/* ============ 基础 ============ */
:root {
  --primary: #2563eb;
  --primary-dark: #1d4ed8;
  --text: #1e293b;
  --text-light: #64748b;
  --bg: #ffffff;
  --bg-alt: #f1f5f9;
  --border: #e2e8f0;
  --radius: 12px;
}
* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  font-family: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.7;
  font-size: 16px;
}
a { color: var(--primary); text-decoration: none; }
a:hover { text-decoration: underline; }
img { max-width: 100%; }
.container { max-width: 1120px; margin: 0 auto; padding: 0 24px; }
.small { font-size: 13px; color: var(--text-light); }

/* ============ 按钮 ============ */
.btn {
  display: inline-block; padding: 12px 28px; border-radius: 8px;
  font-size: 15px; font-weight: 500; border: 1px solid transparent;
  cursor: pointer; transition: all .2s; text-align: center;
}
.btn:hover { text-decoration: none; }
.btn-primary { background: var(--primary); color: #fff; }
.btn-primary:hover { background: var(--primary-dark); }
.btn-outline { border-color: var(--primary); color: var(--primary); }
.btn-outline:hover { background: rgba(37,99,235,.06); }
.btn-light { background: #fff; color: var(--primary); }
.btn-light:hover { background: #eff6ff; }
.btn-sm { padding: 8px 18px; font-size: 14px; }
.btn-block { width: 100%; }

/* ============ 头部导航 ============ */
.site-header {
  position: sticky; top: 0; z-index: 100;
  background: rgba(255,255,255,.92); backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--border);
}
.header-inner { display: flex; align-items: center; justify-content: space-between; height: 68px; gap: 24px; }
.logo { display: flex; flex-direction: column; line-height: 1.2; }
.logo:hover { text-decoration: none; }
.logo-mark { font-size: 20px; font-weight: 700; color: var(--text); letter-spacing: 1px; }
.logo-sub { font-size: 10px; color: var(--text-light); letter-spacing: 3px; }
.nav { display: flex; gap: 28px; }
.nav a { color: var(--text); font-size: 15px; font-weight: 500; }
.nav a:hover, .nav a.active { color: var(--primary); text-decoration: none; }

/* ============ Hero ============ */
.hero {
  background: linear-gradient(135deg, #eff6ff 0%, #f8fafc 55%, #eef2ff 100%);
  padding: 96px 0 72px;
}
.hero-badge {
  display: inline-block; padding: 6px 16px; border-radius: 999px;
  background: #dbeafe; color: var(--primary-dark);
  font-size: 13px; font-weight: 600; margin-bottom: 20px;
}
.hero h1 { font-size: 44px; line-height: 1.25; letter-spacing: 1px; }
.hero-desc { max-width: 640px; margin: 20px 0 32px; color: var(--text-light); font-size: 17px; }
.hero-actions { display: flex; gap: 16px; flex-wrap: wrap; }
.hero-stats {
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px;
  margin-top: 56px; max-width: 760px;
}
.stat { background: #fff; border: 1px solid var(--border); border-radius: var(--radius); padding: 18px 20px; }
.stat strong { display: block; font-size: 20px; color: var(--primary); }
.stat span { font-size: 13px; color: var(--text-light); }

/* ============ 内页 Hero ============ */
.page-hero { background: linear-gradient(135deg, #eff6ff, #f8fafc); padding: 64px 0; }
.page-hero h1 { font-size: 34px; }
.page-hero p { color: var(--text-light); margin-top: 8px; }

/* ============ 区块 ============ */
.section { padding: 72px 0; }
.section-alt { background: var(--bg-alt); }
.section-title { font-size: 30px; text-align: center; }
.section-desc { text-align: center; color: var(--text-light); margin: 10px 0 44px; }

.grid { display: grid; gap: 24px; }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }
.grid-2 { grid-template-columns: repeat(2, 1fr); }

/* ============ 卡片 ============ */
.card {
  background: #fff; border: 1px solid var(--border); border-radius: var(--radius);
  padding: 28px; transition: transform .2s, box-shadow .2s;
}
.card:hover { transform: translateY(-4px); box-shadow: 0 10px 28px rgba(15,23,42,.08); }
.card-icon { font-size: 30px; margin-bottom: 12px; }
.card h3 { font-size: 18px; margin-bottom: 10px; }
.card p { font-size: 14px; color: var(--text-light); }

/* ============ 步骤 ============ */
.step {
  background: #fff; border: 1px solid var(--border); border-radius: var(--radius);
  padding: 26px 22px; text-align: center;
}
.step-num {
  display: inline-block; width: 44px; height: 44px; line-height: 44px;
  border-radius: 50%; background: var(--primary); color: #fff;
  font-weight: 700; margin-bottom: 14px;
}
.step h3 { font-size: 17px; margin-bottom: 8px; }
.step p { font-size: 13px; color: var(--text-light); }

/* ============ 优势 ============ */
.feature {
  background: #fff; border: 1px solid var(--border); border-radius: var(--radius);
  padding: 26px 28px;
}
.feature h3 { font-size: 17px; margin-bottom: 8px; color: var(--primary-dark); }
.feature p { font-size: 14px; color: var(--text-light); }

/* ============ 服务列表页 ============ */
.service-item {
  background: #fff; border: 1px solid var(--border); border-radius: var(--radius);
  padding: 32px 36px; margin-bottom: 20px;
}
.service-item h2 { font-size: 21px; margin-bottom: 12px; color: var(--primary-dark); }
.service-item p { color: var(--text-light); margin-bottom: 8px; }
.service-item ul { padding-left: 20px; }
.service-item li { font-size: 14.5px; color: var(--text); margin: 4px 0; }

/* ============ 关于页 ============ */
.about-grid { display: grid; grid-template-columns: 1.6fr 1fr; gap: 36px; align-items: start; }
.about-main h2 { font-size: 22px; margin: 28px 0 12px; color: var(--primary-dark); }
.about-main h2:first-child { margin-top: 0; }
.about-main p { color: var(--text-light); margin-bottom: 12px; }
.about-list { list-style: none; }
.about-list li { padding: 8px 0; border-bottom: 1px dashed var(--border); font-size: 15px; }
.info-card {
  background: #fff; border: 1px solid var(--border); border-radius: var(--radius);
  padding: 24px; margin-bottom: 20px;
}
.info-card h3 { font-size: 16px; margin-bottom: 14px; color: var(--primary-dark); }
.info-card dl { display: grid; grid-template-columns: auto 1fr; gap: 6px 14px; font-size: 13.5px; }
.info-card dt { color: var(--text-light); white-space: nowrap; }
.info-card dd { color: var(--text); word-break: break-all; }

/* ============ 联系页 ============ */
.contact-grid { display: grid; grid-template-columns: 1fr 1.2fr; gap: 40px; align-items: start; }
.contact-info h2, .contact-form-wrap h2 { font-size: 22px; margin-bottom: 18px; color: var(--primary-dark); }
.contact-item { border-left: 3px solid var(--primary); padding: 4px 0 4px 16px; margin-bottom: 22px; }
.contact-item h3 { font-size: 16px; margin-bottom: 4px; }
.contact-item p { font-size: 14px; color: var(--text-light); }
.contact-form {
  background: #fff; border: 1px solid var(--border); border-radius: var(--radius); padding: 26px;
}
.contact-form label { display: block; font-size: 14px; font-weight: 500; margin-bottom: 14px; }
.contact-form input, .contact-form select, .contact-form textarea {
  width: 100%; margin-top: 6px; padding: 10px 12px;
  border: 1px solid var(--border); border-radius: 8px; font-size: 14px;
  font-family: inherit; background: #f8fafc;
}
.contact-form input:focus, .contact-form select:focus, .contact-form textarea:focus {
  outline: none; border-color: var(--primary); background: #fff;
}
.form-tip { margin-top: 12px; font-size: 14px; color: #16a34a; min-height: 20px; }

/* ============ CTA ============ */
.cta {
  background: linear-gradient(120deg, var(--primary-dark), var(--primary));
  color: #fff; padding: 64px 0; text-align: center;
}
.cta h2 { font-size: 28px; margin-bottom: 10px; }
.cta p { opacity: .9; margin-bottom: 26px; }

/* ============ 法律条款页 ============ */
.legal { max-width: 860px; }
.legal h2 { font-size: 20px; margin: 30px 0 12px; color: var(--primary-dark); }
.legal h2:first-of-type { margin-top: 0; }
.legal p, .legal li { font-size: 15px; color: var(--text-light); margin-bottom: 8px; }
.legal ul { padding-left: 22px; }

/* ============ 页脚 ============ */
.site-footer { background: #0f172a; color: #cbd5e1; padding: 48px 0 0; margin-top: 0; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr; gap: 32px; padding-bottom: 32px; }
.site-footer h4 { color: #fff; font-size: 16px; margin-bottom: 12px; }
.site-footer p { font-size: 13px; line-height: 1.8; }
.site-footer a { display: block; color: #94a3b8; font-size: 13.5px; padding: 3px 0; }
.site-footer a:hover { color: #fff; }
.footer-bottom {
  border-top: 1px solid #1e293b; padding: 18px 24px;
  display: flex; justify-content: space-between; flex-wrap: wrap; gap: 8px;
}
.footer-bottom p { font-size: 12.5px; color: #94a3b8; }
.beian-line { display: flex; align-items: center; flex-wrap: wrap; gap: 16px; }
.ga-link { display: inline-flex !important; align-items: center; gap: 4px; padding: 0 !important; }
.ga-icon { vertical-align: -2px; flex: none; }
.ga-link:hover { text-decoration: underline; }

/* ============ 响应式 ============ */
@media (max-width: 900px) {
  .grid-3, .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .about-grid, .contact-grid { grid-template-columns: 1fr; }
  .hero h1 { font-size: 32px; }
  .hero-stats { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1fr; }
}
@media (max-width: 560px) {
  .nav { display: none; }
  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
  .hero { padding: 64px 0 48px; }
  .section { padding: 48px 0; }
  .footer-bottom { flex-direction: column; text-align: center; }
}