/* ============================================================
   UQBrowser 官网样式
   ============================================================ */

:root {
  --c1: #1a73e8;
  --c1d: #1557b0;
  --c1l: #e8f0fe;
  --bg: #ffffff;
  --bg2: #f8f9fa;
  --tx: #202124;
  --tx2: #5f6368;
  --tx3: #9aa0a6;
  --r: 12px;
  --sh: 0 2px 8px rgba(0,0,0,.08);
}

* { margin: 0; padding: 0; box-sizing: border-box; }

body {
  font-family: -apple-system, "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
  color: var(--tx);
  line-height: 1.6;
  background: var(--bg);
}

.container { max-width: 1100px; margin: 0 auto; padding: 0 24px; }

/* Nav */
.nav {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  background: rgba(255,255,255,.92); backdrop-filter: blur(12px);
  border-bottom: 1px solid #e8eaed;
}
.nav-inner { display: flex; align-items: center; justify-content: space-between; height: 56px; }
.logo { display: flex; align-items: center; gap: 10px; font-size: 18px; font-weight: 700; color: var(--c1); text-decoration: none; }
.logo img { border-radius: 6px; }
.nav-links { display: flex; gap: 24px; }
.nav-links a { color: var(--tx2); text-decoration: none; font-size: 14px; transition: color .2s; }
.nav-links a:hover { color: var(--c1); }

/* Hero */
.hero {
  padding: 140px 0 80px;
  text-align: center;
  background: linear-gradient(180deg, var(--c1l) 0%, var(--bg) 100%);
}
.hero h1 { font-size: 48px; font-weight: 800; letter-spacing: -.5px; color: var(--tx); }
.hero-sub { font-size: 22px; color: var(--c1); font-weight: 600; margin-top: 8px; }
.hero-desc { font-size: 17px; color: var(--tx2); margin-top: 20px; line-height: 1.8; }
.hero-btns { margin-top: 32px; display: flex; gap: 16px; justify-content: center; }
.hero-meta { margin-top: 20px; font-size: 13px; color: var(--tx3); }

/* Buttons */
.btn {
  display: inline-block; padding: 12px 32px; border-radius: 8px;
  font-size: 15px; font-weight: 600; text-decoration: none; transition: all .2s; cursor: pointer; border: none;
}
.btn-primary { background: var(--c1); color: #fff; }
.btn-primary:hover { background: var(--c1d); transform: translateY(-1px); box-shadow: 0 4px 12px rgba(26,115,232,.3); }
.btn-outline { background: transparent; color: var(--c1); border: 2px solid var(--c1); }
.btn-outline:hover { background: var(--c1l); }
.btn-lg { padding: 16px 48px; font-size: 17px; border-radius: 10px; }

/* Section */
.section { padding: 80px 0; }
.section-alt { background: var(--bg2); }
.section-title { font-size: 32px; font-weight: 700; text-align: center; margin-bottom: 12px; }
.section-desc { text-align: center; color: var(--tx2); font-size: 16px; margin-bottom: 48px; }

/* Features grid */
.features-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; margin-top: 40px; }
.feature-card {
  background: var(--bg); border-radius: var(--r); padding: 32px 24px;
  box-shadow: var(--sh); transition: transform .2s, box-shadow .2s;
}
.feature-card:hover { transform: translateY(-4px); box-shadow: 0 8px 24px rgba(0,0,0,.1); }
.feature-icon { font-size: 36px; margin-bottom: 16px; }
.feature-card h3 { font-size: 18px; margin-bottom: 10px; }
.feature-card p { font-size: 14px; color: var(--tx2); line-height: 1.7; }

/* PDF grid */
.pdf-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; margin-top: 40px; }
.pdf-cat {
  background: var(--bg); border-radius: var(--r); padding: 24px;
  border-left: 4px solid var(--c1);
}
.pdf-cat h4 { font-size: 16px; color: var(--c1); margin-bottom: 8px; }
.pdf-cat p { font-size: 14px; color: var(--tx2); line-height: 1.7; }

/* Download */
.download-section { text-align: center; }
.download-card {
  display: inline-flex; align-items: center; gap: 40px;
  background: var(--bg2); border-radius: 16px; padding: 32px 48px;
  margin-top: 32px;
}
.download-info { text-align: left; }
.download-info h3 { font-size: 20px; }
.download-info p { font-size: 14px; color: var(--tx2); margin-top: 4px; }
.download-meta { font-size: 13px !important; color: var(--tx3) !important; }
.download-note { margin-top: 16px; font-size: 13px; color: var(--tx3); }

/* Footer */
.footer { background: #1a1a2e; color: #ccc; padding: 48px 0 32px; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr; gap: 40px; }
.footer h4 { color: #fff; font-size: 15px; margin-bottom: 12px; }
.footer p, .footer a { font-size: 13px; color: #999; line-height: 2; }
.footer a { text-decoration: none; display: block; }
.footer a:hover { color: #fff; }

/* Responsive */
@media (max-width: 768px) {
  .hero h1 { font-size: 32px; }
  .hero-sub { font-size: 18px; }
  .features-grid, .pdf-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; gap: 24px; }
  .nav-links { display: none; }
  .download-card { flex-direction: column; gap: 20px; padding: 24px; }
  .download-info { text-align: center; }
}