:root {
  --ink: #172033;
  --ink-2: #344159;
  --muted: #667085;
  --paper: #f5f7fb;
  --card: #ffffff;
  --line: #e4e8f0;
  --line-strong: #d6dce8;
  --brand: #2463eb;
  --brand-dark: #1748b5;
  --navy: #10233f;
  --green: #168765;
  --blue-soft: #edf3ff;
  --green-soft: #eaf7f1;
  --amber-soft: #fff7e6;
  --max: 1180px;
  --article: 790px;
  --shadow-sm: 0 2px 10px rgba(16, 35, 63, .05);
  --shadow-md: 0 16px 44px rgba(16, 35, 63, .09);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 96px; }
body {
  margin: 0;
  overflow-x: hidden;
  color: var(--ink);
  background: var(--paper);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  font-size: 16px;
  line-height: 1.72;
  -webkit-font-smoothing: antialiased;
}
a { color: var(--brand); text-decoration-thickness: 1px; text-underline-offset: 4px; }
a:hover { color: var(--brand-dark); }
img { display: block; max-width: 100%; height: auto; }
.wrap { width: min(var(--max), calc(100% - 48px)); margin-inline: auto; }
.skip { position: absolute; left: -9999px; }
.skip:focus { left: 18px; top: 14px; z-index: 30; padding: 10px 14px; background: white; border-radius: 8px; box-shadow: var(--shadow-md); }

/* Header */
.site-head {
  position: sticky;
  top: 0;
  z-index: 20;
  background: rgba(255, 255, 255, .9);
  border-bottom: 1px solid rgba(214, 220, 232, .85);
  backdrop-filter: blur(16px) saturate(150%);
}
.head-inner { min-height: 76px; display: flex; align-items: center; justify-content: space-between; gap: 28px; }
.brand { display: inline-flex; align-items: center; gap: 11px; color: var(--navy); text-decoration: none; font-size: 17px; font-weight: 800; letter-spacing: -.02em; white-space: nowrap; }
.brand-on-dark { color: white; }
.brand-mark {
  width: 36px;
  height: 36px;
  display: grid;
  place-items: center;
  color: white;
  border-radius: 11px;
  background: linear-gradient(145deg, #3478ff, #1852c9);
  box-shadow: 0 8px 20px rgba(36, 99, 235, .24);
  font-size: 15px;
}
nav { display: flex; align-items: center; gap: 5px; font-size: 14px; font-weight: 650; }
nav a { padding: 8px 11px; color: var(--ink-2); border-radius: 8px; text-decoration: none; transition: color .18s, background .18s; }
nav a:hover { color: var(--brand); background: var(--blue-soft); }
.menu { display: none; border: 1px solid var(--line-strong); background: var(--card); color: var(--ink); border-radius: 9px; padding: 7px 11px; font: inherit; }

/* Type */
h1, h2, h3 { color: var(--navy); line-height: 1.24; letter-spacing: -.028em; }
h1 { margin: 0 0 20px; font-size: clamp(38px, 5vw, 62px); font-weight: 820; }
h2 { margin: 0 0 16px; font-size: clamp(27px, 3vw, 38px); font-weight: 780; }
h3 { margin: 0 0 10px; font-size: 20px; font-weight: 750; letter-spacing: -.018em; }
p { margin: 0 0 18px; }
.lede { max-width: 760px; margin-bottom: 0; color: var(--ink-2); font-size: clamp(17px, 1.6vw, 20px); line-height: 1.75; }
.eyebrow { margin: 0 0 12px; color: var(--brand); font-size: 12px; font-weight: 800; letter-spacing: .14em; text-transform: uppercase; }
.small { color: var(--muted); font-size: 13px; }
.tag { display: inline-flex; align-items: center; min-height: 25px; padding: 2px 9px; color: var(--green); background: var(--green-soft); border-radius: 999px; font-size: 12px; font-weight: 750; }

/* Homepage hero */
.hero {
  position: relative;
  overflow: hidden;
  padding: 92px 0 72px;
  background:
    radial-gradient(circle at 92% 16%, rgba(36, 99, 235, .14), transparent 26%),
    radial-gradient(circle at 78% 86%, rgba(22, 135, 101, .10), transparent 24%),
    linear-gradient(180deg, #fbfcff 0%, #f1f5fd 100%);
  border-bottom: 1px solid var(--line);
}
.hero::after { content: ""; position: absolute; width: 340px; height: 340px; right: -180px; top: -180px; border: 1px solid rgba(36,99,235,.18); border-radius: 50%; box-shadow: 0 0 0 46px rgba(36,99,235,.035), 0 0 0 92px rgba(36,99,235,.025); }
.hero-grid { position: relative; z-index: 1; display: grid; grid-template-columns: minmax(0, 1.35fr) minmax(300px, .65fr); gap: 72px; align-items: center; }
.hero-grid > *, .reviewer-grid > * { min-width: 0; }
.hero h1 { max-width: 800px; }
.actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 30px; }
.button { display: inline-flex; align-items: center; justify-content: center; min-height: 46px; padding: 0 19px; color: white; background: var(--brand); border: 1px solid var(--brand); border-radius: 10px; text-decoration: none; font-size: 14px; font-weight: 750; box-shadow: 0 9px 22px rgba(36,99,235,.18); transition: transform .18s, box-shadow .18s, background .18s; }
.button:hover { color: white; background: var(--brand-dark); transform: translateY(-1px); box-shadow: 0 12px 28px rgba(36,99,235,.24); }
.button.secondary { color: var(--ink); background: rgba(255,255,255,.65); border-color: var(--line-strong); box-shadow: none; }
.button.secondary:hover { color: var(--brand); background: white; border-color: #b8c7e9; }
.hero-card { color: #edf4ff; background: linear-gradient(155deg, #152b4c, #0e1e35); border: 1px solid rgba(255,255,255,.08); border-radius: 18px; padding: 30px; box-shadow: 0 24px 64px rgba(16,35,63,.20); }
.hero-card .tag { color: #0f5f49; background: #d9f5e9; }
.hero-card strong { color: #7ee0bd; }
.hero-card ol { margin: 19px 0 0; padding-left: 22px; }
.hero-card li { margin: 12px 0; color: #d6dfec; }

.trustbar { background: white; border-bottom: 1px solid var(--line); }
.trustgrid { display: grid; grid-template-columns: repeat(4, 1fr); }
.trustitem { position: relative; padding: 20px 16px; color: var(--muted); text-align: center; font-size: 12px; }
.trustitem + .trustitem::before { content: ""; position: absolute; left: 0; top: 20%; bottom: 20%; width: 1px; background: var(--line); }
.trustitem b { display: block; margin-bottom: 2px; color: var(--navy); font-size: 15px; }

/* Sections and cards */
main > section { padding: 76px 0; }
main > section + section { border-top: 1px solid rgba(228,232,240,.72); }
main > section:first-child > .wrap > h1 { max-width: 860px; font-size: clamp(36px, 4.3vw, 54px); }
.section-head { display: flex; justify-content: space-between; align-items: end; gap: 48px; margin-bottom: 30px; }
.section-head > div { max-width: 650px; }
.section-head p:last-child { max-width: 540px; margin: 0 0 4px; color: var(--muted); }
.grid-3 { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 20px; }
.deals-grid { margin-top: 24px; }
.card { position: relative; padding: 24px; background: rgba(255,255,255,.94); border: 1px solid var(--line); border-radius: 14px; box-shadow: var(--shadow-sm); transition: transform .18s, border-color .18s, box-shadow .18s; }
.card:hover { transform: translateY(-2px); border-color: #cbd6eb; box-shadow: var(--shadow-md); }
.card .tag { margin-bottom: 15px; }
.card h3 { min-height: 2.5em; }
.card p { color: var(--muted); }
.card p:last-of-type { margin-bottom: 17px; }
.card > a:not(.button) { font-size: 14px; font-weight: 700; text-decoration: none; }
.card-link { font-weight: 700; }

/* Guide hub */
.content-hub > .lede { margin-bottom: 58px; }
.content-hub > h2 { margin-top: 64px; margin-bottom: 22px; padding-top: 6px; font-size: 28px; }
.content-hub > h2:first-of-type { margin-top: 0; }
.content-hub .grid-3 + h2 { margin-top: 66px; }

/* Tables and callouts */
.table-wrap { overflow-x: auto; margin: 22px 0 30px; background: white; border: 1px solid var(--line); border-radius: 13px; box-shadow: var(--shadow-sm); }
table { width: 100%; min-width: 720px; border-collapse: collapse; }
th, td { padding: 15px 17px; text-align: left; vertical-align: top; border-bottom: 1px solid var(--line); }
th { color: var(--ink-2); background: #f1f5fb; font-size: 12px; font-weight: 750; letter-spacing: .04em; }
td { font-size: 14px; }
tr:last-child td { border-bottom: 0; }
.score { color: var(--green); font-weight: 800; }
.notice { margin: 24px 0; padding: 17px 19px; color: #5d4312; background: var(--amber-soft); border: 1px solid #f1ddb0; border-radius: 11px; }
.answer { margin: 26px 0 38px; padding: 24px 26px; color: #eaf1fb; background: linear-gradient(145deg, #142a49, #0f213b); border-radius: 13px; font-size: 17px; line-height: 1.75; box-shadow: 0 14px 36px rgba(16,35,63,.13); }
.answer strong { color: #78dbb8; }

/* Article pages */
.article-wrap { padding-top: 2px; }
.article-layout { display: grid; grid-template-columns: minmax(0, var(--article)) 260px; justify-content: center; gap: 42px; align-items: start; }
.article { min-width: 0; background: white; border: 1px solid var(--line); border-radius: 16px; padding: clamp(30px, 5vw, 54px); box-shadow: var(--shadow-sm); }
.article h1 { max-width: 730px; margin-bottom: 18px; font-size: clamp(34px, 4vw, 50px); line-height: 1.26; }
.article h2 { margin: 52px 0 18px; font-size: 27px; }
.article h3 { margin: 30px 0 12px; font-size: 20px; }
.article p, .article li { color: var(--ink-2); }
.article ul, .article ol { padding-left: 24px; }
.article li { margin: 7px 0; }
.article-meta { margin-bottom: 28px; padding-bottom: 22px; color: var(--muted) !important; border-bottom: 1px solid var(--line); font-size: 13px; }
.evidence { margin: -10px 0 24px; padding: 12px 14px; color: #36536f !important; background: #f3f8fc; border-left: 3px solid #7aa6c7; border-radius: 0 8px 8px 0; font-size: 13px; }
.byline-card { display: flex; gap: 14px; align-items: center; margin: 0 0 28px; padding: 16px 18px; background: #fbfcff; border: 1px solid var(--line); border-radius: 12px; }
.byline-avatar, .author-avatar { flex: 0 0 auto; display: grid; place-items: center; color: white; background: linear-gradient(145deg, #3478ff, #1852c9); font-weight: 850; box-shadow: 0 7px 18px rgba(36,99,235,.18); }
.byline-avatar { width: 42px; height: 42px; border-radius: 12px; font-size: 17px; }
.byline-card b { color: var(--navy); font-size: 14px; }
.byline-card p { margin: 2px 0 0; color: var(--muted); font-size: 12px; line-height: 1.55; }
.byline-card a { color: inherit; text-decoration: none; }
.toc { min-width: 0; position: sticky; top: 98px; padding: 21px; background: rgba(255,255,255,.95); border: 1px solid var(--line); border-radius: 13px; box-shadow: var(--shadow-sm); font-size: 13px; }
.toc strong { display: block; margin-bottom: 10px; color: var(--navy); font-size: 14px; }
.toc a { display: block; padding: 6px 0; color: var(--muted); text-decoration: none; }
.toc a:hover { color: var(--brand); }
.pros-cons { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.pros, .cons { padding: 19px; border: 1px solid var(--line); border-radius: 12px; }
.pros { background: var(--green-soft); }
.cons { background: #fff1ef; }
.faq { margin-top: 48px; }
.faq details { border-top: 1px solid var(--line); padding: 16px 2px; }
.faq details:last-child { border-bottom: 1px solid var(--line); }
.faq summary { cursor: pointer; color: var(--navy); font-weight: 700; }
.faq details p { margin: 12px 0 2px; }

/* Editorial depth and topic hubs */
.breadcrumb { display: flex; flex-wrap: wrap; gap: 7px; margin-bottom: 28px; color: var(--muted); font-size: 12px; }
.breadcrumb a { color: var(--muted); text-decoration: none; }
.breadcrumb a:hover { color: var(--brand); }
.action-list { padding-left: 22px; }
.action-list li { margin: 12px 0; padding-left: 5px; }
.command { margin: 24px 0 32px; overflow: hidden; background: #0c1b30; border: 1px solid #1d3553; border-radius: 12px; }
.command code { display: block; overflow-x: auto; padding: 20px 22px; color: #dceaff; font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace; font-size: 13px; line-height: 1.75; white-space: pre; }
.command p { margin: 0; padding: 13px 20px; color: #aebfd4; background: rgba(255,255,255,.045); border-top: 1px solid rgba(255,255,255,.08); font-size: 12px; }
.source-box { margin: 34px 0; padding: 22px 24px; background: #f4f7fc; border: 1px solid var(--line); border-radius: 12px; }
.source-box > b { display: block; margin-bottom: 8px; color: var(--navy); }
.source-box p { margin-bottom: 12px; font-size: 14px; }
.source-box ul { margin: 0; padding-left: 20px; }
.source-box li { margin: 4px 0; font-size: 13px; }
.related { margin-top: 52px; }
.related-list { display: grid; gap: 10px; }
.related-list a { display: grid; gap: 3px; padding: 15px 17px; color: var(--navy); background: #f7f9fd; border: 1px solid var(--line); border-radius: 10px; text-decoration: none; }
.related-list a:hover { background: var(--blue-soft); border-color: #cbd6eb; }
.related-list span { color: var(--green); font-size: 11px; font-weight: 750; }
.related-list b { font-size: 14px; }
.standalone { max-width: 880px; margin-inline: auto; }
.article-offer { margin: 24px 0 8px; padding: 20px; background: #f7faff; border: 1px solid #c7d5f6; border-radius: 14px; }
.article-offer b { display: block; margin: 10px 0 4px; color: var(--navy); font-size: 18px; }
.article-offer p { margin: 0; color: var(--muted); }
.article-offer-actions { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 14px; }
.article-offer .small { margin-top: 10px; }
.button.compact { min-height: 36px; padding-inline: 12px; font-size: 12px; white-space: nowrap; }
.provider-section { background: white; }

.reviewer-section { background: #edf3ff; }
.reviewer-grid { display: grid; grid-template-columns: 1.12fr .88fr; gap: 54px; align-items: center; }
.evidence-key { display: grid; gap: 12px; }
.evidence-key > div { position: relative; padding: 17px 18px 15px 48px; background: white; border: 1px solid #d7e1f3; border-radius: 12px; box-shadow: var(--shadow-sm); }
.evidence-key b { color: var(--navy); font-size: 14px; }
.evidence-key p { margin: 3px 0 0; color: var(--muted); font-size: 12px; line-height: 1.55; }
.evidence-dot { position: absolute; left: 18px; top: 21px; width: 14px; height: 14px; border-radius: 50%; box-shadow: 0 0 0 4px rgba(36,99,235,.08); }
.evidence-dot.verified { background: #6682ad; }
.evidence-dot.tested { background: var(--brand); }
.evidence-dot.longterm { background: var(--green); }
.author-profile { display: grid; grid-template-columns: 86px 1fr; gap: 24px; align-items: start; margin: 30px 0 36px; padding: 24px; background: #f7faff; border: 1px solid #d6e1f5; border-radius: 14px; }
.author-avatar { width: 76px; height: 76px; border-radius: 22px; font-size: 30px; }
.author-profile h2 { margin: 2px 0 8px; font-size: 24px; }
.author-profile p { margin-bottom: 0; }

.hub-intro { padding: 82px 0 56px; background: linear-gradient(180deg, #fbfcff, #f2f6fd); }
.hub-intro h1 { max-width: 1080px !important; font-size: clamp(36px, 3.7vw, 48px) !important; }
.hub-intro .lede { max-width: 850px; }
.hub-intro .answer { max-width: 1080px; margin-top: 34px; margin-bottom: 0; }
.hub-process { background: white; }
.step-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 18px; margin: 28px 0 0; padding: 0; list-style: none; counter-reset: step; }
.step-grid li { position: relative; min-height: 170px; padding: 23px; background: #f7f9fd; border: 1px solid var(--line); border-radius: 13px; }
.step-grid span { display: grid; width: 32px; height: 32px; margin-bottom: 18px; place-items: center; color: white; background: var(--brand); border-radius: 9px; font-size: 13px; font-weight: 800; }
.step-grid p { margin: 0; color: var(--ink-2); font-size: 14px; }
.topic-section .section-head { margin-bottom: 24px; }
.topic-section .section-head p { max-width: 720px; margin: 8px 0 0; color: var(--muted); }
.hub-cta { display: flex; align-items: center; justify-content: space-between; gap: 32px; margin-bottom: 56px; padding: 28px 30px; color: white; background: linear-gradient(145deg, #142a49, #0f213b); border-radius: 14px; box-shadow: var(--shadow-md); }
.hub-cta b { display: block; margin-bottom: 4px; font-size: 19px; }
.hub-cta p { margin: 0; color: #cbd7e6; }
.hub-faq { max-width: 880px; }

/* Footer */
.footer { margin-top: 44px; padding: 54px 0; color: #d7e1ef; background: #0d1e35; }
.footer-grid { display: grid; grid-template-columns: 1.45fr 1fr 1fr; gap: 52px; }
.footer .brand { color: white; }
.footer p { color: #9fb0c5; }
.footer a { color: #d7e1ef; }
.footer-links { display: grid; align-content: start; gap: 8px; }
.footer-links b { margin-bottom: 6px; color: white; }
.footer-legal { max-width: var(--max); margin: 28px auto 0; padding: 18px 24px 0; color: #91a4bc !important; border-top: 1px solid rgba(255,255,255,.10); font-size: 12px; }

@media (max-width: 920px) {
  .hero-grid, .article-layout, .footer-grid, .reviewer-grid { grid-template-columns: 1fr; }
  .hero-grid { gap: 38px; }
  .hero-card { max-width: 620px; }
  .article-layout { max-width: 820px; margin-inline: auto; }
  .toc { position: static; order: -1; }
  .menu { display: block; }
  nav { display: none; position: absolute; inset: 76px 24px auto; padding: 13px; flex-direction: column; align-items: stretch; background: white; border: 1px solid var(--line); border-radius: 12px; box-shadow: var(--shadow-md); }
  nav.open { display: flex; }
  nav a { padding: 9px 11px; }
  .step-grid { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 740px) {
  .wrap { width: min(100% - 32px, var(--max)); }
  .hero { padding: 66px 0 54px; }
  .grid-3 { grid-template-columns: 1fr; }
  .card h3 { min-height: 0; }
  .trustgrid { grid-template-columns: 1fr 1fr; }
  .trustitem:nth-child(3)::before { display: none; }
  .section-head { display: block; }
  .section-head p:last-child { margin-top: 10px; }
  main > section { padding: 58px 0; }
  .content-hub > .lede { margin-bottom: 42px; }
  .content-hub > h2 { margin-top: 50px; }
  .article { padding: 30px 24px; }
  .pros-cons { grid-template-columns: 1fr; }
  .hub-intro { padding: 62px 0 44px; }
  .hub-cta { display: block; }
  .hub-cta .button { margin-top: 18px; }
}

@media (max-width: 480px) {
  .wrap { width: min(100% - 24px, var(--max)); }
  .head-inner { min-height: 68px; }
  nav { inset: 68px 12px auto; }
  .hero { padding-top: 54px; }
  .hero h1 { font-size: 37px; }
  .hero-card { max-width: 100%; padding: 23px; }
  .trustitem { padding: 17px 8px; }
  main > section:first-child > .wrap > h1 { font-size: 36px; }
  .article-wrap { width: 100%; }
  .article { border-inline: 0; border-radius: 0; padding-inline: 20px; }
  .article h1 { font-size: 34px; }
  .article h2 { margin-top: 44px; font-size: 25px; }
  .answer { padding: 21px; font-size: 16px; }
  .author-profile { grid-template-columns: 56px 1fr; gap: 16px; padding: 19px; }
  .author-avatar { width: 52px; height: 52px; border-radius: 15px; font-size: 22px; }
  .step-grid { grid-template-columns: 1fr; }
  .step-grid li { min-height: 0; }
}