:root {
  --ink: #16191d;
  --ink-2: #4a5158;
  --ink-3: #7d858c;
  --line: #e3e7ec;
  --bg: #ffffff;
  --bg-2: #f6f8fa;
  --brand: #12467b;
  --brand-soft: #e8f0f8;
  --accent: #c8452d;
  --radius: 10px;
}

* { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  color: var(--ink);
  background: var(--bg);
  font-size: 17px;
  line-height: 1.75;
}

.wrap { max-width: 760px; margin: 0 auto; padding: 0 20px; }

a { color: var(--brand); text-decoration: none; }
a:hover { text-decoration: underline; }

.crumb {
  font-size: 13px;
  color: var(--ink-3);
  padding: 18px 0 0;
}
.crumb a { color: var(--ink-3); }
.crumb span { margin: 0 6px; }

h1 {
  font-size: 28px;
  line-height: 1.35;
  font-weight: 600;
  letter-spacing: -0.3px;
  margin: 14px 0 12px;
}

.lede {
  font-size: 16px;
  color: var(--ink-2);
  margin: 0 0 28px;
  padding-left: 14px;
  border-left: 3px solid var(--brand);
}

h2 {
  font-size: 20px;
  font-weight: 600;
  margin: 40px 0 16px;
  letter-spacing: -0.2px;
}

/* 规格卡 */
.spec-card {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  margin-bottom: 16px;
  overflow: hidden;
}

.spec-head {
  background: var(--bg-2);
  padding: 12px 16px;
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 8px;
  border-bottom: 1px solid var(--line);
}

.spec-head .stage { font-weight: 600; font-size: 15px; }

.spec-head .region {
  font-size: 13px;
  color: var(--ink-3);
}

.spec-grid {
  display: grid;
  grid-template-columns: 92px 1fr;
  gap: 0;
}

.spec-grid > div {
  padding: 10px 16px;
  border-bottom: 1px solid var(--line);
  font-size: 15px;
  min-width: 0;
  overflow-wrap: break-word;
}

.spec-grid > div:nth-last-child(-n+2) { border-bottom: none; }

.spec-grid .k {
  color: var(--ink-3);
  font-size: 13px;
  white-space: nowrap;
}

.spec-grid .v { font-weight: 500; }

.spec-grid .v.hero {
  font-size: 20px;
  font-weight: 600;
  letter-spacing: -0.2px;
  color: var(--ink);
}

.spec-src {
  padding: 10px 16px;
  font-size: 12px;
  color: var(--ink-3);
  background: var(--bg-2);
  border-top: 1px solid var(--line);
}
.spec-src a { color: var(--ink-3); text-decoration: underline; }

/* CTA */
.cta {
  margin: 28px 0;
  padding: 22px;
  border-radius: var(--radius);
  background: var(--brand-soft);
  border: 1px solid #cfdff0;
  display: flex;
  align-items: center;
  gap: 24px;
}
.cta-main { flex: 1; min-width: 0; }
.cta h3 { margin: 0 0 6px; font-size: 17px; font-weight: 600; }
.cta p { margin: 0 0 16px; font-size: 14px; color: var(--ink-2); }
.cta p:last-child { margin-bottom: 0; }
.btn {
  display: inline-block;
  background: var(--accent);
  color: #fff;
  font-weight: 600;
  font-size: 16px;
  padding: 12px 26px;
  border-radius: 8px;
}
.btn:hover { text-decoration: none; opacity: .92; }

.cta-qr {
  flex: 0 0 auto;
  width: 132px;
  text-align: center;
}
.cta-qr img {
  display: block;
  width: 132px;
  height: 132px;
  border-radius: 8px;
  background: #fff;
}
.cta-qr span {
  display: block;
  font-size: 12px;
  color: var(--ink-3);
  margin-top: 8px;
  line-height: 1.5;
}
.cta-qr .qr-tip-mobile { display: none; }

/* 易错点 */
ul.pit { list-style: none; padding: 0; margin: 0; }
ul.pit li {
  position: relative;
  padding: 12px 16px 12px 44px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  margin-bottom: 10px;
  font-size: 15px;
}
ul.pit li::before {
  content: "!";
  position: absolute;
  left: 16px;
  top: 13px;
  width: 18px;
  height: 18px;
  line-height: 18px;
  text-align: center;
  border-radius: 50%;
  background: #fdeceb;
  color: var(--accent);
  font-size: 12px;
  font-weight: 700;
}

/* 场景标签 */
ul.plain-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}
ul.plain-list li {
  padding: 7px 14px;
  background: var(--bg-2);
  border-radius: 6px;
  font-size: 14px;
  color: var(--ink-2);
}

/* FAQ */
.faq details {
  border-bottom: 1px solid var(--line);
  padding: 14px 0;
}
.faq summary {
  font-weight: 500;
  cursor: pointer;
  font-size: 16px;
  list-style: none;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: "+"; float: right; color: var(--ink-3); }
.faq details[open] summary::after { content: "−"; }
.faq p { margin: 10px 0 0; font-size: 15px; color: var(--ink-2); }

/* 相关 */
.related {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  padding: 0;
  list-style: none;
  margin: 0;
}
.related a {
  display: block;
  padding: 9px 15px;
  border: 1px solid var(--line);
  border-radius: 20px;
  font-size: 14px;
  color: var(--ink-2);
}
.related a:hover { border-color: var(--brand); color: var(--brand); text-decoration: none; }

/* 表格 */
.table-scroll { overflow-x: auto; margin: 0 0 16px; }
table {
  width: 100%;
  border-collapse: collapse;
  font-size: 14px;
  min-width: 520px;
}
th, td {
  text-align: left;
  padding: 10px 12px;
  border-bottom: 1px solid var(--line);
}
th {
  background: var(--bg-2);
  font-weight: 600;
  font-size: 13px;
  color: var(--ink-2);
  white-space: nowrap;
}
td strong { font-weight: 600; }

.note {
  font-size: 13px;
  color: var(--ink-3);
  background: var(--bg-2);
  padding: 12px 16px;
  border-radius: var(--radius);
  margin: 16px 0;
}

footer {
  margin-top: 56px;
  padding: 24px 0 40px;
  border-top: 1px solid var(--line);
  font-size: 12px;
  color: var(--ink-3);
  line-height: 1.7;
}

@media (max-width: 560px) {
  body { font-size: 16px; }
  h1 { font-size: 23px; }
  h2 { font-size: 18px; }
  .spec-grid { grid-template-columns: 84px 1fr; }
  .spec-grid .v.hero { font-size: 17px; }
  .spec-grid > div { padding: 9px 12px; font-size: 14px; }
  .wrap { padding: 0 16px; }
  .cta { flex-direction: column-reverse; align-items: center; gap: 16px; padding: 20px 18px; }
  .cta-main { width: 100%; text-align: center; }
  .cta-qr { width: auto; }
  .cta-qr img { width: 176px; height: 176px; margin: 0 auto; border-radius: 10px; }
  .cta-qr span { font-size: 13px; margin-top: 10px; }
  .cta-qr .qr-tip-desktop { display: none; }
  .cta-qr .qr-tip-mobile { display: block; }
  .btn { display: block; text-align: center; }
}

/* 首页分组小标题 */
h3.grp {
  font-size: 14px;
  color: var(--ink-3);
  font-weight: 600;
  letter-spacing: .04em;
  margin: 22px 0 10px;
}