:root {
  --bg: #f5f7fb;
  --surface: #ffffff;
  --text: #1f2937;
  --muted: #6b7280;
  --primary: #2563eb;
  --primary-dark: #1d4ed8;
  --border: #e5e7eb;
  --shadow: 0 10px 30px rgba(15, 23, 42, 0.08);
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.7;
}

a {
  color: var(--primary);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

.container {
  width: min(1100px, calc(100% - 32px));
  margin: 0 auto;
}

.narrow {
  width: min(820px, calc(100% - 32px));
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  background: rgba(255, 255, 255, 0.96);
  border-bottom: 1px solid var(--border);
  backdrop-filter: blur(8px);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  min-height: 64px;
}

.logo {
  font-weight: 700;
  color: var(--text);
  white-space: nowrap;
}

.nav {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  font-size: 14px;
}

.nav a {
  color: var(--muted);
}

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

.hero {
  padding: 72px 0 56px;
  background: linear-gradient(180deg, #eef4ff 0%, var(--bg) 100%);
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 28px;
  align-items: stretch;
}

.eyebrow {
  display: inline-block;
  margin: 0 0 12px;
  padding: 6px 12px;
  border-radius: 999px;
  background: #dbeafe;
  color: var(--primary-dark);
  font-size: 13px;
}

.hero h1 {
  margin: 0 0 16px;
  font-size: clamp(32px, 5vw, 48px);
  line-height: 1.15;
}

.lead {
  margin: 0 0 24px;
  color: var(--muted);
  font-size: 18px;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.btn {
  display: inline-block;
  padding: 12px 20px;
  border-radius: 10px;
  font-weight: 600;
}

.btn-primary {
  background: var(--primary);
  color: #fff;
}

.btn-primary:hover {
  background: var(--primary-dark);
  text-decoration: none;
}

.btn-ghost {
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--text);
}

.btn-ghost:hover {
  text-decoration: none;
  border-color: #cbd5e1;
}

.hero-card,
.card,
.contact-box,
.doc {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 16px;
  box-shadow: var(--shadow);
}

.hero-card {
  padding: 28px;
}

.hero-card h2 {
  margin-top: 0;
}

.hero-card ul {
  margin: 0;
  padding-left: 18px;
}

.section {
  padding: 56px 0;
}

.section-alt {
  background: #eef2f7;
}

.section-title {
  margin: 0 0 12px;
  font-size: 28px;
}

.section-desc {
  margin: 0 0 28px;
  color: var(--muted);
}

.cards {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.card {
  padding: 24px;
}

.card h3 {
  margin-top: 0;
}

.feature-list {
  display: grid;
  gap: 14px;
}

.feature-item {
  display: grid;
  grid-template-columns: 140px 1fr;
  gap: 12px;
  padding: 16px 18px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
}

.feature-item strong {
  color: var(--primary-dark);
}

.contact-box,
.doc {
  padding: 28px;
}

.contact-box p,
.doc p,
.doc li {
  margin: 0 0 12px;
}

.hint {
  color: var(--muted);
  font-size: 14px;
}

.site-footer {
  padding: 28px 0 36px;
  background: #111827;
  color: #d1d5db;
  text-align: center;
  font-size: 14px;
}

.site-footer a {
  color: #93c5fd;
}

.footer-inner p {
  margin: 8px 0;
}

.icp {
  color: #9ca3af;
  font-size: 13px;
}

.doc-page {
  padding: 40px 0 64px;
}

.doc h1 {
  margin-top: 0;
}

.doc h2 {
  margin-top: 28px;
  font-size: 20px;
}

@media (max-width: 900px) {
  .hero-grid,
  .cards {
    grid-template-columns: 1fr;
  }

  .feature-item {
    grid-template-columns: 1fr;
  }

  .header-inner {
    align-items: flex-start;
    flex-direction: column;
    padding: 12px 0;
  }
}