:root {
  --ink: #171717;
  --muted: #6f6a62;
  --paper: #fbfaf8;
  --soft: #f4f0e9;
  --line: rgba(23, 23, 23, 0.12);
  --gold: #9b7a4d;
  --radius: 8px;
  --max: 1160px;
}

* { box-sizing: border-box; }
html {
  scroll-behavior: smooth;
  overflow-x: hidden;
}
body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Display", "PingFang SC", "Microsoft YaHei", Arial, sans-serif;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

a { color: inherit; text-decoration: none; }
.container { width: min(var(--max), calc(100% - 48px)); margin: 0 auto; }

.site-header {
  position: fixed;
  inset: 0 0 auto;
  z-index: 20;
  height: 58px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.42);
  background: rgba(250, 248, 244, 0.76);
  backdrop-filter: saturate(180%) blur(18px);
}

.nav {
  height: 58px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand { font-size: 19px; font-weight: 700; white-space: nowrap; }
.brand small { margin-left: 8px; color: var(--muted); font-size: 12px; font-weight: 500; }
.nav-links { display: flex; gap: 28px; color: rgba(23, 23, 23, 0.72); font-size: 13px; }
.nav-cta {
  padding: 8px 16px;
  border-radius: 999px;
  background: var(--ink);
  color: #fff;
  font-size: 13px;
  line-height: 1;
  white-space: nowrap;
}

.hero {
  padding: 150px 0 76px;
  background:
    radial-gradient(circle at 82% 12%, rgba(155, 122, 77, 0.16), transparent 30%),
    linear-gradient(180deg, #fbfaf8 0%, #f2eee7 100%);
}

.eyebrow {
  margin: 0 0 18px;
  color: var(--gold);
  font-size: 13px;
  font-weight: 650;
}

h1 {
  margin: 0;
  max-width: 820px;
  font-size: clamp(44px, 7vw, 86px);
  line-height: 1.06;
  letter-spacing: 0;
}

.hero p.lead {
  max-width: 680px;
  margin: 28px 0 0;
  color: var(--muted);
  font-size: 19px;
  line-height: 1.75;
}

.section { padding: 92px 0; }
.section.soft { background: var(--soft); }
.section-head {
  display: grid;
  grid-template-columns: 1fr minmax(260px, 430px);
  gap: 40px;
  align-items: end;
  margin-bottom: 42px;
}

h2 {
  margin: 0;
  font-size: clamp(32px, 4vw, 54px);
  line-height: 1.12;
}

.lead { margin: 0; color: var(--muted); font-size: 16px; line-height: 1.75; }

.category-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 14px;
}

.category-card,
.article-card,
.placeholder-card {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #fff;
  overflow: hidden;
}

.category-card {
  min-height: 270px;
  padding: 24px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  transition: transform 180ms ease, box-shadow 180ms ease;
}

.category-card:hover,
.article-card:hover {
  transform: translateY(-3px);
  box-shadow: 0 18px 48px rgba(38, 32, 25, 0.11);
}

.category-card span,
.article-card span,
.placeholder-card span {
  color: rgba(23, 23, 23, 0.46);
  font-size: 13px;
  font-weight: 650;
}

.category-card h3,
.article-card h3,
.placeholder-card h3 {
  margin: 0 0 10px;
  font-size: 23px;
  line-height: 1.25;
}

.category-card p,
.article-card p,
.placeholder-card p {
  margin: 0;
  color: var(--muted);
  font-size: 14px;
  line-height: 1.65;
}

.article-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 14px;
}

.guide-list {
  margin-top: 64px;
}

.guide-entry {
  margin-bottom: 36px;
}

.guide-entry h2 {
  max-width: 720px;
  margin-bottom: 16px;
  font-size: clamp(30px, 4vw, 46px);
}

.guide-entry .lead {
  max-width: 700px;
  margin-bottom: 24px;
}

.guide-cards .article-card {
  min-height: 240px;
}

.guide-cards .article-card div {
  display: block;
}

.guide-cards .article-card h3 {
  min-height: 2.5em;
  margin: 0 0 14px;
}

.topic-strip {
  max-width: 820px;
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
  margin-bottom: 22px;
}

.topic-strip button {
  padding: 10px 14px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: #fff;
  color: var(--muted);
  font-size: 13px;
  font-weight: 650;
  font-family: inherit;
  cursor: pointer;
}

.topic-strip button.active {
  color: #fff;
  background: var(--ink);
  border-color: var(--ink);
}

.topic-strip button:hover {
  color: var(--ink);
  border-color: rgba(23, 23, 23, 0.34);
}

.topic-strip button.active:hover {
  color: #fff;
  border-color: var(--ink);
}

.article-card[hidden] {
  display: none;
}

.article-card {
  min-height: 200px;
  padding: 22px;
  display: flex;
  flex-direction: column;
  justify-content: flex-start;
  gap: 68px;
  transition: transform 180ms ease, box-shadow 180ms ease;
}

.article-card h3 { margin-top: 0; }

.layout {
  display: grid;
  grid-template-columns: 260px 1fr;
  gap: 32px;
  align-items: start;
}

.side-nav {
  position: sticky;
  top: 90px;
  display: grid;
  gap: 8px;
}

.side-nav a {
  padding: 13px 14px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  color: var(--muted);
  background: #fff;
  font-size: 14px;
}

.side-nav a.active {
  color: var(--ink);
  border-color: rgba(23, 23, 23, 0.24);
}

.placeholder-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 14px;
}

.placeholder-card {
  min-height: 190px;
  padding: 24px;
}

.placeholder-card p + p {
  margin-top: 10px;
}

.placeholder-note {
  margin-top: 24px;
  padding: 22px;
  border-radius: var(--radius);
  background: #151515;
  color: rgba(255,255,255,0.72);
  font-size: 15px;
  line-height: 1.7;
}

.content-stack {
  display: grid;
  gap: 22px;
}

.faq-section {
  display: grid;
  gap: 12px;
}

.faq-section h2 {
  margin: 0 0 8px;
  font-size: clamp(26px, 3vw, 40px);
}

.faq-item {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #fff;
  overflow: hidden;
}

.faq-item summary {
  cursor: pointer;
  padding: 20px 22px;
  font-size: 18px;
  font-weight: 700;
  list-style: none;
}

.faq-item summary::-webkit-details-marker { display: none; }

.faq-answer {
  padding: 0 22px 22px;
  color: var(--muted);
  font-size: 15px;
  line-height: 1.78;
}

.faq-answer p,
.article-body p,
.article-body ul,
.article-body ol {
  margin: 0 0 16px;
}

.article-body {
  max-width: 820px;
  padding: 36px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #fff;
  color: var(--muted);
  font-size: 17px;
  line-height: 1.86;
}

.article-body h2 {
  margin: 0 0 22px;
  color: var(--ink);
  font-size: clamp(30px, 4vw, 50px);
  line-height: 1.16;
}

.article-body h3 {
  margin: 32px 0 12px;
  color: var(--ink);
  font-size: 23px;
  line-height: 1.35;
}

.article-body strong {
  color: var(--ink);
}

.article-body ul,
.article-body ol {
  padding-left: 1.3em;
}

.article-body li {
  margin: 7px 0;
}

.article-takeaways {
  margin: 0 0 30px;
  padding: 22px;
  border: 1px solid rgba(155, 122, 77, 0.26);
  border-radius: var(--radius);
  background: #fbf7ef;
}

.article-takeaways h3 {
  margin: 0 0 12px;
  color: var(--ink);
  font-size: 18px;
}

.article-takeaways ul {
  margin: 0;
  padding-left: 1.15em;
}

.article-takeaways li {
  margin: 6px 0;
}

.guide-kicker {
  margin: 0 0 16px;
  color: var(--gold);
  font-size: 14px;
  font-weight: 700;
}

.answer-panel {
  padding: 26px;
  border: 1px solid rgba(155, 122, 77, 0.28);
  border-radius: var(--radius);
  background: #fbf7ef;
}

.answer-panel p {
  margin: 0;
  color: var(--ink);
  font-size: 22px;
  line-height: 1.62;
  font-weight: 700;
}

.compare-table {
  width: 100%;
  margin: 18px 0 26px;
  border-collapse: collapse;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  font-size: 15px;
}

.compare-table th,
.compare-table td {
  padding: 16px;
  border-bottom: 1px solid var(--line);
  text-align: left;
  vertical-align: top;
}

.compare-table th {
  color: var(--ink);
  background: #f4f0e9;
}

.compare-table tr:last-child th,
.compare-table tr:last-child td {
  border-bottom: 0;
}

.article-nav {
  max-width: 820px;
  margin-left: 292px;
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  gap: 12px;
  align-items: stretch;
}

.article-nav-section {
  padding: 0 0 92px;
}

.article-nav a,
.article-nav span {
  min-height: 86px;
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #fff;
}

.article-nav span {
  opacity: 0;
}

.article-nav strong {
  display: block;
  margin-bottom: 8px;
  color: rgba(23, 23, 23, 0.44);
  font-size: 12px;
}

.article-nav b {
  display: block;
  color: var(--ink);
  font-size: 16px;
  line-height: 1.4;
}

.article-nav .back-link {
  min-width: 150px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--ink);
  font-weight: 700;
}

.article-nav .next-link { text-align: right; }

footer {
  padding: 34px 0;
  background: #151515;
  color: rgba(255,255,255,0.48);
  font-size: 13px;
}

.footer-row { display: flex; justify-content: space-between; gap: 20px; flex-wrap: wrap; }
.footer-links { display: flex; gap: 18px; flex-wrap: wrap; }
.footer-links a { color: rgba(255,255,255,0.64); }

@media (max-width: 980px) {
  .section-head,
  .layout { grid-template-columns: 1fr; }
  .category-grid,
  .article-grid { grid-template-columns: repeat(2, 1fr); }
  .side-nav { position: static; grid-template-columns: repeat(auto-fit, minmax(120px, 1fr)); }
  .article-nav { margin-left: 0; }
}

@media (max-width: 720px) {
  .container { width: min(100% - 32px, var(--max)); }
  .brand small,
  .nav-links { display: none; }
  .hero { padding: 112px 0 58px; }
  .section { padding: 56px 0; }
  .section-head {
    gap: 22px;
    margin-bottom: 30px;
  }
  h1 { font-size: clamp(38px, 10vw, 48px); }
  h2 { font-size: clamp(30px, 8vw, 40px); }
  .category-grid,
  .article-grid,
  .placeholder-grid,
  .side-nav { grid-template-columns: 1fr; }
  .category-card {
    min-height: 210px;
    padding: 22px;
  }
  .article-card {
    min-height: 170px;
    gap: 36px;
  }
  .guide-list { margin-top: 46px; }
  .article-body { padding: 24px; }
  .article-nav { grid-template-columns: 1fr; }
  .article-nav span { display: none; }
  .article-nav .next-link { text-align: left; }
}