:root {
  --bg: #f6f4ee;
  --surface: rgba(255, 255, 255, 0.78);
  --surface-strong: #fffdf8;
  --text: #1f241f;
  --muted: #5d665d;
  --line: rgba(31, 36, 31, 0.12);
  --brand: #1f7a5c;
  --brand-soft: #dff2e8;
  --accent: #c96b3b;
  --shadow: 0 18px 50px rgba(31, 36, 31, 0.08);
  --radius: 22px;
  --max: 1120px;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  color: var(--text);
  background:
    radial-gradient(circle at top left, rgba(201, 107, 59, 0.12), transparent 28%),
    radial-gradient(circle at top right, rgba(31, 122, 92, 0.14), transparent 30%),
    linear-gradient(180deg, #fbfaf6, var(--bg));
  line-height: 1.6;
}
a { color: var(--brand); text-decoration: none; }
a:hover { text-decoration: underline; }
.shell { width: min(calc(100% - 32px), var(--max)); margin: 0 auto; }
.topbar {
  position: sticky; top: 0; z-index: 20; backdrop-filter: blur(16px);
  background: rgba(246, 244, 238, 0.84); border-bottom: 1px solid var(--line);
}
.nav {
  display: flex; align-items: center; justify-content: space-between; gap: 20px; padding: 16px 0;
}
.brand { display: flex; flex-direction: column; gap: 2px; }
.brand strong { font-size: 1rem; letter-spacing: 0.02em; }
.brand span { color: var(--muted); font-size: 0.85rem; }
.nav-links { display: flex; gap: 18px; flex-wrap: wrap; justify-content: flex-end; }
.hero { padding: 72px 0 30px; display: grid; grid-template-columns: 1.15fr 0.85fr; gap: 28px; }
.hero-card, .panel, .guide-card, .cluster-card, .note-card, .article-card {
  background: var(--surface); border: 1px solid var(--line); box-shadow: var(--shadow); border-radius: var(--radius);
}
.hero-copy { padding: 34px; }
.eyebrow {
  display: inline-flex; align-items: center; gap: 8px; padding: 8px 12px; border-radius: 999px;
  background: var(--brand-soft); color: var(--brand); font-size: 0.84rem; font-weight: 700;
  letter-spacing: 0.04em; text-transform: uppercase;
}
h1, h2, h3 { line-height: 1.15; margin: 0 0 14px; }
h1 { font-size: clamp(2.2rem, 4vw, 4.2rem); letter-spacing: -0.04em; }
h2 { font-size: clamp(1.6rem, 2vw, 2.4rem); letter-spacing: -0.03em; }
.lede, .summary { color: var(--muted); font-size: 1.04rem; }
.hero-actions, .cta-row { display: flex; gap: 14px; flex-wrap: wrap; margin-top: 24px; }
.button {
  display: inline-flex; align-items: center; justify-content: center; padding: 12px 18px; border-radius: 999px;
  border: 1px solid transparent; font-weight: 700;
}
.button.primary { background: var(--brand); color: white; }
.button.secondary { background: var(--surface-strong); color: var(--text); border-color: var(--line); }
.stats { display: grid; gap: 14px; padding: 24px; }
.stat { padding: 18px; border-radius: 18px; background: var(--surface-strong); border: 1px solid var(--line); }
.stat strong { display: block; font-size: 1.8rem; margin-bottom: 4px; }
.stat span { display: block; max-width: 24ch; color: var(--muted); }
.section { padding: 30px 0; }
.section-head { display: flex; justify-content: space-between; gap: 20px; align-items: end; margin-bottom: 18px; }
.grid-3, .grid-2 { display: grid; gap: 18px; }
.grid-3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid-2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.cluster-card, .guide-card, .note-card, .article-card, .panel { padding: 22px; }
.chip {
  display: inline-block; margin-bottom: 10px; padding: 6px 10px; border-radius: 999px;
  background: #f0ece1; color: var(--accent); font-size: 0.78rem; font-weight: 700;
}
.cluster-card ul, .panel ul, .article-card ul { margin: 12px 0 0; padding-left: 18px; }
.footer { padding: 32px 0 60px; color: var(--muted); }
.article-layout { display: grid; grid-template-columns: minmax(0, 1fr) 290px; gap: 24px; padding: 46px 0 60px; }
.article-main, .article-side {
  background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); box-shadow: var(--shadow);
}
.article-main { padding: 32px; }
.article-main h1 { font-size: clamp(2rem, 3vw, 3rem); }
.article-main h2 { margin-top: 28px; }
.article-side { padding: 22px; align-self: start; position: sticky; top: 90px; }
.breadcrumb { font-size: 0.9rem; color: var(--muted); margin-bottom: 16px; }
.trust-meta {
  margin: 16px 0 20px;
  padding: 16px 18px;
  border: 1px solid var(--line);
  border-radius: 18px;
  background: rgba(223, 242, 232, 0.42);
}
.trust-meta p {
  margin: 0;
  color: var(--muted);
}
.trust-meta p + p {
  margin-top: 6px;
}
.guide-next {
  margin-top: 34px;
  padding-top: 22px;
  border-top: 1px solid var(--line);
}
.guide-next h2 {
  margin-top: 0;
}
.guide-next-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 16px;
}
.list-clean { list-style: none; padding: 0; margin: 0; }
.list-clean li + li { margin-top: 10px; }
.contact-form {
  margin-top: 28px;
  display: grid;
  gap: 16px;
}
.form-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
}
.contact-form label {
  display: grid;
  gap: 8px;
  font-weight: 600;
}
.contact-form input,
.contact-form select,
.contact-form textarea {
  width: 100%;
  border: 1px solid var(--line);
  background: var(--surface-strong);
  color: var(--text);
  border-radius: 16px;
  padding: 12px 14px;
  font: inherit;
}
.contact-form textarea {
  resize: vertical;
}
.form-actions {
  display: flex;
  gap: 14px;
  flex-wrap: wrap;
  align-items: center;
}
.form-note,
.form-status {
  color: var(--muted);
  margin: 0;
}
.hp-field {
  position: absolute;
  left: -9999px;
  width: 1px;
  height: 1px;
  opacity: 0;
  pointer-events: none;
}
@media (max-width: 920px) {
  .hero, .article-layout, .grid-3, .grid-2 { grid-template-columns: 1fr; }
  .article-side { position: static; }
  .section-head, .nav { align-items: start; flex-direction: column; }
  .hero { padding-top: 32px; }
  .hero-copy, .stats { padding: 22px; }
  .stat { padding: 16px; }
  .stat strong { font-size: 1.65rem; }
  .stat span { max-width: none; font-size: 0.98rem; }
  .form-grid { grid-template-columns: 1fr; }
}