* { margin: 0; padding: 0; box-sizing: border-box; }
:root {
  --primary: #1a56db;
  --primary-dark: #1242a8;
  --text: #1f2937;
  --muted: #6b7280;
  --bg-alt: #f6f8fb;
  --radius: 14px;
}
html { scroll-behavior: smooth; }
body {
  font-family: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  color: var(--text);
  line-height: 1.7;
  background: #fff;
}
.container { max-width: 1120px; margin: 0 auto; padding: 0 24px; }
a { text-decoration: none; color: inherit; }

/* 导航 */
.nav {
  position: sticky; top: 0; z-index: 100;
  background: rgba(255,255,255,.92);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid #eef0f4;
}
.nav-inner { display: flex; align-items: center; justify-content: space-between; height: 64px; }
.logo { font-size: 22px; font-weight: 800; letter-spacing: 1px; }
.logo span { color: var(--primary); }
.nav-links { display: flex; gap: 28px; align-items: center; }
.nav-links a { font-size: 15px; color: var(--text); transition: color .2s; }
.nav-links a:hover { color: var(--primary); }
.nav-cta {
  background: var(--primary); color: #fff !important;
  padding: 8px 18px; border-radius: 999px;
}
.menu-btn { display: none; background: none; border: none; font-size: 24px; cursor: pointer; }

/* Hero */
.hero {
  background: linear-gradient(160deg, #eef4ff 0%, #f8fbff 55%, #fff 100%);
  padding: 96px 0 80px;
}
.hero-inner { text-align: center; }
.hero h1 { font-size: 46px; line-height: 1.3; font-weight: 800; }
.hero h1 em { font-style: normal; color: var(--primary); }
.hero-sub { margin: 22px auto 34px; font-size: 17px; color: var(--muted); }
.hero-actions { display: flex; gap: 16px; justify-content: center; }
.btn {
  display: inline-block; padding: 13px 34px; border-radius: 999px;
  font-size: 16px; font-weight: 600; cursor: pointer; border: none; transition: all .2s;
}
.btn-primary { background: var(--primary); color: #fff; box-shadow: 0 8px 20px rgba(26,86,219,.28); }
.btn-primary:hover { background: var(--primary-dark); transform: translateY(-2px); }
.btn-ghost { background: #fff; color: var(--primary); border: 1.5px solid var(--primary); }
.btn-ghost:hover { background: #eef4ff; }
.hero-stats {
  margin: 56px auto 0; display: flex; justify-content: center; gap: 72px;
}
.hero-stats b { display: block; font-size: 32px; color: var(--primary); }
.hero-stats span { font-size: 14px; color: var(--muted); }

/* 通用区块 */
.section { padding: 88px 0; }
.section-alt { background: var(--bg-alt); }
.sec-title { text-align: center; font-size: 32px; font-weight: 800; }
.sec-sub { text-align: center; color: var(--muted); margin: 12px 0 48px; }

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

.card {
  background: #fff; border: 1px solid #eef0f4; border-radius: var(--radius);
  padding: 32px 26px; transition: all .25s;
}
.card:hover { transform: translateY(-6px); box-shadow: 0 16px 36px rgba(31,41,55,.08); }
.card-icon { font-size: 34px; margin-bottom: 14px; }
.card h3 { font-size: 19px; margin-bottom: 10px; }
.card p { font-size: 14.5px; color: var(--muted); }

/* 流程 */
.steps { list-style: none; display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.steps li {
  background: #fff; border-radius: var(--radius); padding: 28px 24px;
  border-top: 4px solid var(--primary);
}
.steps b { font-size: 17px; display: block; margin-bottom: 8px; }
.steps p { font-size: 14px; color: var(--muted); }

/* 案例 */
.case {
  background: #fff; border: 1px solid #e6eaf2; border-radius: var(--radius);
  text-align: center; padding: 30px 10px; font-weight: 600; font-size: 16px;
  color: var(--text); transition: all .2s;
}
.case:hover { border-color: var(--primary); color: var(--primary); }

/* 关于 */
.about-inner { display: grid; grid-template-columns: 1.4fr 1fr; gap: 56px; align-items: center; }
.about-inner p { color: var(--muted); margin-bottom: 14px; }
.about-list { list-style: none; margin-top: 18px; }
.about-list li { padding: 6px 0; font-weight: 600; }
.about-card {
  background: #fff; border-radius: var(--radius); padding: 36px 32px;
  box-shadow: 0 16px 40px rgba(26,86,219,.10); border: 1px solid #e8eefc;
}
.about-card h3 { margin-bottom: 16px; font-size: 20px; }
.about-card p { margin-bottom: 12px; color: var(--text); }

/* 联系 */
.contact-inner { max-width: 640px; margin: 0 auto; }
.contact-form { display: grid; gap: 16px; }
.contact-form input, .contact-form textarea {
  width: 100%; padding: 14px 18px; border: 1.5px solid #e2e7f0; border-radius: 10px;
  font-size: 15px; font-family: inherit; outline: none; transition: border .2s;
}
.contact-form input:focus, .contact-form textarea:focus { border-color: var(--primary); }
.contact-form .btn { width: 100%; }
.contact-tip { text-align: center; color: var(--primary); margin-top: 14px; min-height: 24px; font-weight: 600; }

/* 页脚 */
.footer { background: #101828; color: #cbd2dd; padding: 56px 0 0; }
.footer-inner { display: flex; justify-content: space-between; align-items: flex-start; flex-wrap: wrap; gap: 24px; }
.footer-logo { color: #fff; margin-bottom: 8px; }
.footer p { font-size: 14px; color: #8b95a5; }
.footer-links { display: flex; gap: 24px; }
.footer-links a { font-size: 14px; color: #cbd2dd; }
.footer-links a:hover { color: #fff; }
.copyright {
  margin-top: 40px; padding: 20px 24px; border-top: 1px solid #232f42;
  text-align: center; font-size: 13px; color: #8b95a5;
}

/* 响应式 */
@media (max-width: 900px) {
  .grid-3 { grid-template-columns: repeat(2, 1fr); }
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .steps { grid-template-columns: repeat(2, 1fr); }
  .about-inner { grid-template-columns: 1fr; gap: 32px; }
  .hero h1 { font-size: 34px; }
  .hero-stats { gap: 40px; }
}
@media (max-width: 560px) {
  .nav-links {
    display: none; position: absolute; top: 64px; left: 0; right: 0;
    background: #fff; flex-direction: column; padding: 18px 24px; gap: 16px;
    border-bottom: 1px solid #eef0f4; box-shadow: 0 12px 24px rgba(0,0,0,.06);
  }
  .nav-links.open { display: flex; }
  .menu-btn { display: block; }
  .grid-3, .grid-4, .steps { grid-template-columns: 1fr; }
  .hero { padding: 64px 0 56px; }
  .hero h1 { font-size: 28px; }
  .hero-sub { font-size: 15px; }
  .pc-br { display: none; }
  .hero-stats { gap: 24px; }
  .hero-stats b { font-size: 24px; }
  .section { padding: 60px 0; }
  .sec-title { font-size: 25px; }
}