/* 全局重置与基础样式 */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --font: -apple-system, BlinkMacSystemFont, "SF Pro Display", "Segoe UI", sans-serif;
  --radius: 12px;
  --transition: 0.25s ease;
}

html { scroll-behavior: smooth; }

body {
  font-family: var(--font);
  background: #fff;
  color: #1d1d1f;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

/* 导航栏 */
nav {
  position: fixed; top: 0; left: 0; right: 0;
  height: 56px;
  display: flex; align-items: center; justify-content: space-between;
  padding: 0 40px;
  background: rgba(255,255,255,0.85);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid rgba(0,0,0,0.06);
  z-index: 100;
}

nav .logo {
  font-size: 20px;
  font-weight: 700;
  letter-spacing: -0.5px;
  text-decoration: none;
  color: inherit;
}

nav .nav-cta {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 8px 20px;
  border-radius: 20px;
  font-size: 14px;
  font-weight: 500;
  text-decoration: none;
  transition: opacity var(--transition);
  color: #fff;
}
nav .nav-cta:hover { opacity: 0.85; }

/* Hero 区域 */
.hero {
  min-height: 100vh;
  display: flex; flex-direction: column;
  align-items: center; justify-content: center;
  text-align: center;
  padding: 100px 24px 60px;
}

.hero-badge {
  display: inline-block;
  padding: 6px 16px;
  border-radius: 20px;
  font-size: 13px;
  font-weight: 500;
  margin-bottom: 24px;
  letter-spacing: 0.3px;
}

.hero h1 {
  font-size: clamp(40px, 7vw, 80px);
  font-weight: 700;
  letter-spacing: -2px;
  line-height: 1.05;
  max-width: 800px;
  margin-bottom: 20px;
}

.hero p {
  font-size: clamp(16px, 2vw, 20px);
  color: #6e6e73;
  max-width: 560px;
  margin-bottom: 40px;
}

.hero-btns {
  display: flex; gap: 12px; flex-wrap: wrap; justify-content: center;
}

.btn-primary {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 14px 28px;
  border-radius: 30px;
  font-size: 16px;
  font-weight: 600;
  text-decoration: none;
  color: #fff;
  transition: transform var(--transition), opacity var(--transition);
}
.btn-primary:hover { transform: translateY(-2px); opacity: 0.9; }

.btn-secondary {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 14px 28px;
  border-radius: 30px;
  font-size: 16px;
  font-weight: 600;
  text-decoration: none;
  color: #1d1d1f;
  background: #f5f5f7;
  transition: background var(--transition);
}
.btn-secondary:hover { background: #e8e8ed; }

/* 功能特性区 */
.features {
  padding: 100px 24px;
  background: #f5f5f7;
}

.section-label {
  text-align: center;
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 1px;
  text-transform: uppercase;
  margin-bottom: 12px;
}

.section-title {
  text-align: center;
  font-size: clamp(28px, 4vw, 48px);
  font-weight: 700;
  letter-spacing: -1px;
  margin-bottom: 60px;
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 20px;
  max-width: 1100px;
  margin: 0 auto;
}

.feature-card {
  background: #fff;
  border-radius: var(--radius);
  padding: 32px 28px;
  transition: transform var(--transition), box-shadow var(--transition);
}
.feature-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 12px 40px rgba(0,0,0,0.08);
}

.feature-icon {
  width: 48px; height: 48px;
  border-radius: 12px;
  display: flex; align-items: center; justify-content: center;
  font-size: 22px;
  margin-bottom: 16px;
}

.feature-card h3 {
  font-size: 18px;
  font-weight: 600;
  margin-bottom: 8px;
  letter-spacing: -0.3px;
}

.feature-card p {
  font-size: 15px;
  color: #6e6e73;
  line-height: 1.6;
}

/* 订阅说明区 */
.subscription {
  padding: 100px 24px;
  max-width: 760px;
  margin: 0 auto;
  text-align: center;
}

.subscription h2 {
  font-size: clamp(24px, 3.5vw, 40px);
  font-weight: 700;
  letter-spacing: -1px;
  margin-bottom: 16px;
}

.subscription p {
  font-size: 15px;
  color: #6e6e73;
  margin-bottom: 8px;
}

/* CTA 区域 */
.cta-section {
  padding: 100px 24px;
  text-align: center;
}

.cta-section h2 {
  font-size: clamp(28px, 4vw, 52px);
  font-weight: 700;
  letter-spacing: -1.5px;
  margin-bottom: 16px;
}

.cta-section p {
  font-size: 18px;
  color: #6e6e73;
  margin-bottom: 40px;
}

/* 页脚 */
footer {
  border-top: 1px solid rgba(0,0,0,0.08);
  padding: 40px 24px;
  text-align: center;
}

footer .footer-links {
  display: flex; flex-wrap: wrap; justify-content: center; gap: 24px;
  margin-bottom: 20px;
}

footer a {
  font-size: 13px;
  color: #6e6e73;
  text-decoration: none;
  transition: color var(--transition);
}
footer a:hover { color: #1d1d1f; }

footer .copyright {
  font-size: 13px;
  color: #aeaeb2;
}

/* 响应式 */
@media (max-width: 600px) {
  nav { padding: 0 20px; }
  .hero-btns { flex-direction: column; align-items: center; }
  .btn-primary, .btn-secondary { width: 100%; max-width: 280px; justify-content: center; }
}