}
.subtitle {
  max-width: 780px;
  margin: 0;
}
.meta {
  margin: 18px 0 0;
  font-size: 13px;
}
.layout {
  display: grid;
  grid-template-columns: 200px minmax(0, 1fr);
  gap: 28px;
  align-items: start;
  padding-bottom: 48px;
}
.toc {
  position: sticky;
  top: 24px;
  padding: 20px;
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: 12px;
  font-size: 14px;
}
.toc strong {
  display: block;
  margin-bottom: 10px;
}
.toc a {
  display: block;
  padding: 4px 0;
  color: var(--muted);
  text-decoration: none;
}
.toc a:hover {
  color: var(--accent);
}
article {
  min-width: 0;
  padding: 30px 36px;
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: 12px;
}
section + section {
  border-top: 1px solid var(--line);
  margin-top: 30px;
  padding-top: 26px;
}
h2 {
  margin: 0 0 14px;
  font-size: 21px;
  line-height: 1.5;
}
h3 {
  margin: 18px 0 6px;
  font-size: 16px;
}
p {
  margin: 0 0 14px;
}
ul,
ol {
  margin: 8px 0 18px;
  padding-left: 24px;
}
li {
  margin: 7px 0;
}
.notice {
  padding: 18px 20px;
  margin-bottom: 26px;
  background: #fff7ed;
  border: 1px solid #f0d7b5;
  border-left: 4px solid #c18236;
  border-radius: 8px;
}
.notice strong {
  display: block;
  margin-bottom: 5px;
}
.notice p:last-child,
section p:last-child {
  margin-bottom: 0;
}
.table-wrap {
  overflow-x: auto;
  margin: 16px 0;
}
table {
  width: 100%;
  border-collapse: collapse;
  font-size: 14px;
}
th,
td {
  text-align: left;
  vertical-align: top;
  padding: 12px;
  border-bottom: 1px solid var(--line);
}
th {
  background: #f7f8fa;
  white-space: nowrap;
}
code {
  font:
    0.9em / 1.6 ui-monospace,
    SFMono-Regular,
    Consolas,
    monospace;
  background: #f2f4f6;
  padding: 2px 5px;
  border-radius: 4px;
  overflow-wrap: anywhere;
}
.contact {
  padding: 18px 20px;
  background: #f8f9fb;
  border-radius: 8px;
}
footer {
  border-top: 1px solid var(--line);
  padding: 24px 0 32px;
  color: var(--muted);
  font-size: 13px;
}
footer .shell {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
}
@media (max-width: 760px) {
  .shell {
    width: calc(100% - 32px);
  }
  .topbar .shell {
    align-items: flex-start;
    flex-direction: column;
    gap: 8px;
  }
  .hero {
    padding-top: 30px;
  }
  .layout {
    grid-template-columns: minmax(0, 1fr);
    gap: 18px;
  }
  .toc {
    position: static;
  }
  .toc a {
    display: inline-block;
    margin-right: 18px;
  }
  article {
    padding: 24px 20px;
  }
  body {
    font-size: 15px;
  }
}
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
}
@media print {
  body {
    background: #fff;
    font-size: 11pt;
  }
  .topbar,
  .toc,
  .skip {
    display: none;
  }
  .layout {
    display: block;
  }
  article {
    border: 0;
    padding: 0;
  }
  .shell {
    width: 100%;
  }
}