/* === Reset & Base === */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; font-size: 16px; }
body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
  color: #1A1A2E; background: #FFFFFF; line-height: 1.6;
}
a { text-decoration: none; color: inherit; transition: color .2s; }
img { max-width: 100%; height: auto; display: block; }
ul, ol { list-style: none; }
h1,h2,h3,h4,h5,h6 { font-weight: 700; line-height: 1.3; }

/* === Layout === */
.container { max-width: 1200px; margin: 0 auto; padding: 0 20px; }
.section { padding: 80px 0; }
.section-alt { background: #F8FAFC; }
.section-dark { background: #1A1A2E; color: #fff; }

/* === Header === */
.header {
  position: sticky; top: 0; z-index: 1000;
  background: rgba(255,255,255,.97); backdrop-filter: blur(10px);
  border-bottom: 1px solid #E5E7EB; padding: 0 20px;
}
.header-inner {
  max-width: 1200px; margin: 0 auto;
  display: flex; align-items: center; justify-content: space-between;
  height: 70px;
}
.logo { font-size: 24px; font-weight: 800; color: #2563EB; letter-spacing: -0.5px; }
.logo span { color: #1A1A2E; }
.nav { display: flex; align-items: center; gap: 28px; }
.nav a { font-size: 15px; color: #4A4A6A; font-weight: 500; transition: color .2s; }
.nav a:hover { color: #2563EB; }
.btn-header {
  display: inline-block; padding: 8px 22px; border-radius: 8px;
  background: #2563EB; color: #fff !important; font-weight: 600; font-size: 14px;
  transition: background .2s, transform .2s;
}
.btn-header:hover { background: #1D4ED8; transform: translateY(-1px); }
.mobile-toggle { display: none; font-size: 28px; cursor: pointer; color: #1A1A2E; }

/* === Hero === */
.hero {
  background: linear-gradient(135deg, #EFF6FF 0%, #DBEAFE 50%, #BFDBFE 100%);
  padding: 100px 0 80px; text-align: center; position: relative; overflow: hidden;
}
.hero::before {
  content: ''; position: absolute; top: -50%; right: -20%; width: 600px; height: 600px;
  background: radial-gradient(circle, rgba(37,99,235,.08) 0%, transparent 70%);
  border-radius: 50%;
}
.hero h1 { font-size: 52px; color: #1A1A2E; margin-bottom: 20px; position: relative; }
.hero h1 em { font-style: normal; color: #2563EB; }
.hero .subtitle {
  font-size: 18px; color: #4A4A6A; max-width: 720px; margin: 0 auto 40px;
  line-height: 1.8; position: relative;
}
.hero-badges {
  display: flex; justify-content: center; gap: 24px; flex-wrap: wrap;
  margin-bottom: 40px; position: relative;
}
.hero-badge {
  display: inline-flex; align-items: center; gap: 8px;
  background: rgba(255,255,255,.8); padding: 10px 20px; border-radius: 50px;
  font-size: 14px; font-weight: 600; color: #1A1A2E;
  border: 1px solid rgba(37,99,235,.15);
}
.hero-badge .icon { font-size: 20px; }
.hero-cta { display: flex; justify-content: center; gap: 16px; flex-wrap: wrap; position: relative; }
.btn-primary {
  display: inline-block; padding: 16px 40px; border-radius: 12px;
  background: #2563EB; color: #fff; font-weight: 700; font-size: 18px;
  transition: background .2s, transform .2s, box-shadow .2s;
  box-shadow: 0 4px 14px rgba(37,99,235,.3);
}
.btn-primary:hover { background: #1D4ED8; transform: translateY(-2px); box-shadow: 0 6px 20px rgba(37,99,235,.4); }
.btn-secondary {
  display: inline-block; padding: 16px 40px; border-radius: 12px;
  background: #fff; color: #2563EB; font-weight: 700; font-size: 18px;
  border: 2px solid #2563EB; transition: all .2s;
}
.btn-secondary:hover { background: #EFF6FF; transform: translateY(-2px); }

/* === Section Titles === */
.section-title { text-align: center; margin-bottom: 60px; }
.section-title h2 { font-size: 36px; color: #1A1A2E; margin-bottom: 16px; }
.section-title p { font-size: 17px; color: #4A4A6A; max-width: 600px; margin: 0 auto; }

/* === Feature Cards === */
.features-grid {
  display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px;
}
.feature-card {
  background: #fff; border-radius: 16px; padding: 36px 28px;
  border: 1px solid #E5E7EB; transition: transform .3s, box-shadow .3s;
}
.feature-card:hover { transform: translateY(-6px); box-shadow: 0 12px 40px rgba(0,0,0,.08); }
.feature-icon {
  width: 56px; height: 56px; border-radius: 14px;
  display: flex; align-items: center; justify-content: center;
  font-size: 28px; margin-bottom: 20px;
  background: linear-gradient(135deg, #EFF6FF, #DBEAFE);
}
.feature-card h3 { font-size: 20px; margin-bottom: 12px; color: #1A1A2E; }
.feature-card p { font-size: 15px; color: #4A4A6A; line-height: 1.7; }

/* === Product Detail === */
.product-row {
  display: flex; align-items: center; gap: 60px; margin-bottom: 60px;
}
.product-row:last-child { margin-bottom: 0; }
.product-row.reverse { flex-direction: row-reverse; }
.product-text { flex: 1; }
.product-text h3 { font-size: 28px; margin-bottom: 16px; color: #1A1A2E; }
.product-text p { font-size: 16px; color: #4A4A6A; line-height: 1.8; margin-bottom: 12px; }
.product-visual {
  flex: 1; background: linear-gradient(135deg, #EFF6FF, #DBEAFE);
  border-radius: 20px; padding: 40px; text-align: center; min-height: 280px;
  display: flex; align-items: center; justify-content: center;
}
.product-visual .icon-large { font-size: 80px; }
.product-tags { display: flex; gap: 10px; flex-wrap: wrap; margin-top: 16px; }
.product-tag {
  display: inline-block; padding: 6px 14px; border-radius: 6px;
  background: #EFF6FF; color: #2563EB; font-size: 13px; font-weight: 600;
}

/* === Pricing === */
.pricing-grid {
  display: grid; grid-template-columns: repeat(2, 1fr); gap: 24px; max-width: 800px; margin: 0 auto;
}
.pricing-card {
  background: #fff; border-radius: 16px; padding: 36px; text-align: center;
  border: 2px solid #E5E7EB; transition: all .3s; position: relative;
}
.pricing-card:hover { border-color: #2563EB; box-shadow: 0 8px 30px rgba(37,99,235,.12); }
.pricing-card.popular { border-color: #2563EB; }
.pricing-card.popular::before {
  content: '最受欢迎'; position: absolute; top: -14px; left: 50%; transform: translateX(-50%);
  background: #2563EB; color: #fff; padding: 4px 20px; border-radius: 20px;
  font-size: 13px; font-weight: 600;
}
.pricing-card h3 { font-size: 22px; margin-bottom: 8px; color: #1A1A2E; }
.pricing-card .price { font-size: 42px; font-weight: 800; color: #2563EB; margin: 16px 0; }
.pricing-card .price small { font-size: 16px; color: #4A4A6A; font-weight: 400; }
.pricing-card .price-note { font-size: 14px; color: #4A4A6A; margin-bottom: 20px; }
.pricing-features { text-align: left; margin-bottom: 24px; }
.pricing-features li {
  padding: 8px 0; font-size: 15px; color: #4A4A6A;
  border-bottom: 1px solid #F3F4F6; display: flex; align-items: center; gap: 8px;
}
.pricing-features li::before { content: '✓'; color: #22C55E; font-weight: 700; }
.btn-pricing {
  display: inline-block; padding: 12px 32px; border-radius: 10px;
  background: #2563EB; color: #fff; font-weight: 600; font-size: 16px;
  transition: background .2s, transform .2s;
}
.btn-pricing:hover { background: #1D4ED8; transform: translateY(-2px); }
.btn-pricing-outline {
  display: inline-block; padding: 12px 32px; border-radius: 10px;
  background: transparent; color: #2563EB; font-weight: 600; font-size: 16px;
  border: 2px solid #2563EB; transition: all .2s;
}
.btn-pricing-outline:hover { background: #EFF6FF; }

/* === Pricing Table === */
.pricing-table { width: 100%; border-collapse: collapse; margin-top: 40px; }
.pricing-table th, .pricing-table td {
  padding: 16px 20px; text-align: center; border-bottom: 1px solid #E5E7EB;
}
.pricing-table th {
  background: #F8FAFC; font-size: 15px; font-weight: 600; color: #1A1A2E;
}
.pricing-table td { font-size: 15px; color: #4A4A6A; }
.pricing-table tr:hover td { background: #F8FAFC; }

/* === Security === */
.security-grid {
  display: grid; grid-template-columns: repeat(2, 1fr); gap: 24px;
}
.security-card {
  background: #fff; border-radius: 16px; padding: 32px;
  border: 1px solid #E5E7EB; display: flex; gap: 20px; align-items: flex-start;
}
.security-icon {
  width: 48px; height: 48px; min-width: 48px; border-radius: 12px;
  background: linear-gradient(135deg, #DCFCE7, #BBF7D0);
  display: flex; align-items: center; justify-content: center; font-size: 24px;
}
.security-card h3 { font-size: 18px; margin-bottom: 8px; }
.security-card p { font-size: 14px; color: #4A4A6A; line-height: 1.7; }
.cert-badges {
  display: flex; justify-content: center; gap: 32px; margin-top: 40px; flex-wrap: wrap;
}
.cert-badge {
  display: flex; align-items: center; gap: 10px;
  background: #F8FAFC; padding: 16px 24px; border-radius: 12px;
  border: 1px solid #E5E7EB;
}
.cert-badge .icon { font-size: 32px; }
.cert-badge .text { font-size: 14px; }
.cert-badge .text strong { display: block; font-size: 15px; color: #1A1A2E; }

/* === Reviews === */
.reviews-grid {
  display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px;
}
.review-card {
  background: #fff; border-radius: 16px; padding: 28px;
  border: 1px solid #E5E7EB; transition: transform .3s;
}
.review-card:hover { transform: translateY(-4px); }
.review-stars { color: #F59E0B; font-size: 18px; margin-bottom: 12px; letter-spacing: 2px; }
.review-text { font-size: 15px; color: #4A4A6A; line-height: 1.7; margin-bottom: 16px; font-style: italic; }
.review-author { font-size: 14px; font-weight: 600; color: #1A1A2E; }
.review-date { font-size: 13px; color: #9CA3AF; }

/* === FAQ === */
.faq-list { max-width: 800px; margin: 0 auto; }
.faq-item {
  border: 1px solid #E5E7EB; border-radius: 12px; margin-bottom: 12px;
  overflow: hidden; background: #fff;
}
.faq-question {
  display: block; padding: 20px 24px; font-size: 16px; font-weight: 600;
  color: #1A1A2E; cursor: pointer; transition: background .2s;
}
.faq-question:hover { background: #F8FAFC; }
.faq-question::after { content: '+'; float: right; font-size: 22px; color: #2563EB; font-weight: 300; }
.faq-item:target .faq-question::after { content: '−'; }
.faq-answer {
  max-height: 0; overflow: hidden; transition: max-height .3s ease;
  padding: 0 24px;
}
.faq-item:target .faq-answer { max-height: 600px; padding: 0 24px 20px; }
.faq-answer p { font-size: 15px; color: #4A4A6A; line-height: 1.8; margin-bottom: 8px; }
.faq-answer ol { padding-left: 20px; margin: 12px 0; }
.faq-answer ol li {
  font-size: 15px; color: #4A4A6A; line-height: 1.8; margin-bottom: 6px;
  list-style: decimal; padding-left: 4px;
}

/* === CTA Bottom === */
.cta-bottom {
  background: linear-gradient(135deg, #1E40AF, #2563EB, #3B82F6);
  padding: 80px 0; text-align: center; color: #fff;
}
.cta-bottom h2 { font-size: 36px; margin-bottom: 16px; }
.cta-bottom p { font-size: 18px; opacity: .9; margin-bottom: 32px; max-width: 600px; margin-left: auto; margin-right: auto; }
.btn-cta-white {
  display: inline-block; padding: 16px 48px; border-radius: 12px;
  background: #fff; color: #2563EB; font-weight: 700; font-size: 18px;
  transition: transform .2s, box-shadow .2s;
}
.btn-cta-white:hover { transform: translateY(-2px); box-shadow: 0 8px 24px rgba(0,0,0,.15); }

/* === Footer === */
.footer { background: #111827; color: #D1D5DB; padding: 60px 0 30px; }
.footer-grid {
  display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 40px; margin-bottom: 40px;
}
.footer-brand .logo { color: #60A5FA; font-size: 22px; margin-bottom: 12px; display: inline-block; }
.footer-brand .logo span { color: #fff; }
.footer-brand p { font-size: 14px; line-height: 1.7; color: #9CA3AF; }
.footer h4 { font-size: 15px; color: #fff; margin-bottom: 16px; font-weight: 600; }
.footer ul li { margin-bottom: 10px; }
.footer ul li a { font-size: 14px; color: #9CA3AF; transition: color .2s; }
.footer ul li a:hover { color: #60A5FA; }
.footer-bottom {
  border-top: 1px solid #374151; padding-top: 24px;
  display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: 12px;
}
.footer-bottom p { font-size: 13px; color: #6B7280; }

/* === Page Hero (Inner Pages) === */
.page-hero {
  background: linear-gradient(135deg, #EFF6FF, #DBEAFE);
  padding: 60px 0; text-align: center;
}
.page-hero h1 { font-size: 40px; color: #1A1A2E; margin-bottom: 12px; }
.page-hero p { font-size: 17px; color: #4A4A6A; }
.breadcrumb {
  display: flex; justify-content: center; gap: 8px; margin-top: 16px; font-size: 14px;
}
.breadcrumb a { color: #2563EB; }
.breadcrumb span { color: #9CA3AF; }

/* === Guide Steps === */
.guide-steps { max-width: 800px; margin: 0 auto; }
.guide-step {
  display: flex; gap: 24px; margin-bottom: 40px; align-items: flex-start;
}
.step-number {
  width: 48px; height: 48px; min-width: 48px; border-radius: 50%;
  background: #2563EB; color: #fff; font-size: 20px; font-weight: 700;
  display: flex; align-items: center; justify-content: center;
}
.step-content h3 { font-size: 20px; margin-bottom: 8px; }
.step-content p { font-size: 15px; color: #4A4A6A; line-height: 1.8; }

/* === Help Center === */
.help-grid {
  display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px;
}
.help-card {
  background: #fff; border-radius: 16px; padding: 32px; text-align: center;
  border: 1px solid #E5E7EB; transition: all .3s;
}
.help-card:hover { border-color: #2563EB; transform: translateY(-4px); box-shadow: 0 8px 24px rgba(37,99,235,.1); }
.help-card .icon { font-size: 40px; margin-bottom: 16px; }
.help-card h3 { font-size: 18px; margin-bottom: 10px; }
.help-card p { font-size: 14px; color: #4A4A6A; margin-bottom: 16px; line-height: 1.7; }
.help-card a.card-link {
  display: inline-block; padding: 8px 20px; border-radius: 8px;
  background: #EFF6FF; color: #2563EB; font-weight: 600; font-size: 14px;
  transition: background .2s;
}
.help-card a.card-link:hover { background: #DBEAFE; }

/* === Legal Pages === */
.legal-content { max-width: 800px; margin: 0 auto; }
.legal-content h2 { font-size: 24px; margin: 32px 0 16px; color: #1A1A2E; }
.legal-content h3 { font-size: 20px; margin: 24px 0 12px; color: #1A1A2E; }
.legal-content p { font-size: 15px; color: #4A4A6A; line-height: 1.8; margin-bottom: 12px; }
.legal-content ul { padding-left: 20px; margin-bottom: 16px; }
.legal-content ul li {
  font-size: 15px; color: #4A4A6A; line-height: 1.8; margin-bottom: 6px;
  list-style: disc; padding-left: 4px;
}

/* === Download Page === */
.download-grid {
  display: grid; grid-template-columns: repeat(2, 1fr); gap: 24px; max-width: 800px; margin: 0 auto;
}
.download-card {
  background: #fff; border-radius: 16px; padding: 36px; text-align: center;
  border: 1px solid #E5E7EB; transition: all .3s;
}
.download-card:hover { border-color: #2563EB; transform: translateY(-4px); box-shadow: 0 8px 24px rgba(37,99,235,.1); }
.download-card .icon { font-size: 48px; margin-bottom: 16px; }
.download-card h3 { font-size: 20px; margin-bottom: 8px; }
.download-card p { font-size: 14px; color: #4A4A6A; margin-bottom: 20px; }
.btn-download {
  display: inline-block; padding: 12px 32px; border-radius: 10px;
  background: #2563EB; color: #fff; font-weight: 600; font-size: 16px;
  transition: background .2s, transform .2s;
}
.btn-download:hover { background: #1D4ED8; transform: translateY(-2px); }

/* === Responsive === */
@media (max-width: 1024px) {
  .features-grid, .reviews-grid, .help-grid { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: repeat(2, 1fr); }
  .product-row { flex-direction: column; gap: 30px; }
  .product-row.reverse { flex-direction: column; }
}
@media (max-width: 768px) {
  .nav { display: none; }
  .mobile-toggle { display: block; }
  .hero h1 { font-size: 32px; }
  .hero .subtitle { font-size: 16px; }
  .section { padding: 50px 0; }
  .section-title h2 { font-size: 28px; }
  .features-grid, .reviews-grid, .help-grid, .security-grid, .pricing-grid, .download-grid {
    grid-template-columns: 1fr;
  }
  .footer-grid { grid-template-columns: 1fr; }
  .hero-cta { flex-direction: column; align-items: center; }
  .btn-primary, .btn-secondary { width: 100%; max-width: 300px; text-align: center; }
  .page-hero h1 { font-size: 28px; }
  .cta-bottom h2 { font-size: 28px; }
  .pricing-table { font-size: 13px; }
  .pricing-table th, .pricing-table td { padding: 10px 8px; }
}
@media (max-width: 480px) {
  .hero h1 { font-size: 26px; }
  .hero-badges { flex-direction: column; align-items: center; }
  .container { padding: 0 16px; }
}