/* === Reset & Base === */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; font-size: 16px; }
body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans SC", sans-serif;
  color: #1A1A2E; background: #FFFFFF; line-height: 1.7;
}
a { text-decoration: none; color: inherit; transition: color .2s; }
ul { list-style: none; }
img { max-width: 100%; display: block; }

/* === Layout === */
.container { max-width: 1200px; margin: 0 auto; padding: 0 24px; }
.section { padding: 80px 0; }
.section-alt { background: #F8FAFC; }
.text-center { text-align: center; }

/* === Header === */
.site-header {
  position: sticky; top: 0; z-index: 1000;
  background: rgba(255,255,255,.96); backdrop-filter: blur(10px);
  border-bottom: 1px solid #E5E7EB;
}
.header-inner {
  display: flex; align-items: center; justify-content: space-between;
  height: 72px; max-width: 1200px; margin: 0 auto; padding: 0 24px;
}
.logo { font-size: 24px; font-weight: 800; color: #2563EB; letter-spacing: -0.5px; }
.logo span { color: #1A1A2E; }
.nav-links { display: flex; align-items: center; gap: 32px; }
.nav-links a { font-size: 15px; font-weight: 500; color: #4A4A6A; transition: color .2s; }
.nav-links a:hover { color: #2563EB; }
.btn {
  display: inline-flex; align-items: center; justify-content: center;
  padding: 12px 28px; border-radius: 8px; font-size: 15px; font-weight: 600;
  transition: all .25s; cursor: pointer; border: none;
}
.btn-primary { background: #2563EB; color: #fff; }
.btn-primary:hover { background: #1D4ED8; transform: translateY(-1px); box-shadow: 0 4px 16px rgba(37,99,235,.35); }
.btn-outline { border: 2px solid #2563EB; color: #2563EB; background: transparent; }
.btn-outline:hover { background: #2563EB; color: #fff; }
.btn-lg { padding: 16px 40px; font-size: 17px; border-radius: 10px; }
.btn-white { background: #fff; color: #2563EB; }
.btn-white:hover { background: #F0F4FF; transform: translateY(-1px); }
.mobile-menu-btn { display: none; background: none; border: none; font-size: 28px; color: #1A1A2E; cursor: pointer; }

/* === Hero === */
.hero {
  background: linear-gradient(135deg, #EFF6FF 0%, #DBEAFE 50%, #E0E7FF 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; font-weight: 800; line-height: 1.2; margin-bottom: 20px; color: #1A1A2E; }
.hero h1 em { font-style: normal; color: #2563EB; }
.hero .subtitle { font-size: 20px; color: #4A4A6A; max-width: 680px; margin: 0 auto 36px; line-height: 1.6; }
.hero-stats { display: flex; justify-content: center; gap: 48px; margin-top: 48px; flex-wrap: wrap; }
.hero-stat { text-align: center; }
.hero-stat .num { font-size: 36px; font-weight: 800; color: #2563EB; }
.hero-stat .label { font-size: 14px; color: #6B7280; margin-top: 4px; }
.hero-btns { display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; }

/* === Features Grid === */
.features-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.feature-card {
  background: #fff; border: 1px solid #E5E7EB; border-radius: 16px;
  padding: 36px 28px; text-align: center; transition: all .3s;
}
.feature-card:hover { transform: translateY(-4px); box-shadow: 0 12px 40px rgba(0,0,0,.08); border-color: #BFDBFE; }
.feature-icon { font-size: 42px; margin-bottom: 18px; }
.feature-card h3 { font-size: 20px; font-weight: 700; margin-bottom: 10px; }
.feature-card p { font-size: 15px; color: #6B7280; line-height: 1.6; }

/* === Section Title === */
.section-title { font-size: 36px; font-weight: 800; margin-bottom: 16px; }
.section-desc { font-size: 18px; color: #6B7280; max-width: 600px; margin: 0 auto 48px; }

/* === Pricing === */
.pricing-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.pricing-card {
  background: #fff; border: 2px solid #E5E7EB; border-radius: 16px;
  padding: 36px 24px; text-align: center; transition: all .3s; position: relative;
}
.pricing-card:hover { transform: translateY(-4px); box-shadow: 0 12px 40px rgba(0,0,0,.08); }
.pricing-card.popular { border-color: #2563EB; box-shadow: 0 8px 32px rgba(37,99,235,.15); }
.pricing-badge {
  position: absolute; top: -14px; left: 50%; transform: translateX(-50%);
  background: #2563EB; color: #fff; font-size: 13px; font-weight: 600;
  padding: 4px 20px; border-radius: 20px;
}
.pricing-card h3 { font-size: 22px; font-weight: 700; margin-bottom: 8px; }
.pricing-card .price { font-size: 42px; font-weight: 800; color: #2563EB; margin: 16px 0 4px; }
.pricing-card .price span { font-size: 16px; font-weight: 400; color: #6B7280; }
.pricing-card .price-note { font-size: 14px; color: #9CA3AF; margin-bottom: 24px; }
.pricing-card ul { text-align: left; margin-bottom: 28px; }
.pricing-card ul li { font-size: 14px; color: #4A4A6A; padding: 8px 0; border-bottom: 1px solid #F3F4F6; display: flex; align-items: center; gap: 8px; }
.pricing-card ul li::before { content: '\2713'; color: #2563EB; font-weight: 700; }

/* === Testimonials === */
.testimonials-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.testimonial-card {
  background: #fff; border: 1px solid #E5E7EB; border-radius: 16px;
  padding: 32px; transition: all .3s;
}
.testimonial-card:hover { box-shadow: 0 8px 32px rgba(0,0,0,.06); }
.testimonial-stars { color: #FBBF24; font-size: 18px; margin-bottom: 14px; }
.testimonial-text { font-size: 15px; color: #4A4A6A; line-height: 1.7; margin-bottom: 18px; font-style: italic; }
.testimonial-author { font-size: 14px; font-weight: 600; color: #1A1A2E; }
.testimonial-time { font-size: 13px; color: #9CA3AF; }

/* === FAQ === */
.faq-list { max-width: 800px; margin: 0 auto; }
.faq-item { border-bottom: 1px solid #E5E7EB; }
.faq-question {
  display: flex; justify-content: space-between; align-items: center;
  padding: 24px 0; font-size: 17px; font-weight: 600; cursor: default;
}
.faq-question::after { content: '+'; font-size: 24px; color: #2563EB; font-weight: 300; }
.faq-answer { padding: 0 0 24px; font-size: 15px; color: #4A4A6A; line-height: 1.8; }
.faq-answer ol { padding-left: 20px; margin-top: 8px; }
.faq-answer ol li { padding: 4px 0; list-style: decimal; }

/* === CTA Section === */
.cta-section {
  background: linear-gradient(135deg, #2563EB 0%, #1D4ED8 50%, #1E40AF 100%);
  padding: 80px 0; text-align: center; color: #fff;
}
.cta-section h2 { font-size: 36px; font-weight: 800; margin-bottom: 16px; }
.cta-section p { font-size: 18px; opacity: .9; margin-bottom: 36px; max-width: 500px; margin-left: auto; margin-right: auto; }

/* === Security === */
.security-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.security-card {
  background: #fff; border: 1px solid #E5E7EB; border-radius: 16px;
  padding: 32px; text-align: center; transition: all .3s;
}
.security-card:hover { box-shadow: 0 8px 32px rgba(0,0,0,.06); }
.security-icon { font-size: 40px; margin-bottom: 16px; }
.security-card h3 { font-size: 18px; font-weight: 700; margin-bottom: 8px; }
.security-card p { font-size: 14px; color: #6B7280; line-height: 1.6; }

/* === Footer === */
.site-footer { background: #0F172A; color: #CBD5E1; padding: 64px 0 32px; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 48px; margin-bottom: 48px; }
.footer-brand .logo { color: #fff; font-size: 22px; margin-bottom: 12px; display: inline-block; }
.footer-brand .logo span { color: #93C5FD; }
.footer-brand p { font-size: 14px; color: #94A3B8; line-height: 1.7; max-width: 320px; }
.footer-col h4 { font-size: 15px; font-weight: 700; color: #fff; margin-bottom: 18px; }
.footer-col a { display: block; font-size: 14px; color: #94A3B8; padding: 5px 0; transition: color .2s; }
.footer-col a:hover { color: #93C5FD; }
.footer-bottom { border-top: 1px solid #1E293B; padding-top: 24px; text-align: center; font-size: 13px; color: #64748B; }

/* === Page Header (inner pages) === */
.page-header {
  background: linear-gradient(135deg, #EFF6FF 0%, #DBEAFE 100%);
  padding: 80px 0 60px; text-align: center;
}
.page-header h1 { font-size: 42px; font-weight: 800; margin-bottom: 12px; }
.page-header p { font-size: 18px; color: #6B7280; max-width: 600px; margin: 0 auto; }

/* === Detail Content === */
.detail-row { display: flex; align-items: center; gap: 64px; margin-bottom: 64px; }
.detail-row.reverse { flex-direction: row-reverse; }
.detail-text { flex: 1; }
.detail-text h3 { font-size: 28px; font-weight: 700; margin-bottom: 16px; }
.detail-text p { font-size: 16px; color: #4A4A6A; line-height: 1.8; margin-bottom: 12px; }
.detail-visual { flex: 1; background: #F1F5F9; border-radius: 16px; padding: 40px; text-align: center; min-height: 280px; display: flex; align-items: center; justify-content: center; }
.detail-visual .icon-large { font-size: 80px; }

/* === About === */
.timeline { max-width: 700px; margin: 0 auto; position: relative; padding-left: 40px; }
.timeline::before { content: ''; position: absolute; left: 14px; top: 0; bottom: 0; width: 2px; background: #DBEAFE; }
.timeline-item { position: relative; margin-bottom: 36px; }
.timeline-item::before {
  content: ''; position: absolute; left: -33px; top: 6px;
  width: 14px; height: 14px; background: #2563EB; border-radius: 50%; border: 3px solid #DBEAFE;
}
.timeline-item h4 { font-size: 18px; font-weight: 700; margin-bottom: 6px; }
.timeline-item p { font-size: 15px; color: #6B7280; }

/* === Privacy === */
.prose { max-width: 800px; margin: 0 auto; }
.prose h2 { font-size: 24px; font-weight: 700; margin: 36px 0 16px; color: #1A1A2E; }
.prose p, .prose li { font-size: 15px; color: #4A4A6A; line-height: 1.8; margin-bottom: 12px; }
.prose ul { padding-left: 24px; }
.prose ul li { list-style: disc; }

/* === Help steps === */
.help-category { margin-bottom: 48px; }
.help-category h3 { font-size: 22px; font-weight: 700; margin-bottom: 20px; color: #2563EB; border-left: 4px solid #2563EB; padding-left: 16px; }
.step-list { padding-left: 0; counter-reset: step; }
.step-list li {
  counter-increment: step; position: relative; padding: 12px 0 12px 48px;
  font-size: 15px; color: #4A4A6A; line-height: 1.8; border-bottom: 1px solid #F3F4F6;
  list-style: none;
}
.step-list li::before {
  content: counter(step); position: absolute; left: 0; top: 12px;
  width: 32px; height: 32px; background: #EFF6FF; color: #2563EB;
  border-radius: 50%; display: flex; align-items: center; justify-content: center;
  font-size: 14px; font-weight: 700;
}

/* === Responsive === */
@media (max-width: 1024px) {
  .features-grid, .pricing-grid { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: repeat(2, 1fr); }
  .detail-row, .detail-row.reverse { flex-direction: column; }
}
@media (max-width: 768px) {
  .nav-links { display: none; }
  .mobile-menu-btn { display: block; }
  .hero h1 { font-size: 34px; }
  .hero .subtitle { font-size: 17px; }
  .hero-stats { gap: 24px; }
  .hero-stat .num { font-size: 28px; }
  .section-title { font-size: 28px; }
  .features-grid, .pricing-grid, .testimonials-grid, .security-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; gap: 32px; }
  .page-header h1 { font-size: 30px; }
  .section { padding: 56px 0; }
  .cta-section h2 { font-size: 28px; }
}