:root {
  /* 摘星色系：白底 + 皇家蓝 → 紫 */
  --bg: #ffffff;
  --bg-soft: #f3f7ff;
  --bg-tint: #eaf1ff;
  --bg-hero: linear-gradient(165deg, #e8f2ff 0%, #f5f8ff 42%, #ffffff 78%);
  --panel: #ffffff;
  --line: #dce6f5;
  --border: var(--line);
  --text: #1a2744;
  --text-muted: #5b6b86;
  --text-dim: #8a97ad;
  --accent: #3779f7;
  --accent-2: #2b5aed;
  --accent-purple: #7d6dff;
  --grad: linear-gradient(90deg, #3779f7 0%, #7d6dff 100%);
  --grad-btn: linear-gradient(135deg, #3779f7 0%, #6a6df8 55%, #7d6dff 100%);
  --grad-soft: linear-gradient(135deg, rgba(55, 121, 247, 0.12), rgba(125, 109, 255, 0.1));
  --accent-soft: rgba(55, 121, 247, 0.1);
  --success: #10b981;
  --danger: #ef4444;
  --radius: 10px;
  --radius-sm: 8px;
  --radius-lg: 16px;
  --shadow: 0 12px 36px rgba(43, 90, 237, 0.1);
  --shadow-lg: 0 20px 50px rgba(43, 90, 237, 0.14);
  --container: 1200px;
  --font: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", system-ui, sans-serif;
  --header-h: 72px;
  --section-y: clamp(3.5rem, 6vw, 5.5rem);
  --motion: 0.55s cubic-bezier(0.22, 1, 0.36, 1);
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--font);
  color: var(--text);
  background: var(--bg);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

a {
  color: inherit;
  text-decoration: none;
}

img {
  max-width: 100%;
  display: block;
}

button,
input,
select,
textarea {
  font: inherit;
}

.container {
  width: min(100% - 2.5rem, var(--container));
  margin-inline: auto;
}

.section {
  padding: var(--section-y) 0;
  position: relative;
}

.section-panel,
.section-soft {
  background: var(--bg-soft);
}

.section-head {
  margin-bottom: 2rem;
  max-width: 40rem;
}

.section-head.center {
  margin-inline: auto;
  text-align: center;
}

/* 大标题独占一行，导语在下方全宽平铺 */
.section-head-stack {
  display: flex;
  flex-direction: column;
  align-items: stretch;
  gap: 0.75rem;
  max-width: none;
  margin-bottom: 2rem;
}

.section-head-stack h2 {
  margin: 0;
  line-height: 1.25;
  max-width: none;
}

.section-head-lead {
  margin: 0;
  color: var(--text-muted);
  font-size: 1rem;
  line-height: 1.75;
  max-width: none;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  color: var(--accent);
  font-size: 0.8rem;
  letter-spacing: 0.06em;
  margin-bottom: 0.85rem;
  font-weight: 600;
}

.eyebrow .num {
  color: var(--accent-purple);
}

h1, h2, h3, h4 {
  line-height: 1.25;
  margin: 0 0 0.75rem;
  font-weight: 700;
  letter-spacing: -0.01em;
  color: var(--text);
}

h1 { font-size: clamp(2.1rem, 4.2vw, 3.2rem); }
h2 { font-size: clamp(1.55rem, 2.8vw, 2.15rem); }
h3 { font-size: 1.15rem; font-weight: 600; }

.lead {
  color: var(--text-muted);
  font-size: 1.02rem;
  max-width: 40rem;
  line-height: 1.75;
}

.muted { color: var(--text-muted); }
.dim { color: var(--text-dim); }

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.4rem;
  padding: 0.8rem 1.45rem;
  border-radius: 999px;
  border: none;
  background: var(--grad-btn);
  color: #fff;
  font-weight: 600;
  cursor: pointer;
  box-shadow: 0 8px 20px rgba(55, 121, 247, 0.28);
  transition: transform 0.2s ease, box-shadow 0.2s ease, filter 0.2s ease;
}

.btn:hover {
  filter: brightness(1.05);
  transform: translateY(-1px);
  box-shadow: 0 12px 26px rgba(55, 121, 247, 0.34);
}

.btn-ghost {
  background: #fff;
  color: var(--accent-2);
  border: 1px solid rgba(55, 121, 247, 0.35);
  box-shadow: none;
}

.btn-ghost:hover {
  background: var(--accent-soft);
  filter: none;
  border-color: var(--accent);
}

.btn-line {
  background: #fff;
  color: var(--accent-2);
  border: 1px solid rgba(55, 121, 247, 0.35);
  box-shadow: none;
}

.panel,
.card {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  padding: 1.4rem 1.45rem;
  box-shadow: var(--shadow);
}

.tag {
  display: inline-block;
  padding: 0.2rem 0.65rem;
  border-radius: 999px;
  background: var(--accent-soft);
  color: var(--accent-2);
  font-size: 0.78rem;
  font-weight: 600;
}

.page-hero {
  padding: 3.5rem 0 2.25rem;
  border-bottom: 1px solid var(--line);
  background:
    radial-gradient(ellipse 60% 80% at 90% 0%, rgba(125, 109, 255, 0.14), transparent 55%),
    radial-gradient(ellipse 50% 70% at 10% 20%, rgba(55, 121, 247, 0.12), transparent 50%),
    var(--bg-soft);
}

.breadcrumb {
  color: var(--text-dim);
  font-size: 0.88rem;
  margin-bottom: 1rem;
}

.breadcrumb a:hover { color: var(--accent); }

.reveal {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity var(--motion), transform var(--motion);
}

.reveal.is-in {
  opacity: 1;
  transform: none;
}

.faq-section-title {
  margin: 0 0 1rem;
  font-size: 1.15rem;
}

.faq-section-title--spaced {
  margin-top: 2.5rem;
}

/* GEO 问答页 · 对齐第六版宽版舞台 */
.faq-stage {
  padding: 2.75rem 0 4rem;
  background:
    radial-gradient(800px 260px at 88% -80px, rgba(55, 121, 247, 0.12) 0%, transparent 70%),
    var(--bg-soft);
}

.faq-stage-inner {
  max-width: min(1080px, 100%);
}

.faq-stage .breadcrumb strong {
  color: var(--accent-2);
  font-weight: 600;
}

.faq-kicker {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  color: #c2703d;
  font-size: 0.82rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  margin: 0.25rem 0 0.85rem;
}

.faq-kicker-bar {
  width: 2rem;
  height: 2px;
  background: #c2703d;
  flex-shrink: 0;
}

.faq-title {
  font-size: clamp(1.85rem, 3.2vw, 2.35rem);
  margin: 0 0 1rem;
  letter-spacing: 0.02em;
  line-height: 1.25;
}

.faq-lead-card {
  margin: 0;
  padding: 1.1rem 1.35rem;
  font-size: 0.98rem;
  line-height: 1.9;
  color: var(--text-muted);
  background: #fff;
  border: 1px solid var(--line);
  border-left: 4px solid var(--accent-2);
  border-radius: 12px;
  max-width: none;
}

.faq-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 0.75rem;
  margin: 1rem 0 0;
  font-size: 0.78rem;
  color: var(--text-dim);
}

.faq-meta span {
  padding: 0.25rem 0.65rem;
  border-radius: 6px;
  background: var(--grad-soft);
  border: 1px solid var(--line);
  color: var(--accent-2);
  font-weight: 600;
}

.faq-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
  margin: 1.35rem 0 2rem;
}

.faq-nav a {
  font-size: 0.86rem;
  font-weight: 600;
  color: var(--accent-2);
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 0.45rem 1rem;
  transition: background 0.15s ease, border-color 0.15s ease;
}

.faq-nav a:hover {
  border-color: var(--accent);
  background: var(--grad-soft);
}

.faq-group {
  margin-bottom: 2.5rem;
  scroll-margin-top: calc(var(--header-h) + 1rem);
}

.faq-group-head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 0.7rem 0.9rem;
  margin: 0 0 1.1rem;
  padding-bottom: 0.75rem;
  border-bottom: 2px solid var(--accent-2);
}

.faq-group-num {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 2.1rem;
  padding: 0.2rem 0.55rem;
  border-radius: 8px;
  background: var(--grad-btn);
  color: #fff;
  font-size: 0.8rem;
  font-weight: 800;
}

.faq-group-head h2 {
  margin: 0;
  font-size: 1.28rem;
}

.faq-group-sub {
  margin-left: auto;
  font-size: 0.82rem;
  color: var(--text-dim);
}

.faq-stage .faq-list details.faq-item,
.faq-list details.faq-item {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 0;
  margin: 0 0 0.75rem;
  box-shadow: 0 3px 12px rgba(43, 90, 237, 0.05);
  overflow: hidden;
}

.faq-list details.faq-item[open] {
  border-color: #bcd0f5;
  box-shadow: 0 8px 22px rgba(43, 90, 237, 0.1);
}

.faq-list details.faq-item summary {
  cursor: pointer;
  font-weight: 700;
  font-size: 1rem;
  color: var(--text);
  padding: 1.05rem 3rem 1.05rem 1.35rem;
  list-style: none;
  position: relative;
  line-height: 1.55;
}

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

.faq-list details.faq-item summary::after {
  content: "+";
  position: absolute;
  right: 1.2rem;
  top: 50%;
  transform: translateY(-50%);
  font-size: 1.35rem;
  font-weight: 400;
  color: var(--accent);
  line-height: 1;
}

.faq-list details.faq-item[open] summary {
  color: var(--accent-2);
}

.faq-list details.faq-item[open] summary::after {
  content: "–";
}

.faq-answer {
  padding: 0 1.35rem 1.15rem;
  border-top: 1px dashed var(--line);
}

.faq-answer p {
  color: var(--text-muted);
  margin: 0.85rem 0 0;
  font-size: 0.92rem;
  line-height: 1.9;
}

.faq-answer-lead {
  color: var(--text) !important;
  font-weight: 600;
}

.faq-cite {
  display: inline-block;
  margin: 0.75rem 0 0.25rem;
  padding: 0.2rem 0.65rem;
  border-radius: 5px;
  background: var(--grad-soft);
  color: var(--accent-2);
  font-size: 0.76rem;
  font-weight: 700;
}

.faq-cta {
  margin-top: 0.5rem;
  padding: 1.75rem 1.85rem;
  border-radius: 16px;
  background: var(--grad-btn);
  color: #fff;
  display: flex;
  flex-wrap: wrap;
  gap: 1.25rem 2rem;
  align-items: center;
  justify-content: space-between;
  box-shadow: 0 16px 36px rgba(55, 121, 247, 0.28);
}

.faq-cta-title {
  font-size: 1.2rem;
  font-weight: 800;
  margin-bottom: 0.4rem;
}

.faq-cta-copy p {
  margin: 0;
  font-size: 0.92rem;
  line-height: 1.75;
  color: rgba(255, 255, 255, 0.9);
  max-width: 40rem;
}

.faq-cta-action {
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: 0.45rem;
  flex-shrink: 0;
}

.faq-cta-action .btn {
  background: #fff;
  color: var(--accent-2);
  box-shadow: none;
}

.faq-cta-note {
  font-size: 0.78rem;
  color: rgba(255, 255, 255, 0.85);
}

.faq-compliance {
  margin: 1.5rem 0 0;
  padding: 1.25rem 1.4rem;
  border-radius: 12px;
  border: 1px dashed rgba(194, 112, 61, 0.45);
  background: #fdf8f2;
  color: var(--text-muted);
  font-size: 0.9rem;
  line-height: 1.8;
  text-align: left;
}

.faq-compliance h3 {
  margin: 0 0 0.75rem;
  font-size: 1.05rem;
  color: #9a5326;
}

.faq-compliance p {
  margin: 0 0 0.65rem;
}

.faq-compliance ul {
  margin: 0.25rem 0 0.65rem;
  padding-left: 1.25rem;
}

.faq-compliance li {
  margin: 0.15rem 0;
}

@media (max-width: 640px) {
  .section { padding: 3.25rem 0; }

  .faq-stage {
    padding: 1.75rem 0 3rem;
  }

  .faq-group-sub {
    margin-left: 0;
    width: 100%;
  }

  .faq-cta-action {
    align-items: flex-start;
    width: 100%;
  }

  .faq-list details.faq-item summary {
    padding-right: 2.6rem;
    font-size: 0.95rem;
  }
}