:root {
  --primary: #6366f1;
  --primary-dark: #4f46e5;
  --text: #1f2937;
  --light: #f9fafb;
  --gray: #6b7280;
}

* { margin:0; padding:0; box-sizing:border-box; }
body {
  font-family: system-ui, -apple-system, sans-serif;
  color: var(--text);
  background: var(--light);
  line-height: 1.6;
}
a { color: var(--primary); text-decoration: none; }

.container { max-width: 1200px; margin: 0 auto; padding: 0 20px; }

/* 导航 */
header {
  position: fixed;
  top: 0; left: 0; right: 0;
  background: white;
  box-shadow: 0 1px 3px rgba(0,0,0,0.1);
  z-index: 100;
}
nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 70px;
}
.logo { font-size: 1.6rem; font-weight: bold; color: var(--primary); }
.nav-links a { margin-left: 2rem; font-weight: 500; }

/* Hero */
.hero {
  padding: 140px 0 100px;
  text-align: center;
  background: linear-gradient(135deg, #f0f9ff 0%, #e0f2fe 100%);
}
.hero h1 { font-size: 3.4rem; margin-bottom: 1.2rem; }
.hero p { font-size: 1.4rem; color: #4b5563; max-width: 720px; margin: 0 auto 2.5rem; }
.hero-buttons { margin-top: 1.5rem; }
.btn {
  display: inline-block;
  padding: 14px 32px;
  font-size: 1.1rem;
  font-weight: 600;
  border-radius: 50px;
  transition: all 0.2s;
  margin: 0 12px 16px;
}
.btn-primary { background: var(--primary); color: white; }
.btn-primary:hover { background: var(--primary-dark); transform: translateY(-2px); }
.btn-outline { border: 2px solid var(--primary); color: var(--primary); }
.btn-outline:hover { background: var(--primary); color: white; }
.btn-large { font-size: 1.25rem; padding: 18px 48px; }

/* 功能 */
.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 2rem;
}
.feature-card {
  text-align: center;
  padding: 2rem;
  border-radius: 16px;
  background: white;
  box-shadow: 0 4px 12px rgba(0,0,0,0.08);
  transition: transform 0.25s;
}
.feature-card:hover { transform: translateY(-8px); }
.feature-card h3 { margin: 1.2rem 0 0.8rem; }

/* 下载区 */
.download-section { background: #f8fafc; padding: 100px 0; }
.download-content { text-align: center; }
.version { font-size: 1.3rem; font-weight: 600; margin-bottom: 0.5rem; }
.dev { color: var(--gray); margin-bottom: 2rem; }
.qr-hint { margin: 2.5rem 0 1.5rem; color: var(--gray); font-size: 1.1rem; }
#qrcode {
  margin: 1.5rem auto;
  background: white;
  padding: 16px;
  border-radius: 16px;
  box-shadow: 0 8px 30px rgba(0,0,0,0.12);
  display: inline-block;
}
.qr-desc { color: #4b5563; margin-top: 1rem; }
.ios-notice { margin-top: 4rem; color: var(--gray); }

/* 页脚 */
footer {
  background: #111827;
  color: white;
  text-align: center;
  padding: 4rem 0 2rem;
}
.footer-links a { color: #93c5fd; margin: 0 1rem; }

@media (max-width: 768px) {
  .hero h1 { font-size: 2.6rem; }
  .nav-links { display: none; }
  .btn { margin: 8px; }
}