:root {
  --brand: #2563eb;
  --brand-dark: #1d4ed8;
  --ink: #1f2937;
  --ink-soft: #5b6675;
  --line: #e5e7eb;
  --bg-alt: #f7f9fc;
  --radius: 12px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--ink);
  background: #fff;
  font: 400 16px/1.7 -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  -webkit-font-smoothing: antialiased;
}

h1,
h2,
p,
ul {
  margin: 0;
}

ul {
  padding: 0;
  list-style: none;
}

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

.container {
  width: 100%;
  max-width: 1140px;
  margin: 0 auto;
  padding: 0 24px;
}

/* 顶部导航 */
.nav {
  position: sticky;
  top: 0;
  z-index: 10;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--line);
}

.nav-inner {
  display: flex;
  align-items: center;
  gap: 24px;
  height: 64px;
}

.site-name {
  font-size: 20px;
  font-weight: 700;
  letter-spacing: 0.5px;
  color: var(--brand);
  white-space: nowrap;
}

.nav-links {
  display: flex;
  gap: 28px;
  margin-left: auto;
  font-size: 15px;
  color: var(--ink-soft);
}

.nav-links a:hover {
  color: var(--brand);
}

.nav-cta {
  padding: 8px 18px;
  border-radius: 999px;
  background: var(--brand);
  color: #fff;
  font-size: 14px;
  white-space: nowrap;
}

.nav-cta:hover {
  background: var(--brand-dark);
}

/* 横幅 */
.hero {
  background: linear-gradient(135deg, #1e40af 0%, #2563eb 55%, #3b82f6 100%);
  color: #fff;
}

.hero-inner {
  padding: 96px 24px 104px;
  text-align: center;
}

.hero h1 {
  font-size: 44px;
  line-height: 1.3;
  font-weight: 700;
}

.hero-sub {
  max-width: 720px;
  margin: 20px auto 0;
  font-size: 17px;
  color: rgba(255, 255, 255, 0.86);
}

.hero-btns {
  display: flex;
  justify-content: center;
  gap: 14px;
  margin-top: 36px;
}

.btn {
  padding: 12px 30px;
  border-radius: 999px;
  font-size: 16px;
  transition: 0.18s;
}

.btn-primary {
  background: #fff;
  color: var(--brand);
  font-weight: 600;
}

.btn-primary:hover {
  transform: translateY(-1px);
}

.btn-ghost {
  border: 1px solid rgba(255, 255, 255, 0.6);
  color: #fff;
}

.btn-ghost:hover {
  background: rgba(255, 255, 255, 0.14);
}

/* 通用分区 */
.section {
  padding: 84px 0;
}

.section-alt {
  background: var(--bg-alt);
  border-top: 1px solid var(--line);
}

.section-title {
  font-size: 30px;
  text-align: center;
  font-weight: 700;
}

.section-lead {
  margin-top: 12px;
  text-align: center;
  color: var(--ink-soft);
}

/* 关于我们 */
.about-grid {
  display: grid;
  grid-template-columns: 1.35fr 1fr;
  gap: 56px;
  margin-top: 48px;
  align-items: start;
}

.about-text p + p {
  margin-top: 18px;
}

.about-text p {
  color: #414c5c;
}

.stats {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
}

.stats li {
  padding: 24px 20px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--bg-alt);
  text-align: center;
}

.stats strong {
  display: block;
  font-size: 34px;
  line-height: 1.1;
  color: var(--brand);
}

.stats strong span {
  font-size: 18px;
  margin-left: 2px;
}

.stat-label {
  display: block;
  margin-top: 8px;
  font-size: 14px;
  color: var(--ink-soft);
}

/* 联系我们 */
.contact-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
  margin-top: 48px;
}

.contact-item {
  padding: 24px 26px;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.contact-k {
  font-size: 14px;
  color: var(--ink-soft);
}

.contact-v {
  margin-top: 8px;
  font-size: 18px;
  font-weight: 600;
  word-break: break-all;
}

.contact-v.link:hover {
  color: var(--brand);
}

/* 底部 */
.footer {
  background: #111827;
  color: #9aa4b2;
  padding: 40px 0;
  font-size: 14px;
}

.footer-inner {
  text-align: center;
}

.footer-name {
  color: #fff;
  font-size: 16px;
  font-weight: 600;
}

.footer-legal {
  margin-top: 12px;
}

.footer-legal a:hover {
  color: #fff;
}

.dot {
  margin: 0 8px;
}

@media (max-width: 900px) {
  .about-grid {
    grid-template-columns: 1fr;
    gap: 36px;
  }

  .hero h1 {
    font-size: 34px;
  }

  .hero-inner {
    padding: 72px 24px 80px;
  }

  .section {
    padding: 64px 0;
  }
}

@media (max-width: 640px) {
  .container {
    padding: 0 18px;
  }

  .nav-links {
    display: none;
  }

  .nav-cta {
    margin-left: auto;
  }

  .hero h1 {
    font-size: 27px;
  }

  .hero-sub {
    font-size: 15px;
  }

  .hero-btns {
    flex-direction: column;
    align-items: stretch;
  }

  .btn {
    text-align: center;
  }

  .section-title {
    font-size: 24px;
  }

  .contact-grid,
  .stats {
    grid-template-columns: 1fr;
  }
}