:root {
  color-scheme: dark;
  --brand-bg: #08111f;
  --brand-panel: #101d31;
  --brand-panel-hover: #142844;
  --brand-text: #eef5ff;
  --brand-muted: #9db0c9;
  --brand-line: rgba(157, 176, 201, .18);
  --brand-accent: #4da3ff;
  --brand-accent-strong: #86c5ff;
}

* { box-sizing: border-box; }
html { background: var(--brand-bg); }
body { margin: 0; min-height: 100vh; color: var(--brand-text); background: var(--brand-bg); font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif; line-height: 1.7; }
a { color: inherit; text-decoration: none; }
.brand-nav { border-bottom: 1px solid var(--brand-line); background: rgba(8, 17, 31, .96); }
.brand-nav-inner { width: min(1120px, calc(100% - 40px)); min-height: 72px; margin: 0 auto; display: flex; align-items: center; justify-content: space-between; gap: 24px; }
.brand-logo { color: var(--brand-text); font-size: 22px; font-weight: 700; letter-spacing: .04em; }
.brand-logo::before { content: "⚡"; margin-right: 8px; color: var(--brand-accent); }
.brand-nav nav { display: flex; align-items: center; gap: 26px; color: var(--brand-muted); font-size: 14px; }
.brand-nav nav a { padding: 23px 0; border-bottom: 2px solid transparent; }
.brand-nav nav a:hover, .brand-nav nav a.active { color: var(--brand-text); border-bottom-color: var(--brand-accent); }
.brand-main { width: min(1120px, calc(100% - 40px)); margin: 0 auto; }
.brand-hero { max-width: 760px; padding: 88px 0 62px; }
.eyebrow { margin: 0 0 14px; color: var(--brand-accent-strong); font-size: 12px; font-weight: 700; letter-spacing: .12em; }
.brand-hero h1 { margin: 0 0 16px; font-size: clamp(34px, 5vw, 58px); line-height: 1.15; letter-spacing: .01em; }
.brand-hero > p:last-child { max-width: 650px; margin: 0; color: var(--brand-muted); font-size: 18px; }
.article-list { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 18px; padding: 0 0 90px; }
.article-card { min-height: 230px; padding: 28px; border: 1px solid var(--brand-line); border-radius: 8px; background: var(--brand-panel); transition: border-color .2s ease, background .2s ease, transform .2s ease; }
.article-card:hover { border-color: rgba(77, 163, 255, .62); background: var(--brand-panel-hover); transform: translateY(-2px); }
.article-meta { display: flex; gap: 14px; color: var(--brand-muted); font-size: 13px; }
.article-meta span + span { padding-left: 14px; border-left: 1px solid var(--brand-line); }
.article-card h2 { margin: 14px 0 10px; font-size: 22px; line-height: 1.4; }
.article-card h2 a:hover { color: var(--brand-accent-strong); }
.article-card p { display: -webkit-box; overflow: hidden; margin: 0; color: var(--brand-muted); -webkit-box-orient: vertical; -webkit-line-clamp: 3; }
.read-more { display: inline-block; margin-top: 18px; color: var(--brand-accent-strong); font-size: 14px; font-weight: 600; }
.read-more span { margin-left: 6px; }
.empty-state { grid-column: 1 / -1; padding: 70px 20px; text-align: center; color: var(--brand-muted); border: 1px dashed var(--brand-line); }
.article-main { width: min(880px, calc(100% - 40px)); margin: 0 auto; padding: 38px 0 90px; }
.breadcrumbs { display: flex; flex-wrap: wrap; gap: 9px; margin-bottom: 38px; color: var(--brand-muted); font-size: 13px; }
.breadcrumbs a:hover { color: var(--brand-accent-strong); }
.article-header { padding-bottom: 34px; border-bottom: 1px solid var(--brand-line); }
.article-header h1 { max-width: 820px; margin: 0 0 18px; font-size: clamp(30px, 5vw, 48px); line-height: 1.25; }
.article-summary { margin: 0; color: var(--brand-muted); font-size: 18px; }
.article-date { margin-top: 14px; color: #7287a3; font-size: 13px; }
.article-cover { display: block; width: 100%; height: auto; margin-top: 28px; border-radius: 8px; object-fit: contain; }
.article-body { padding-top: 38px; color: #d9e5f4; font-size: 17px; }
.article-body h1, .article-body h2, .article-body h3 { margin: 34px 0 12px; color: var(--brand-text); line-height: 1.35; }
.article-body h1 { font-size: 32px; } .article-body h2 { font-size: 26px; } .article-body h3 { font-size: 21px; }
.article-body p { margin: 0 0 20px; text-indent: 2em; line-height: 2; }
.article-body h1 + p, .article-body h2 + p, .article-body h3 + p, .article-body li p { text-indent: 0; }
.article-body ul { margin: 0 0 20px; padding-left: 24px; }
.article-body li { margin: 7px 0; }
.article-body strong { color: #fff; }
.article-body code { padding: 2px 6px; border-radius: 4px; background: rgba(255,255,255,.08); color: var(--brand-accent-strong); font-size: .9em; }
.article-body img { display: block; max-width: 100%; height: auto; margin: 24px auto; border-radius: 6px; }
.article-body .article-figure { margin: 30px 0 34px; text-align: center; }
.article-body .article-figure img { width: 100%; height: auto; max-height: none; margin: 0 auto 8px; object-fit: contain; }
.article-body .article-figure figcaption { color: var(--brand-muted); font-size: 13px; line-height: 1.6; text-indent: 0; }
.article-body a { color: var(--brand-accent-strong); text-decoration: underline; text-underline-offset: 3px; }
.brand-footer { width: min(1120px, calc(100% - 40px)); margin: 0 auto; padding: 24px 0 34px; display: flex; justify-content: space-between; gap: 20px; border-top: 1px solid var(--brand-line); color: var(--brand-muted); font-size: 13px; }
.brand-footer a { color: var(--brand-text); font-weight: 700; }
.collection-breadcrumbs { margin: 28px 0 0; }
.collection-hero { max-width: 880px; padding: 40px 0 32px; }
.collection-hero h1 { font-size: clamp(30px, 4vw, 46px); line-height: 1.3; }
.collection-hero > p:last-child { max-width: 800px; }
.topic-nav { display: flex; flex-wrap: wrap; gap: 10px; margin: 8px 0 30px; }
.topic-nav a { border: 1px solid var(--brand-line); border-radius: 6px; padding: 8px 13px; font-size: 14px; }
.topic-nav a:hover, .topic-nav a[aria-current] { background: var(--brand-panel-hover); border-color: var(--brand-accent); }
.topic-nav span { margin-left: 5px; color: var(--brand-muted); }
.topic-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 16px; margin: 0 0 46px; }
.topic-card { display: block; padding: 24px; border: 1px solid var(--brand-line); border-radius: 8px; background: var(--brand-panel); }
.topic-card:hover { border-color: var(--brand-accent); }
.topic-card h2 { margin: 0 0 10px; font-size: 20px; line-height: 1.4; }
.topic-card p { margin: 0 0 16px; color: var(--brand-muted); font-size: 14px; }
.topic-card > span { color: var(--brand-accent-strong); font-size: 14px; }
.topic-guide { padding: 22px 26px; border-left: 3px solid var(--brand-accent); background: var(--brand-panel); margin-bottom: 28px; }
.topic-guide h2 { font-size: 19px; margin: 0 0 10px; }
.topic-guide ul { margin: 0; padding-left: 22px; color: var(--brand-muted); }
.collection-heading { display: flex; gap: 14px; align-items: baseline; margin-bottom: 18px; }
.collection-heading h2 { font-size: 23px; margin: 0; }
.collection-heading > span { color: var(--brand-muted); font-size: 14px; }
.article-card h3 { margin: 14px 0 10px; font-size: 22px; line-height: 1.45; }
.article-card h3 a:hover, .article-meta a:hover { color: var(--brand-accent-strong); }
.article-meta { flex-wrap: wrap; }
.pagination { display: flex; flex-wrap: wrap; justify-content: center; align-items: center; gap: 20px; padding: 0 0 60px; }
.pagination a { color: var(--brand-accent-strong); border: 1px solid var(--brand-line); border-radius: 6px; padding: 10px 16px; }
.article-toc { margin-top: 28px; padding: 20px 24px; border: 1px solid var(--brand-line); border-radius: 8px; background: var(--brand-panel); }
.article-toc h2 { font-size: 18px; margin: 0 0 10px; }
.article-toc ol { padding-left: 22px; margin: 0; }
.article-toc li { padding: 3px 0; }
.article-toc .toc-level-3 { margin-left: 20px; font-size: 14px; }
.article-toc a, .article-next a { color: var(--brand-accent-strong); }
.article-toc a:hover, .article-next a:hover { text-decoration: underline; text-underline-offset: 3px; }
.article-body h2[id], .article-body h3[id] { scroll-margin-top: 24px; }
.article-next, .article-cta { margin-top: 40px; padding: 26px; border: 1px solid var(--brand-line); border-radius: 8px; }
.article-next h2, .article-cta h2 { margin: 0 0 12px; font-size: 22px; }
.article-next p, .article-cta p { color: var(--brand-muted); }
.article-next ul { padding-left: 22px; margin-bottom: 0; }
.article-next li { margin: 10px 0; }
.article-cta { background: var(--brand-panel); }
.article-cta > a { display: inline-block; margin: 8px 18px 0 0; color: var(--brand-accent-strong); }
body { overflow-wrap: anywhere; }
a:focus-visible { outline: 2px solid var(--brand-accent); outline-offset: 4px; }
@media (max-width: 960px) { .topic-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); } }
@media (max-width: 680px) {
  .brand-nav-inner { width: min(100% - 28px, 1120px); min-height: 62px; }
  .brand-nav nav { gap: 14px; font-size: 13px; }
  .brand-nav nav a { padding: 18px 0; }
  .brand-main, .article-main, .brand-footer { width: min(100% - 28px, 1120px); }
  .brand-hero { padding: 58px 0 42px; }
  .brand-hero > p:last-child { font-size: 16px; }
  .article-list { grid-template-columns: 1fr; padding-bottom: 58px; }
  .article-card { padding: 22px; }
  .article-main { padding-top: 24px; }
  .article-body { font-size: 16px; }
  .topic-grid { grid-template-columns: 1fr; }
  .collection-hero { padding: 28px 0; }
  .topic-card, .topic-guide, .article-toc, .article-next, .article-cta { padding: 20px; }
  .brand-footer { flex-direction: column; gap: 5px; }
}