:root {
  --ink: #172033;
  --muted: #657086;
  --line: #e3e8f0;
  --paper: #ffffff;
  --soft: #f5f7fb;
  --brand: #3347d8;
  --brand-dark: #2535a8;
  --accent: #ff6b57;
  --success: #167c61;
  --radius: 18px;
  --shadow: 0 16px 44px rgba(30, 42, 80, .09);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font: 16px/1.75 -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  text-rendering: optimizeLegibility;
}
img { max-width: 100%; height: auto; }
a { color: var(--brand); text-decoration: none; }
a:hover { color: var(--brand-dark); }
h1, h2, h3, p { margin-top: 0; }
h1, h2, h3 { line-height: 1.28; letter-spacing: -.025em; }
ul { padding-left: 1.2em; }
.container { width: min(1160px, calc(100% - 40px)); margin-inline: auto; }
.skip-link {
  position: fixed;
  left: 16px;
  top: -80px;
  z-index: 9999;
  padding: 10px 14px;
  color: #fff;
  background: var(--brand);
  border-radius: 8px;
}
.skip-link:focus { top: 12px; }

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255, 255, 255, .96);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(14px);
}
.header-inner {
  min-height: 74px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 28px;
}
.site-brand { min-width: 220px; color: var(--ink); }
.site-brand strong, .site-brand span { display: block; }
.site-brand strong { max-width: 290px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; font-size: 20px; }
.site-brand span { color: var(--muted); font-size: 12px; }
.site-nav { overflow-x: auto; scrollbar-width: none; }
.site-nav::-webkit-scrollbar { display: none; }
.site-nav ul, .site-footer ul {
  list-style: none;
  margin: 0;
  padding: 0;
}
.site-nav ul { display: flex; align-items: center; gap: 24px; white-space: nowrap; }
.site-nav a { color: #394258; font-weight: 650; font-size: 14px; }
.site-nav a:hover { color: var(--brand); }

.hero {
  padding: 92px 0 76px;
  color: #fff;
  background:
    radial-gradient(circle at 80% 20%, rgba(255, 107, 87, .34), transparent 28%),
    linear-gradient(135deg, #1b276d, #3347d8 58%, #5b6ceb);
}
.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.55fr) minmax(280px, .75fr);
  align-items: center;
  gap: 64px;
}
.eyebrow, .section-heading > span, .comparison > div > span {
  display: inline-block;
  margin-bottom: 13px;
  color: #ffdfda;
  font-size: 13px;
  font-weight: 800;
  letter-spacing: .12em;
  text-transform: uppercase;
}
.hero h1 { max-width: 760px; margin-bottom: 22px; font-size: clamp(40px, 6vw, 70px); }
.hero p { max-width: 720px; margin-bottom: 34px; color: rgba(255, 255, 255, .82); font-size: 19px; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; }
.button {
  display: inline-flex;
  min-height: 46px;
  align-items: center;
  justify-content: center;
  padding: 10px 20px;
  border: 1px solid transparent;
  border-radius: 999px;
  font-weight: 750;
}
.button-primary { color: var(--brand-dark); background: #fff; }
.button-primary:hover { color: var(--brand-dark); transform: translateY(-1px); }
.button-secondary { color: #fff; border-color: rgba(255, 255, 255, .46); background: rgba(255, 255, 255, .1); }
.button-secondary:hover { color: #fff; background: rgba(255, 255, 255, .18); }
.hero-note {
  padding: 27px;
  border: 1px solid rgba(255, 255, 255, .25);
  border-radius: var(--radius);
  background: rgba(255, 255, 255, .1);
  box-shadow: 0 20px 60px rgba(9, 17, 63, .25);
}
.hero-note strong { display: block; margin-bottom: 10px; }
.hero-note ul { margin: 0; color: rgba(255, 255, 255, .84); }
.hero-note li + li { margin-top: 7px; }

.topic-nav {
  display: flex;
  gap: 10px;
  margin-top: -24px;
  padding: 14px;
  overflow-x: auto;
  border: 1px solid var(--line);
  border-radius: 14px;
  background: #fff;
  box-shadow: var(--shadow);
  white-space: nowrap;
}
.topic-nav a {
  padding: 7px 13px;
  color: #4d576d;
  border-radius: 999px;
  background: var(--soft);
  font-size: 13px;
  font-weight: 700;
}
.topic-nav .is-current { color: #fff; background: var(--brand); }

.section { padding-top: 82px; padding-bottom: 82px; scroll-margin-top: 84px; }
.section-tint { background: var(--soft); }
.section-dark { color: #fff; background: #151d34; }
.section-heading { max-width: 760px; margin: 0 auto 34px; text-align: center; }
.section-heading-left { max-width: none; margin-inline: 0; text-align: left; }
.section-heading > span { color: var(--brand); }
.section-heading h2 { margin-bottom: 10px; font-size: clamp(29px, 4vw, 44px); }
.prose-card {
  max-width: 880px;
  margin: 0 auto;
  padding: 34px 38px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--paper);
  box-shadow: var(--shadow);
}
.prose-card p { color: #3f485c; font-size: 17px; }
.prose-card p:last-child { margin-bottom: 0; }

.card-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 18px; }
.info-card {
  padding: 28px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #fff;
}
.info-card b { display: block; margin-bottom: 26px; color: var(--accent); font-size: 13px; }
.info-card h3 { font-size: 20px; }
.info-card p { margin-bottom: 0; color: var(--muted); font-size: 14px; }

.steps { max-width: 900px; margin: 0 auto; display: grid; gap: 14px; }
.steps article {
  display: grid;
  grid-template-columns: 52px 1fr;
  gap: 20px;
  padding: 24px;
  border: 1px solid var(--line);
  border-radius: 14px;
}
.steps article > strong {
  width: 52px;
  height: 52px;
  display: grid;
  place-items: center;
  color: #fff;
  border-radius: 50%;
  background: var(--brand);
}
.steps h3 { margin-bottom: 6px; }
.steps p { margin-bottom: 0; color: var(--muted); }

.comparison { display: grid; grid-template-columns: 1fr 1fr; align-items: center; gap: 64px; }
.comparison h2 { font-size: clamp(30px, 4vw, 46px); }
.comparison p { color: rgba(255, 255, 255, .72); }
.comparison dl { margin: 0; display: grid; gap: 10px; }
.comparison dl > div {
  display: grid;
  grid-template-columns: 110px 1fr;
  gap: 18px;
  padding: 15px 17px;
  border: 1px solid rgba(255, 255, 255, .13);
  border-radius: 11px;
  background: rgba(255, 255, 255, .05);
}
.comparison dt { font-weight: 800; }
.comparison dd { margin: 0; color: rgba(255, 255, 255, .67); }

.archive-hero {
  padding: 70px 0 64px;
  color: #fff;
  background: linear-gradient(135deg, #202c72, #4255df);
}
.archive-hero h1 { margin: 20px 0 14px; font-size: clamp(36px, 5vw, 58px); }
.archive-hero p { max-width: 760px; margin-bottom: 0; color: rgba(255, 255, 255, .77); font-size: 17px; }
.breadcrumbs { display: flex; flex-wrap: wrap; align-items: center; gap: 8px; color: var(--muted); font-size: 13px; }
.archive-hero .breadcrumbs, .archive-hero .breadcrumbs a { color: rgba(255, 255, 255, .7); }

.post-list {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 22px;
}
.post-card {
  min-width: 0;
  overflow: hidden;
  display: grid;
  grid-template-columns: 190px minmax(0, 1fr);
  border: 1px solid var(--line);
  border-radius: 16px;
  background: #fff;
  transition: transform .2s ease, box-shadow .2s ease;
}
.post-card:hover { transform: translateY(-3px); box-shadow: var(--shadow); }
.post-card-media { min-height: 100%; background: #e8ebf3; }
.post-card-media img { width: 100%; height: 100%; display: block; object-fit: cover; }
.post-card-body { min-width: 0; padding: 22px; }
.post-card-meta { display: flex; align-items: center; gap: 12px; margin-bottom: 10px; color: #8991a3; font-size: 12px; }
.post-card-meta a { color: var(--brand); font-weight: 750; }
.post-card h3 { margin-bottom: 9px; font-size: 19px; }
.post-card h3 a { color: var(--ink); }
.post-card p { display: -webkit-box; overflow: hidden; margin-bottom: 14px; color: var(--muted); font-size: 13px; -webkit-line-clamp: 3; -webkit-box-orient: vertical; }
.text-link { font-size: 13px; font-weight: 750; }
.empty-state { padding: 32px; color: var(--muted); border: 1px dashed #cbd2df; border-radius: 14px; text-align: center; }

.faq-list { max-width: 900px; margin: 0 auto; display: grid; gap: 12px; }
.faq-list details { border: 1px solid var(--line); border-radius: 13px; background: #fff; }
.faq-list summary { padding: 19px 22px; cursor: pointer; font-weight: 780; }
.faq-list p { padding: 0 22px 20px; margin-bottom: 0; color: var(--muted); }

.article-shell { max-width: 900px; padding-top: 56px; padding-bottom: 46px; }
.article-header { padding: 30px 0 36px; border-bottom: 1px solid var(--line); }
.article-kicker { display: inline-block; margin-bottom: 14px; font-size: 13px; font-weight: 800; }
.article-header h1 { margin-bottom: 18px; font-size: clamp(36px, 5vw, 56px); overflow-wrap: anywhere; }
.article-deck { max-width: 780px; color: var(--muted); font-size: 18px; }
.article-meta { display: flex; flex-wrap: wrap; gap: 10px 22px; color: #848da0; font-size: 13px; }
.article-content { padding: 38px 0; color: #303a4f; font-size: 17px; line-height: 1.9; overflow-wrap: anywhere; }
.article-content h2 { margin: 2.2em 0 .8em; font-size: 30px; }
.article-content h3 { margin: 1.8em 0 .7em; font-size: 23px; }
.article-content p, .article-content ul, .article-content ol { margin-bottom: 1.3em; }
.article-content img { display: block; margin: 28px auto; border-radius: 12px; }
.article-content blockquote { margin: 26px 0; padding: 18px 22px; color: #4c566d; border-left: 4px solid var(--brand); background: var(--soft); }
.article-content pre { max-width: 100%; padding: 18px; overflow: auto; border-radius: 10px; background: #101728; color: #edf1ff; }
.table-scroll { max-width: 100%; overflow-x: auto; }
.article-content table { width: 100%; border-collapse: collapse; }
.article-content td, .article-content th { padding: 10px 12px; border: 1px solid var(--line); }
.article-footer { padding-top: 26px; border-top: 1px solid var(--line); }
.tag-links { display: flex; flex-wrap: wrap; align-items: center; gap: 8px; }
.tag-links a { padding: 5px 10px; border-radius: 999px; background: var(--soft); font-size: 12px; }
.post-navigation { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; margin-top: 26px; }
.post-navigation a { min-width: 0; padding: 17px; border: 1px solid var(--line); border-radius: 12px; }
.post-navigation small, .post-navigation span { display: block; }
.post-navigation small { color: var(--muted); }
.post-navigation span { color: var(--ink); font-weight: 700; overflow-wrap: anywhere; }
.related-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 16px; }
.related-grid article { padding: 22px; border: 1px solid var(--line); border-radius: 14px; }
.related-grid strong, .related-grid span { display: block; }
.related-grid strong { margin-bottom: 8px; color: var(--ink); }
.related-grid span { color: var(--muted); font-size: 13px; }

.pagination { display: flex; flex-wrap: wrap; justify-content: center; gap: 8px; margin-top: 34px; }
.pagination a, .pagination span { min-width: 40px; height: 40px; display: grid; place-items: center; padding: 0 12px; border: 1px solid var(--line); border-radius: 9px; }
.pagination .is-current { color: #fff; border-color: var(--brand); background: var(--brand); }

.site-footer { padding: 58px 0 22px; color: #c7cede; background: #11182a; }
.footer-grid { display: grid; grid-template-columns: 1.3fr 1fr .7fr; gap: 52px; }
.footer-brand { display: inline-block; margin-bottom: 10px; color: #fff; font-size: 21px; font-weight: 800; }
.site-footer p { max-width: 470px; color: #929db3; font-size: 13px; }
.site-footer strong { display: block; margin-bottom: 13px; color: #fff; }
.site-footer li + li { margin-top: 8px; }
.site-footer a { color: #b8c1d4; font-size: 13px; }
.site-footer nav ul { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 7px 14px; }
.footer-bottom { display: flex; justify-content: space-between; gap: 20px; margin-top: 42px; padding-top: 20px; color: #737f97; border-top: 1px solid rgba(255, 255, 255, .09); font-size: 12px; }

@media (max-width: 980px) {
  .header-inner { align-items: flex-start; flex-direction: column; gap: 10px; padding: 14px 0; }
  .site-nav { width: 100%; }
  .hero-grid, .comparison { grid-template-columns: 1fr; gap: 34px; }
  .card-grid { grid-template-columns: repeat(2, 1fr); }
  .post-list { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .footer-grid > div:first-child { grid-column: 1 / -1; }
}

@media (max-width: 640px) {
  .container { width: min(100% - 28px, 1160px); }
  .site-brand strong { max-width: calc(100vw - 28px); }
  .site-nav ul { gap: 18px; }
  .hero { padding: 64px 0 52px; }
  .hero h1 { font-size: 39px; }
  .hero p { font-size: 16px; }
  .hero-note { padding: 21px; }
  .section { padding-top: 62px; padding-bottom: 62px; }
  .prose-card { padding: 25px; }
  .card-grid { grid-template-columns: 1fr; }
  .comparison dl > div { grid-template-columns: 1fr; gap: 3px; }
  .post-card { grid-template-columns: 1fr; }
  .post-card-media { height: 190px; }
  .article-shell { padding-top: 34px; }
  .article-header { padding-top: 22px; }
  .article-header h1 { font-size: 37px; }
  .article-content { font-size: 16px; }
  .post-navigation, .related-grid, .footer-grid { grid-template-columns: 1fr; }
  .footer-grid > div:first-child { grid-column: auto; }
  .footer-bottom { align-items: flex-start; flex-direction: column; }
}

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