:root {
  --op-paper: #eef1f7;
  --op-ink: #1a2440;
  --op-red: #c4352b;
  --op-blue: #24479a;
  --op-line: #cfd6e6;
  --op-card: #ffffff;
  --op-muted: #4a5573;
  --op-soft: #e3e8f2;
  --op-r: 5px;
  --op-r2: 2px;
  --op-latin: "Lucida Bright", "Bookman Old Style", serif;
  --op-cjk: "PingFang SC", "Microsoft YaHei", "Noto Sans SC", sans-serif;
  --op-stripe: repeating-linear-gradient(135deg, var(--op-red) 0 12px, transparent 12px 19px, var(--op-blue) 19px 31px, transparent 31px 38px);
  --op-h1: 47px;
}

*, *::before, *::after { box-sizing: border-box; }

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

body {
  margin: 0;
  background: var(--op-paper);
  color: var(--op-ink);
  font-family: var(--op-cjk);
  font-size: 16px;
  line-height: 1.8;
  overflow-wrap: break-word;
}

img { max-width: 100%; height: auto; }

a { color: var(--op-blue); text-decoration-thickness: 1px; text-underline-offset: 3px; }
a:hover { color: var(--op-red); }

:focus-visible { outline: 2px solid var(--op-red); outline-offset: 2px; border-radius: var(--op-r2); }

h1, h2, h3 { font-family: var(--op-cjk); line-break: strict; color: var(--op-ink); }

h1 { font-size: var(--op-h1); line-height: 1.22; margin: 0 0 18px; font-weight: 700; letter-spacing: 0; }

code { font-family: var(--op-latin); font-size: .95em; background: var(--op-soft); padding: 1px 5px; border-radius: var(--op-r2); overflow-wrap: anywhere; }

.op-latin { font-family: var(--op-latin); }

.op-skip {
  position: absolute; left: 12px; top: -60px; z-index: 20;
  background: var(--op-ink); color: #fff; padding: 10px 16px; border-radius: var(--op-r2);
  min-height: 44px; display: inline-flex; align-items: center;
}
.op-skip:focus { top: 12px; color: #fff; }

.op-sr { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); clip-path: inset(50%); white-space: nowrap; margin: 0; }

/* 页头 */
.op-top { background: var(--op-card); border-bottom: 1px solid var(--op-line); }
.op-top::before { content: ""; display: block; height: 4px; background: var(--op-stripe); }
.op-top-in { max-width: 1120px; margin: 0 auto; padding: 6px 24px; display: flex; align-items: center; justify-content: space-between; gap: 12px; }
.op-brand { display: inline-flex; align-items: center; min-height: 44px; color: var(--op-ink); text-decoration: none; }
.op-brand:hover { color: var(--op-ink); }
.op-logo { display: block; width: 128px; height: 32px; }
.op-logo-word { font-family: var(--op-latin); font-size: 23px; font-weight: 700; letter-spacing: .01em; }
.op-nav { display: flex; gap: 4px; }
.op-nav a {
  display: inline-flex; align-items: center; min-height: 44px; padding: 0 12px;
  color: var(--op-ink); text-decoration: none; border-radius: var(--op-r2); font-size: 15px;
}
.op-nav a:hover { background: var(--op-soft); color: var(--op-ink); }
.op-nav a[aria-current="page"] { color: var(--op-red); box-shadow: inset 0 -2px 0 var(--op-red); }

.op-main { display: block; }
.op-wrap { max-width: 760px; margin: 0 auto; padding: 28px 24px 64px; }

/* 首页首屏 */
.op-hero {
  max-width: 1120px; margin: 0 auto; padding: 52px 24px 40px;
  display: grid; grid-template-columns: minmax(0, 1fr) 444px; column-gap: 56px; row-gap: 18px;
  grid-template-areas: "h env" "lead env" "rec env" ". env";
  align-items: start;
}
.op-hero-h { grid-area: h; margin: 0; max-width: 10.6em; }
.op-hero-lead { grid-area: lead; margin: 0; font-size: 17px; color: var(--op-muted); max-width: 34em; }
.op-hero .op-env { grid-area: env; }
.op-rec { grid-area: rec; background: var(--op-card); border: 1px solid var(--op-line); border-radius: var(--op-r); padding: 18px 20px 16px; max-width: 34em; }
.op-rec-k { margin: 0 0 4px; font-size: 14px; color: var(--op-red); font-weight: 700; display: flex; align-items: center; gap: 8px; }
.op-rec-k::before { content: ""; width: 10px; height: 10px; border: 2px solid var(--op-red); border-radius: 50%; }
.op-rec-t { margin: 0 0 6px; font-size: 19px; line-height: 1.5; font-weight: 700; }
.op-rec-t a { color: var(--op-ink); text-decoration-color: var(--op-blue); }
.op-rec-t a:hover { color: var(--op-blue); }
.op-rec-d { margin: 0; font-size: 15px; color: var(--op-muted); }

/* 信封码卡 */
.op-env {
  position: relative; padding: 11px; border-radius: var(--op-r);
  background: var(--op-stripe), #fff;
  box-shadow: 0 1px 0 var(--op-line), 0 22px 40px -26px rgba(26, 36, 64, .55);
}
.op-env-in { position: relative; background: var(--op-card); border-radius: var(--op-r2); padding: 20px 22px 18px; }
.op-stamp {
  position: absolute; top: 14px; right: 14px; width: 64px; height: 76px; padding: 5px;
  background: radial-gradient(circle, #fff 2.3px, transparent 2.8px) -4px -4px / 8px 8px, #d9e1f0;
}
.op-stamp-face { display: flex; align-items: center; justify-content: center; width: 100%; height: 100%; background: var(--op-blue); }
.op-stamp-face img { width: 40px; height: 40px; display: block; }
.op-postmark {
  position: absolute; top: 28px; right: 66px; width: 70px; height: 70px; border: 2px solid var(--op-red); border-radius: 50%;
  display: flex; flex-direction: column; align-items: center; justify-content: center; line-height: 1.15;
  font-family: var(--op-latin); font-size: 10px; letter-spacing: 0; color: var(--op-red); transform: rotate(-14deg); opacity: .85; pointer-events: none;
}
.op-env-from { margin: 0; font-size: 14px; color: var(--op-muted); padding-right: 150px; }
.op-env-line { display: flex; align-items: center; gap: 12px; border-bottom: 1px dashed var(--op-line); padding: 6px 0; margin: 0; }
.op-env-to { margin-top: 46px; flex-wrap: wrap; }
.op-env-k { flex: none; font-size: 13px; color: var(--op-muted); min-width: 3.4em; }
.op-env-addr { font-size: 15px; }
.op-code {
  font-family: var(--op-latin); font-size: 32px; font-weight: 700; letter-spacing: .06em; color: var(--op-ink);
  background: none; padding: 0; line-height: 1.2;
}
.op-copy {
  margin-left: auto; min-height: 44px; min-width: 76px; padding: 0 18px; border: 0; border-radius: var(--op-r2);
  background: var(--op-blue); color: #fff; font: inherit; font-size: 15px; font-weight: 700; cursor: pointer;
}
.op-copy:hover { background: #1b3678; }
.op-copy.op-copied { background: var(--op-red); }
.op-env-gain { margin: 14px 0 4px; font-size: 17px; font-weight: 700; line-height: 1.6; }
.op-env-gain sup, .op-cc-gain sup, .op-env-foot sup, .op-cc-foot sup { color: var(--op-red); font-weight: 700; }
.op-env-foot { margin: 0; font-size: 13.5px; line-height: 1.6; color: var(--op-muted); }
.op-env-go { margin: 10px 0 6px; }
.op-env-link, .op-cc-link {
  display: inline-flex; align-items: center; min-height: 48px; padding: 0 22px; border-radius: var(--op-r2);
  background: var(--op-red); color: #fff; font-weight: 700; text-decoration: none;
}
.op-env-link:hover, .op-cc-link:hover { background: #a42a21; color: #fff; }
.op-env-note { margin: 0 0 8px; font-size: 13px; color: var(--op-muted); }

/* 首页正文区 */
.op-home-body { max-width: 760px; margin: 0 auto; padding: 8px 24px 0; }
.op-home-body > h2:first-child { margin-top: 16px; }
.op-home-list { max-width: 760px; margin: 0 auto; padding: 8px 24px 72px; }
.op-home-list h2 { font-size: 24px; margin: 48px 0 18px; }
.op-home-list h2::before { content: ""; display: block; height: 3px; margin-bottom: 22px; background: var(--op-stripe); }
.op-more { margin: 14px 0 0; }
.op-more a { display: inline-flex; align-items: center; min-height: 44px; }

.op-cards { list-style: none; margin: 0; padding: 0; display: grid; gap: 14px; }
.op-card { background: var(--op-card); border: 1px solid var(--op-line); border-radius: var(--op-r); padding: 18px 20px; }
.op-card-t { font-size: 19px; font-weight: 700; line-height: 1.5; color: var(--op-ink); }
.op-card-t:hover { color: var(--op-blue); }
.op-card-d { margin: 8px 0 6px; color: var(--op-muted); font-size: 15px; }
.op-card-m { margin: 0; font-size: 13px; color: var(--op-muted); font-family: var(--op-latin), var(--op-cjk); }

/* 正文排印 */
.op-prose { font-size: 16.5px; }
.op-prose p, .op-prose ul, .op-prose ol { margin: 0 0 1.1em; max-width: 38em; }
.op-prose li { margin: .35em 0; }
.op-prose h2 { font-size: 25px; line-height: 1.4; margin: 56px 0 18px; }
.op-prose h2::before { content: ""; display: block; height: 3px; margin-bottom: 24px; background: var(--op-stripe); }
.op-prose h3 { font-size: 19px; line-height: 1.5; margin: 34px 0 10px; color: var(--op-blue); }
.op-prose strong { color: var(--op-ink); }
.op-prose .op-note { font-size: 14px; color: var(--op-muted); }

.op-shot { margin: 26px 0 30px; }
.op-shot img { display: block; border: 1px solid var(--op-line); border-radius: var(--op-r2); background: #1e2329; }
.op-shot figcaption, .op-cover figcaption {
  margin-top: 10px; font-size: 14px; line-height: 1.65; color: var(--op-muted); padding-left: 12px; border-left: 3px solid var(--op-red); max-width: 38em;
}

.op-tablewrap { overflow-x: auto; margin: 22px 0 28px; border: 1px solid var(--op-line); border-radius: var(--op-r); background: var(--op-card); }
.op-table { border-collapse: collapse; width: 100%; min-width: 560px; font-size: 15px; line-height: 1.65; }
.op-table th, .op-table td { padding: 11px 14px; text-align: left; vertical-align: top; border-bottom: 1px solid var(--op-line); }
.op-table thead th { background: var(--op-soft); font-size: 14px; }
.op-table tbody tr:last-child th, .op-table tbody tr:last-child td { border-bottom: 0; }
.op-table tbody th { font-weight: 700; width: 30%; }
.op-al-center { text-align: center; }
.op-al-right { text-align: right; }

/* 面包屑 */
.op-crumb { display: flex; flex-wrap: wrap; align-items: center; gap: 2px 8px; font-size: 14px; color: var(--op-muted); margin-bottom: 14px; }
.op-crumb a { display: inline-flex; align-items: center; min-height: 44px; color: var(--op-muted); }
.op-crumb a:hover { color: var(--op-blue); }

/* 文章页 */
.op-art-col { max-width: 700px; margin: 0 auto; padding: 24px 24px 72px; }
.op-art-head h1 { margin-bottom: 14px; line-break: strict; }
.op-h1seg { display: inline-block; max-width: 100%; }
.op-art-meta { display: flex; flex-wrap: wrap; gap: 4px 18px; margin: 0 0 24px; font-size: 14px; color: var(--op-muted); }
.op-cover { margin: 0 0 28px; }
.op-cover img { display: block; border-radius: var(--op-r); border: 1px solid var(--op-line); }
.op-toc { background: var(--op-card); border: 1px solid var(--op-line); border-radius: var(--op-r); padding: 4px 20px 6px; margin: 0 0 30px; }
.op-toc summary { cursor: pointer; font-weight: 700; min-height: 44px; display: flex; align-items: center; }
.op-toc-nav ul { list-style: none; margin: 0 0 10px; padding: 0; counter-reset: op-toc; }
.op-toc-nav li { counter-increment: op-toc; display: flex; gap: 12px; align-items: baseline; padding: 2px 0; }
.op-toc-nav li::before { content: counter(op-toc, decimal-leading-zero); font-family: var(--op-latin); color: var(--op-red); font-size: 14px; flex: none; }
.op-toc-nav a { display: inline-block; padding: 6px 0; color: var(--op-ink); text-decoration: none; line-height: 1.55; }
.op-toc-nav a:hover { color: var(--op-blue); text-decoration: underline; }

/* 文内码卡 */
.op-cc { position: relative; margin: 26px 0 34px; background: var(--op-card); border: 1px solid var(--op-line); border-radius: var(--op-r); padding: 26px 22px 18px; overflow: hidden; }
.op-cc::before { content: ""; position: absolute; left: 0; right: 0; top: 0; height: 7px; background: var(--op-stripe); }
.op-cc-h { margin: 0 0 6px; font-size: 14px; color: var(--op-muted); }
.op-cc-row { display: flex; align-items: center; gap: 14px; flex-wrap: wrap; padding: 4px 0 10px; border-bottom: 1px dashed var(--op-line); }
.op-cc-gain { margin: 12px 0 10px; font-size: 17px; font-weight: 700; }
.op-cc-go { margin: 0 0 10px; }
.op-cc-note { margin: 0 0 8px; font-size: 14px; color: var(--op-muted); line-height: 1.7; }
.op-cc-foot { margin: 0; font-size: 13.5px; color: var(--op-muted); line-height: 1.6; }

/* FAQ 与文末 */
.op-faq { margin-top: 56px; }
.op-faq h2 { font-size: 25px; margin: 0 0 8px; }
.op-faq h2::before { content: ""; display: block; height: 3px; margin-bottom: 24px; background: var(--op-stripe); }
.op-qa { border-bottom: 1px dashed var(--op-line); padding: 6px 0 4px; }
.op-qa h3 { font-size: 18px; margin: 16px 0 6px; color: var(--op-ink); }
.op-qa p { margin: 0 0 14px; font-size: 16px; }
.op-art-foot { margin-top: 44px; display: grid; gap: 22px; }
.op-tags { display: flex; flex-wrap: wrap; align-items: center; gap: 8px; }
.op-tags-k { font-size: 14px; color: var(--op-muted); margin-right: 4px; }
.op-tag { display: inline-flex; align-items: center; min-height: 32px; padding: 0 12px; border: 1px solid var(--op-line); border-radius: var(--op-r2); background: var(--op-card); font-size: 14px; color: var(--op-ink); text-decoration: none; }
a.op-tag { min-height: 44px; }
.op-next { background: var(--op-card); border: 1px solid var(--op-line); border-left: 4px solid var(--op-blue); border-radius: var(--op-r); padding: 14px 20px 6px; }
.op-next-k { margin: 0; font-weight: 700; }
.op-next ul { margin: 4px 0 8px; padding-left: 1.2em; }
.op-next a { display: inline-block; padding: 6px 0; }

/* 列表页 / 站务页 */
.op-list-head h1, .op-doc-head h1, .op-find h1, .op-lost h1 { font-size: 40px; }
.op-list-pg { font-size: 18px; color: var(--op-muted); margin-left: 12px; font-weight: 400; }
.op-list-intro p { margin: 0 0 12px; color: var(--op-muted); max-width: 38em; }
.op-list-count { font-size: 14px; color: var(--op-muted); margin: 0 0 18px; }
.op-cards-list { margin-bottom: 24px; }
.op-pager { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 18px; }
.op-pager a, .op-pager span { display: inline-flex; align-items: center; justify-content: center; min-width: 44px; min-height: 44px; padding: 0 12px; border: 1px solid var(--op-line); border-radius: var(--op-r2); background: var(--op-card); text-decoration: none; }
.op-pager span[aria-current] { background: var(--op-ink); color: #fff; border-color: var(--op-ink); }
.op-taglist { list-style: none; padding: 0; display: flex; flex-wrap: wrap; gap: 10px; }
.op-taglist a { display: inline-flex; min-height: 44px; align-items: center; }
.op-term-syn { color: var(--op-muted); font-size: 14px; }
.op-doc-meta { font-size: 14px; color: var(--op-muted); margin: 0 0 8px; }
.op-doc .op-prose h2 { font-size: 22px; margin-top: 40px; }

/* 检索 */
.op-find-form label { display: block; font-size: 14px; color: var(--op-muted); margin-bottom: 6px; }
.op-find-row { display: flex; gap: 10px; }
.op-find-row input {
  flex: 1; min-width: 0; min-height: 48px; padding: 0 14px; font: inherit; font-size: 16px; color: var(--op-ink);
  border: 1px solid #9aa6c2; border-radius: var(--op-r2); background: #fff;
}
.op-find-row button { min-height: 48px; padding: 0 20px; border: 0; border-radius: var(--op-r2); background: var(--op-blue); color: #fff; font: inherit; font-weight: 700; cursor: pointer; }
.op-find-status { font-size: 14px; color: var(--op-muted); margin: 14px 0; }
.op-find-out { list-style: none; padding: 0; margin: 0; display: grid; gap: 12px; }
.op-find-item { background: var(--op-card); border: 1px solid var(--op-line); border-radius: var(--op-r); padding: 14px 18px; }
.op-find-item a { font-weight: 700; display: inline-block; padding: 4px 0; }
.op-find-item p { margin: 4px 0 0; font-size: 14px; color: var(--op-muted); }

/* 404 */
.op-lost-mark { font-family: var(--op-latin); font-size: 64px; color: var(--op-red); margin: 0; line-height: 1; }
.op-lost-go { padding-left: 1.2em; }
.op-lost-go a { display: inline-flex; min-height: 44px; align-items: center; }

/* 页脚 */
.op-foot { background: var(--op-ink); color: #dfe5f1; margin-top: 24px; }
.op-foot::before { content: ""; display: block; height: 4px; background: var(--op-stripe); }
.op-foot-in { max-width: 1120px; margin: 0 auto; padding: 36px 24px 28px; display: grid; grid-template-columns: minmax(0, 1.3fr) minmax(0, 1fr); gap: 20px 48px; }
.op-foot a { color: #fff; }
.op-foot a:hover { color: #ffd2cd; }
.op-brand-foot { color: #fff; }
.op-brand-foot:hover { color: #fff; }
.op-foot-id p { margin: 8px 0 0; font-size: 14px; line-height: 1.75; max-width: 36em; }
.op-foot-nav { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 0 18px; align-content: start; }
.op-foot-nav a { display: inline-flex; align-items: center; min-height: 44px; font-size: 14px; text-decoration: none; border-bottom: 1px solid rgba(255, 255, 255, .12); }
.op-foot-nav a:hover { text-decoration: underline; }
.op-foot-small { grid-column: 1 / -1; display: flex; flex-wrap: wrap; justify-content: space-between; gap: 8px 20px; margin: 4px 0 0; font-size: 13px; color: #b9c3d8; }
.op-feed { display: inline-flex; align-items: center; min-height: 44px; }
.op-foot-year { display: inline-flex; align-items: center; min-height: 44px; font-family: var(--op-latin), var(--op-cjk); }

@media (max-width: 900px) {
  .op-hero { grid-template-columns: minmax(0, 1fr); grid-template-areas: "h" "env" "rec" "lead"; padding-top: 30px; }
  .op-hero .op-env { max-width: 480px; }
}

@media (max-width: 640px) {
  :root { --op-h1: 31px; }
  body { font-size: 16px; }
  .op-top-in { padding: 4px 12px; gap: 4px; }
  .op-logo { width: 104px; height: 26px; }
  .op-nav a { padding: 0 8px; font-size: 15px; }
  .op-wrap, .op-art-col, .op-home-body, .op-home-list { padding-left: 16px; padding-right: 16px; }
  .op-hero { padding: 18px 16px 24px; row-gap: 14px; }
  .op-hero-lead { font-size: 16px; }
  .op-env { padding: 8px; }
  .op-env-in { padding: 14px 14px 12px; }
  .op-stamp { top: 10px; right: 10px; width: 50px; height: 60px; padding: 4px; }
  .op-stamp-face img { width: 30px; height: 30px; }
  .op-postmark { top: 18px; right: 52px; width: 56px; height: 56px; font-size: 8px; }
  .op-env-from { padding-right: 110px; font-size: 13px; }
  .op-env-to { margin-top: 30px; gap: 8px; }
  .op-code { font-size: 27px; }
  .op-copy { min-width: 68px; padding: 0 14px; }
  .op-env-gain { margin-top: 10px; font-size: 16px; }
  .op-rec { padding: 14px 16px 12px; }
  .op-rec-t { font-size: 17px; }
  .op-prose { font-size: 16px; }
  .op-prose h2 { font-size: 21px; margin-top: 44px; }
  .op-prose h3 { font-size: 18px; }
  .op-list-head h1, .op-doc-head h1, .op-find h1, .op-lost h1 { font-size: 28px; }
  .op-foot-in { grid-template-columns: minmax(0, 1fr); padding: 28px 16px 20px; }
  .op-faq h2 { font-size: 21px; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { transition: none !important; animation: none !important; scroll-behavior: auto !important; }
}

@media print {
  .op-top, .op-foot, .op-toc, .op-cc, .op-env { display: none; }
}