:root {
  color-scheme: light;
  font-family: Inter, "PingFang SC", "Microsoft YaHei", sans-serif;
  color: #172033;
  background: #f6f8fc;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  line-height: 1.75;
}

a { color: #4f46e5; }

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 14px max(24px, calc((100% - 1080px) / 2));
  background: rgba(255, 255, 255, .94);
  border-bottom: 1px solid #e8ebf2;
  backdrop-filter: blur(12px);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  color: #172033;
  font-size: 20px;
  font-weight: 800;
  text-decoration: none;
}

.brand img {
  width: 34px;
  height: 34px;
  flex: 0 0 34px;
}

.site-header nav {
  display: flex;
  flex-wrap: wrap;
  gap: 18px;
}

.site-header nav a {
  color: #4b5563;
  font-size: 14px;
  text-decoration: none;
}

.site-header nav a:hover { color: #4f46e5; }

main {
  width: min(900px, calc(100% - 32px));
  margin: 48px auto;
  padding: clamp(28px, 5vw, 56px);
  background: #fff;
  border: 1px solid #e8ebf2;
  border-radius: 24px;
  box-shadow: 0 24px 64px rgba(30, 41, 59, .08);
}

h1 {
  margin: 0 0 10px;
  font-size: clamp(32px, 6vw, 48px);
  line-height: 1.2;
}

h2 {
  margin: 32px 0 8px;
  color: #1e293b;
  font-size: 22px;
}

p, li { color: #526075; }

.intro {
  margin: 0 0 30px;
  color: #667085;
  font-size: 17px;
}

.meta {
  display: inline-block;
  margin-bottom: 18px;
  padding: 5px 12px;
  color: #4338ca;
  background: #eef2ff;
  border-radius: 999px;
  font-size: 13px;
  font-weight: 700;
}

.contact-card {
  margin-top: 24px;
  padding: 22px;
  background: #f8fafc;
  border: 1px solid #e2e8f0;
  border-radius: 16px;
}

.contact-card img {
  display: block;
  width: min(220px, 100%);
  margin: 18px 0 6px;
  border-radius: 12px;
}

.site-footer {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 18px;
  padding: 0 20px 44px;
  color: #667085;
  font-size: 14px;
}

.site-footer a { color: #667085; }

@media (max-width: 680px) {
  .site-header { align-items: flex-start; flex-direction: column; }
  .site-header nav { gap: 12px 16px; }
  main { margin: 24px auto; padding: 24px 20px; border-radius: 18px; }
}