* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Microsoft YaHei", Arial, sans-serif;
  color: #102033;
  background: #dfefff;
  line-height: 1.7;
}

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

.container {
  width: min(1180px, calc(100% - 48px));
  margin: 0 auto;
}

/* 首页大图：PC 全屏 */
.hero {
  position: relative;
  width: 100%;
  height: 100vh;
  min-height: 760px;
  background: url("/images/st001.jpg") center center / cover no-repeat;
  overflow: hidden;
}

.hero::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 220px;
  background: linear-gradient(
    to bottom,
    rgba(223, 239, 255, 0),
    #dfefff 88%
  );
  pointer-events: none;
}

/* 内容区 */
.section {
  position: relative;
  padding: 80px 0;
  overflow: hidden;
  background:
    radial-gradient(circle at 82% 18%, rgba(55,150,255,.22), transparent 30%),
    radial-gradient(circle at 14% 72%, rgba(38,203,255,.18), transparent 30%),
    linear-gradient(180deg, #dfefff 0%, #cfe6ff 48%, #b9dcff 100%);
}

.section::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background:
    linear-gradient(rgba(255,255,255,.34) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,.34) 1px, transparent 1px);
  background-size: 64px 64px;
  opacity: .42;
}

.section > .container {
  position: relative;
  z-index: 2;
}

.section-head {
  text-align: center;
  margin-bottom: 40px;
}

.section-head span,
.contact-label {
  display: inline-block;
  margin-bottom: 12px;
  color: #1677ff;
  font-size: 13px;
  font-weight: 800;
  letter-spacing: .16em;
}

.section h2,
.contact-section h2 {
  margin: 0;
  font-size: 42px;
  line-height: 1.2;
  color: #071b36;
  letter-spacing: -.04em;
}

.about-section {
  padding-top: 72px;
  padding-bottom: 72px;
}

.about-text {
  max-width: 920px;
  margin: 0 auto;
  text-align: center;
  font-size: 18px;
  color: #40546f;
}

.card-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 22px;
}

.card {
  min-height: 250px;
  padding: 30px;
  border-radius: 24px;
  background: rgba(255,255,255,.72);
  border: 1px solid rgba(255,255,255,.68);
  backdrop-filter: blur(16px);
  box-shadow: 0 18px 50px rgba(39,91,160,.14);
}

.card-icon {
  width: 46px;
  height: 46px;
  margin-bottom: 24px;
  border-radius: 15px;
  background: linear-gradient(135deg, #1677ff, #38bdf8);
  box-shadow: 0 0 34px rgba(22,119,255,.28);
}

.card h3 {
  margin: 0 0 14px;
  font-size: 22px;
  color: #071b36;
}

.card p {
  margin: 0;
  font-size: 15px;
  color: #50657f;
}

.contact-inner {
  display: grid;
  grid-template-columns: 1.15fr .85fr;
  gap: 42px;
  align-items: center;
}

.contact-section p {
  max-width: 680px;
  margin: 16px 0 0;
  color: #40546f;
}

.contact-box {
  padding: 32px;
  border-radius: 24px;
  background: rgba(255,255,255,.72);
  border: 1px solid rgba(255,255,255,.68);
  backdrop-filter: blur(16px);
  box-shadow: 0 18px 50px rgba(39,91,160,.14);
}

.contact-box p {
  margin: 0;
}

.contact-box p + p {
  margin-top: 12px;
}

.contact-box a {
  color: #1677ff;
  font-weight: 700;
}

.footer {
  padding: 34px 0;
  background: #071b36;
  color: rgba(255,255,255,.68);
  text-align: center;
  font-size: 14px;
}

.footer p {
  margin: 4px 0;
}

.footer a {
  color: rgba(255,255,255,.82);
}

@media (max-width: 960px) {
  .card-grid {
    grid-template-columns: repeat(2, 1fr);
  }

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

/* 手机端：去掉大空白 */
@media (max-width: 768px) {
  .container {
    width: min(100% - 32px, 1180px);
  }

  .hero {
    height: 260px !important;
    min-height: 260px !important;
    max-height: 260px !important;
    aspect-ratio: auto !important;
    background: url("/images/st001.jpg") center top / cover no-repeat !important;
  }

  .hero::after {
    height: 70px;
  }

  .section {
    padding: 52px 0;
  }

  .about-section {
    padding-top: 46px;
    padding-bottom: 46px;
  }

  .section-head {
    margin-bottom: 28px;
  }

  .section h2,
  .contact-section h2 {
    font-size: 32px;
  }

  .about-text {
    font-size: 16px;
    text-align: left;
  }

  .card-grid {
    grid-template-columns: 1fr;
  }
}