:root {
  --green: #34C759;
  --green-hover: #2EB24C;
  --green-grad: linear-gradient(135deg, #34C759 0%, #00C7BE 100%);
  --text: #1D1D1F;
  --text-secondary: #6E6E73;
  --bg: #FFFFFF;
  --bg-alt: #F5F5F7;
  --dark: #0E0E10;
  --orange: #FF9500;
  --blue: #007AFF;
  --radius: 20px;
  --radius-btn: 12px;
  --max-width: 1080px;
  --shadow: 0 8px 30px rgba(0,0,0,0.06);
  --shadow-hover: 0 14px 40px rgba(0,0,0,0.10);
}

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

html { scroll-behavior: smooth; }

body {
  font-family: -apple-system, "PingFang SC", "SF Pro", "Helvetica Neue", sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

.container { max-width: var(--max-width); margin: 0 auto; padding: 0 24px; }

/* ============ 导航 ============ */
.nav {
  position: sticky; top: 0; z-index: 50;
  background: rgba(255,255,255,0.88);
  backdrop-filter: saturate(180%) blur(20px);
  border-bottom: 1px solid rgba(0,0,0,0.06);
}
.nav-inner { display: flex; align-items: center; justify-content: space-between; height: 60px; }
.brand { display: flex; align-items: center; gap: 8px; font-weight: 700; font-size: 18px; color: var(--text); text-decoration: none; }
.brand-mark { font-size: 20px; }
.nav-links { display: flex; align-items: center; gap: 24px; }
.nav-links a { color: var(--text-secondary); text-decoration: none; font-size: 14px; font-weight: 500; }
.nav-links a:hover { color: var(--text); }

/* 语言切换按钮 */
.lang-toggle {
  font-family: inherit; font-size: 13px; font-weight: 600; line-height: 1;
  color: var(--text-secondary); background: transparent;
  border: 1.5px solid #D2D2D7; border-radius: 999px;
  padding: 7px 12px; cursor: pointer;
  transition: all .18s ease;
}
.lang-toggle:hover { color: var(--green); border-color: var(--green); }

/* ============ 按钮 ============ */
.btn {
  display: inline-block; text-decoration: none; font-weight: 600;
  border-radius: var(--radius-btn); text-align: center;
  transition: all .18s ease; cursor: pointer; border: none;
}
.btn-primary { background: var(--green); color: #fff; }
.btn-primary:hover { background: var(--green-hover); transform: translateY(-1px); }
.btn-outline { background: transparent; color: var(--green); border: 1.5px solid var(--green); }
.btn-outline:hover { background: rgba(52,199,89,0.08); }
.btn-lg { padding: 14px 32px; font-size: 17px; }
.btn-sm { padding: 8px 18px; font-size: 14px; }

/* ============ Hero ============ */
.hero { padding: 80px 0 96px; background: linear-gradient(180deg, #F5F5F7 0%, #FFFFFF 70%); }
.hero-inner { display: grid; grid-template-columns: 1fr 1fr; gap: 56px; align-items: center; }
.hero-badge {
  display: inline-block; padding: 6px 14px; font-size: 13px; font-weight: 600;
  color: var(--green); background: rgba(52,199,89,0.1); border-radius: 999px; margin-bottom: 20px;
}
.hero-title { font-size: 52px; font-weight: 800; letter-spacing: -1.5px; line-height: 1.15; }
.hero-subtitle { font-size: 18px; color: var(--text-secondary); margin: 20px 0; }
.hero-cta { display: flex; gap: 16px; flex-wrap: wrap; margin: 28px 0 16px; }
.hero-meta { font-size: 13px; color: var(--text-secondary); }

/* 产品截图 */
.hero-visual { display: flex; justify-content: center; }
.hero-screenshot {
  width: 100%; max-width: 540px; height: auto;
  border-radius: 14px; box-shadow: var(--shadow-hover);
  border: 1px solid rgba(0,0,0,0.08);
}

/* ============ 数据条 ============ */
.stats { border-top: 1px solid #F0F0F2; border-bottom: 1px solid #F0F0F2; }
.stats-inner { display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; padding: 32px 0; text-align: center; }
.stat b { display: block; font-size: 28px; font-weight: 800; color: var(--green); }
.stat span { font-size: 13px; color: var(--text-secondary); }

/* ============ Section ============ */
.section { padding: 100px 0; }
.section-alt { background: var(--bg-alt); }
.section-title { text-align: center; font-size: 34px; font-weight: 700; margin-bottom: 56px; letter-spacing: -0.5px; }

/* 三大卖点 */
.cards-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.card {
  background: #fff; border: 1px solid #EFEFF1; border-radius: var(--radius);
  padding: 36px 28px; text-align: center; box-shadow: var(--shadow);
  transition: transform .2s ease, box-shadow .2s ease;
}
.card:hover { transform: translateY(-4px); box-shadow: var(--shadow-hover); }
.card-icon { font-size: 44px; margin-bottom: 18px; }
.card h3 { font-size: 21px; margin-bottom: 12px; }
.card p { color: var(--text-secondary); font-size: 15px; }

/* How it works */
.steps { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.step { text-align: center; padding: 32px 20px; }
.step-num {
  width: 48px; height: 48px; margin: 0 auto 16px; border-radius: 50%;
  background: var(--green-grad); color: #fff; font-size: 22px; font-weight: 800;
  display: flex; align-items: center; justify-content: center;
}
.step h3 { font-size: 19px; margin-bottom: 10px; }
.step p { color: var(--text-secondary); font-size: 14px; }

/* 功能网格 */
.feature-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
.feature {
  background: #fff; border: 1px solid #EFEFF1; border-radius: 14px;
  padding: 18px 20px; display: flex; align-items: flex-start; gap: 14px;
  transition: transform .18s ease, box-shadow .18s ease;
}
.feature:hover { transform: translateY(-2px); box-shadow: var(--shadow); }
.f-icon { font-size: 24px; }
.feature strong { display: block; font-size: 16px; margin-bottom: 3px; }
.feature span:last-child { color: var(--text-secondary); font-size: 13px; }

/* 对比表 */
.table-wrap { overflow-x: auto; }
.compare-table { width: 100%; border-collapse: collapse; background: #fff; border-radius: 16px; overflow: hidden; box-shadow: var(--shadow); }
.compare-table th, .compare-table td { padding: 16px 20px; text-align: center; font-size: 14px; border-bottom: 1px solid #F0F0F2; }
.compare-table th { background: #FAFAFC; font-weight: 600; }
.compare-table td:first-child { text-align: left; font-weight: 500; }
.compare-table .col-mac { color: var(--green); font-weight: 700; }
.yes { color: var(--green); }
.no { color: #C7C7CC; }
.partial { color: var(--orange); }

/* 用户评价 */
.testimonial { background: #fff; border: 1px solid #EFEFF1; border-radius: var(--radius); padding: 28px; box-shadow: var(--shadow); }
.testimonial p { font-size: 15px; margin-bottom: 12px; }
.testimonial span { color: var(--text-secondary); font-size: 13px; }

/* 安全区（深色） */
.security { background: var(--dark); padding: 100px 0; text-align: center; color: #fff; }
.security-title { font-size: 34px; font-weight: 700; margin-bottom: 48px; }
.security-grid { display: flex; gap: 20px; justify-content: center; flex-wrap: wrap; }
.sec-item {
  display: flex; align-items: center; gap: 8px;
  background: rgba(255,255,255,0.06); border: 1px solid rgba(255,255,255,0.12);
  border-radius: 999px; padding: 12px 24px; font-size: 15px; font-weight: 500;
}
.security-note { color: rgba(255,255,255,0.6); margin-top: 28px; font-size: 14px; }

/* 价格 */
.pricing { display: grid; grid-template-columns: repeat(2, 1fr); gap: 24px; max-width: 760px; margin: 0 auto; }
.price-card {
  position: relative; background: #fff; border: 1px solid #EFEFF1; border-radius: var(--radius);
  padding: 40px 32px; text-align: center; box-shadow: var(--shadow);
}
.price-card-pro { border: 2px solid var(--green); }
.pro-tag {
  position: absolute; top: -13px; left: 50%; transform: translateX(-50%);
  background: var(--green-grad); color: #fff; font-size: 12px; font-weight: 700;
  padding: 4px 14px; border-radius: 999px;
}
.price-card h3 { font-size: 20px; }
.price { font-size: 44px; font-weight: 800; margin: 16px 0; }
.price-note { font-size: 14px; font-weight: 400; color: var(--text-secondary); }
.price-card ul { list-style: none; text-align: left; margin: 20px 0 28px; }
.price-card li { padding: 7px 0; font-size: 15px; }
.price-card .btn { width: 100%; }

/* FAQ */
.faq { max-width: 720px; margin: 0 auto; }
.faq details { background: #fff; border: 1px solid #EFEFF1; border-radius: 12px; margin-bottom: 12px; padding: 18px 22px; }
.faq summary { font-weight: 600; cursor: pointer; font-size: 16px; }
.faq details p { color: var(--text-secondary); margin-top: 10px; font-size: 14px; }

/* 下载 CTA */
.download { padding: 100px 0; text-align: center; background: linear-gradient(180deg, #fff 0%, #F5F5F7 100%); }
.download h2 { font-size: 36px; font-weight: 800; letter-spacing: -0.5px; }
.download p { color: var(--text-secondary); margin: 12px 0 28px; }
.download-note { margin-top: 16px; font-size: 13px; }

/* Footer */
.footer { border-top: 1px solid #E5E5EA; padding: 28px 0; }
.footer-inner { display: flex; align-items: center; justify-content: space-between; color: var(--text-secondary); font-size: 13px; }
.footer-links { display: flex; gap: 24px; }
.footer-links a { color: var(--text-secondary); text-decoration: none; }
.footer-links a:hover { color: var(--text); }

/* ============ 响应式 ============ */
@media (max-width: 960px) {
  .hero-inner { grid-template-columns: 1fr; gap: 40px; }
  .hero-title { font-size: 40px; }
  .cards-3, .steps, .feature-grid { grid-template-columns: 1fr; }
  .stats-inner { grid-template-columns: repeat(2, 1fr); }
  .pricing { grid-template-columns: 1fr; }
}
@media (max-width: 600px) {
  .section { padding: 64px 0; }
  .nav-links a:not(.btn) { display: none; }
  .hero-title { font-size: 32px; }
  .btn-lg { width: 100%; }
}