/* === 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', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif; color: #1a1a2e; line-height: 1.6; background: #fff; }
a { text-decoration: none; color: inherit; transition: color .2s; }
ul, ol { list-style: none; }
img { max-width: 100%; display: block; }
.container { max-width: 1200px; margin: 0 auto; padding: 0 20px; }

/* === Header === */
.header { position: sticky; top: 0; z-index: 1000; background: rgba(255,255,255,.97); backdrop-filter: blur(10px); border-bottom: 1px solid #e8ecf1; }
.header .container { display: flex; align-items: center; justify-content: space-between; height: 72px; }
.logo { display: flex; align-items: center; gap: 10px; font-size: 22px; font-weight: 700; color: #2563eb; }
.logo-icon { width: 36px; height: 36px; background: linear-gradient(135deg, #2563eb, #00c6ff); border-radius: 10px; display: flex; align-items: center; justify-content: center; color: #fff; font-weight: 800; font-size: 18px; }
.nav { display: flex; align-items: center; gap: 32px; }
.nav a { font-size: 15px; color: #4a4a6a; font-weight: 500; transition: color .2s; }
.nav a:hover { color: #2563eb; }
.nav-right { display: flex; align-items: center; gap: 16px; }
.btn { display: inline-flex; align-items: center; justify-content: center; padding: 10px 24px; border-radius: 8px; font-size: 15px; font-weight: 600; transition: all .25s; cursor: pointer; border: none; }
.btn-primary { background: linear-gradient(135deg, #2563eb, #1d4ed8); color: #fff; box-shadow: 0 4px 14px rgba(37,99,235,.35); }
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 6px 20px rgba(37,99,235,.45); }
.btn-outline { border: 2px solid #2563eb; color: #2563eb; background: transparent; }
.btn-outline:hover { background: #2563eb; color: #fff; }
.btn-lg { padding: 14px 36px; font-size: 17px; border-radius: 10px; }
.btn-sm { padding: 8px 18px; font-size: 14px; }
.mobile-menu-btn { display: none; background: none; border: none; font-size: 28px; color: #1a1a2e; cursor: pointer; }

/* === Hero === */
.hero { background: linear-gradient(160deg, #f0f5ff 0%, #e8f0fe 40%, #fff 100%); padding: 100px 0 80px; position: relative; overflow: hidden; }
.hero::before { content: ''; position: absolute; top: -200px; right: -200px; width: 600px; height: 600px; background: radial-gradient(circle, rgba(37,99,235,.08) 0%, transparent 70%); border-radius: 50%; }
.hero .container { display: flex; align-items: center; gap: 60px; position: relative; z-index: 1; }
.hero-text { flex: 1; }
.hero-badge { display: inline-flex; align-items: center; gap: 8px; background: rgba(37,99,235,.08); color: #2563eb; padding: 6px 16px; border-radius: 20px; font-size: 14px; font-weight: 600; margin-bottom: 24px; }
.hero h1 { font-size: 52px; font-weight: 800; line-height: 1.2; margin-bottom: 20px; color: #0f172a; }
.hero h1 span { color: #2563eb; }
.hero-subtitle { font-size: 18px; color: #4a4a6a; line-height: 1.8; margin-bottom: 32px; max-width: 520px; }
.hero-stats { display: flex; gap: 40px; margin-bottom: 36px; }
.hero-stat { text-align: center; }
.hero-stat .num { font-size: 32px; font-weight: 800; color: #2563eb; }
.hero-stat .label { font-size: 13px; color: #6b7280; margin-top: 4px; }
.hero-actions { display: flex; gap: 16px; flex-wrap: wrap; }
.hero-visual { flex: 1; display: flex; justify-content: center; }
.hero-mockup { width: 320px; height: 440px; background: linear-gradient(135deg, #1e3a5f, #2563eb); border-radius: 30px; padding: 20px; box-shadow: 0 30px 60px rgba(37,99,235,.25); position: relative; }
.mockup-screen { width: 100%; height: 100%; background: linear-gradient(180deg, #0f172a 0%, #1e293b 100%); border-radius: 18px; display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 20px; }
.mockup-logo { width: 60px; height: 60px; background: linear-gradient(135deg, #2563eb, #00c6ff); border-radius: 16px; display: flex; align-items: center; justify-content: center; color: #fff; font-size: 24px; font-weight: 800; }
.mockup-text { color: #94a3b8; font-size: 14px; }
.mockup-btn { background: linear-gradient(135deg, #2563eb, #1d4ed8); color: #fff; padding: 12px 40px; border-radius: 25px; font-size: 15px; font-weight: 600; }
.mockup-status { color: #22c55e; font-size: 13px; display: flex; align-items: center; gap: 6px; }
.mockup-dot { width: 8px; height: 8px; background: #22c55e; border-radius: 50%; }

/* === Section Common === */
.section { padding: 80px 0; }
.section-alt { background: #f8fafc; }
.section-dark { background: linear-gradient(135deg, #0f172a, #1e293b); color: #fff; }
.section-header { text-align: center; margin-bottom: 60px; }
.section-header h2 { font-size: 36px; font-weight: 800; margin-bottom: 16px; color: #0f172a; }
.section-dark .section-header h2 { color: #fff; }
.section-header p { font-size: 17px; color: #6b7280; max-width: 600px; margin: 0 auto; }
.section-dark .section-header p { color: #94a3b8; }

/* === Features Grid === */
.features-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.feature-card { background: #fff; border: 1px solid #e8ecf1; border-radius: 16px; padding: 36px 28px; text-align: center; transition: all .3s; }
.feature-card:hover { transform: translateY(-6px); box-shadow: 0 20px 40px rgba(0,0,0,.08); border-color: #2563eb; }
.feature-icon { width: 64px; height: 64px; margin: 0 auto 20px; background: linear-gradient(135deg, #eff6ff, #dbeafe); border-radius: 16px; display: flex; align-items: center; justify-content: center; font-size: 28px; }
.feature-card h3 { font-size: 18px; font-weight: 700; margin-bottom: 10px; }
.feature-card p { font-size: 14px; color: #6b7280; line-height: 1.7; }

/* === Product Detail === */
.detail-block { display: flex; align-items: center; gap: 60px; margin-bottom: 80px; }
.detail-block:nth-child(even) { flex-direction: row-reverse; }
.detail-block:last-child { margin-bottom: 0; }
.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: 16px; }
.detail-visual { flex: 1; display: flex; justify-content: center; }
.detail-img-box { width: 100%; max-width: 400px; height: 280px; background: linear-gradient(135deg, #eff6ff, #dbeafe); border-radius: 20px; display: flex; align-items: center; justify-content: center; font-size: 48px; }

/* === Pricing === */
.pricing-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.pricing-card { background: #fff; border: 2px solid #e8ecf1; border-radius: 20px; padding: 36px 28px; text-align: center; transition: all .3s; position: relative; }
.pricing-card:hover { transform: translateY(-4px); box-shadow: 0 16px 40px rgba(0,0,0,.08); }
.pricing-card.popular { border-color: #2563eb; box-shadow: 0 16px 40px rgba(37,99,235,.15); }
.pricing-badge { position: absolute; top: -14px; left: 50%; transform: translateX(-50%); background: linear-gradient(135deg, #2563eb, #1d4ed8); color: #fff; padding: 4px 20px; border-radius: 20px; font-size: 13px; font-weight: 600; white-space: nowrap; }
.pricing-card h3 { font-size: 20px; font-weight: 700; margin-bottom: 8px; }
.pricing-price { font-size: 42px; font-weight: 800; color: #2563eb; margin: 16px 0; }
.pricing-price span { font-size: 16px; color: #6b7280; font-weight: 400; }
.pricing-features { margin: 24px 0; text-align: left; }
.pricing-features li { padding: 8px 0; font-size: 14px; color: #4a4a6a; display: flex; align-items: center; gap: 10px; }
.pricing-features li::before { content: '\2713'; color: #22c55e; font-weight: 700; }

/* === Security === */
.security-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.security-card { background: rgba(255,255,255,.05); border: 1px solid rgba(255,255,255,.1); border-radius: 16px; padding: 32px; text-align: center; }
.security-card .icon { font-size: 40px; margin-bottom: 16px; }
.security-card h3 { font-size: 18px; font-weight: 700; margin-bottom: 10px; }
.security-card p { font-size: 14px; color: #94a3b8; line-height: 1.7; }
.cert-badges { display: flex; justify-content: center; gap: 40px; margin-top: 48px; flex-wrap: wrap; }
.cert-badge { display: flex; align-items: center; gap: 12px; background: rgba(255,255,255,.05); border: 1px solid rgba(255,255,255,.1); padding: 16px 28px; border-radius: 12px; }
.cert-badge .icon { font-size: 28px; }
.cert-badge span { font-size: 14px; color: #cbd5e1; }

/* === Testimonials === */
.testimonials-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.testimonial-card { background: #fff; border: 1px solid #e8ecf1; border-radius: 16px; padding: 32px; }
.testimonial-stars { color: #f59e0b; font-size: 18px; margin-bottom: 16px; }
.testimonial-text { font-size: 15px; color: #4a4a6a; line-height: 1.8; margin-bottom: 20px; font-style: italic; }
.testimonial-author { font-size: 14px; font-weight: 600; color: #0f172a; }
.testimonial-date { font-size: 12px; color: #9ca3af; margin-top: 4px; }

/* === FAQ === */
.faq-list { max-width: 800px; margin: 0 auto; }
.faq-item { border: 1px solid #e8ecf1; border-radius: 12px; margin-bottom: 12px; overflow: hidden; }
.faq-question { display: flex; align-items: center; justify-content: space-between; padding: 20px 24px; font-size: 16px; font-weight: 600; cursor: pointer; background: #fff; transition: background .2s; }
.faq-question:hover { background: #f8fafc; }
.faq-question .arrow { font-size: 20px; color: #9ca3af; transition: transform .3s; }
.faq-answer { padding: 0 24px 20px; font-size: 15px; color: #4a4a6a; line-height: 1.8; }
.faq-answer ol { padding-left: 20px; }
.faq-answer ol li { margin-bottom: 8px; list-style: decimal; }

/* === CTA Bottom === */
.cta-bottom { background: linear-gradient(135deg, #2563eb, #1d4ed8); padding: 80px 0; text-align: center; color: #fff; }
.cta-bottom h2 { font-size: 36px; font-weight: 800; margin-bottom: 16px; }
.cta-bottom p { font-size: 17px; opacity: .9; margin-bottom: 32px; max-width: 500px; margin-left: auto; margin-right: auto; }
.cta-bottom .btn { background: #fff; color: #2563eb; font-weight: 700; }
.cta-bottom .btn:hover { transform: translateY(-2px); box-shadow: 0 8px 24px rgba(0,0,0,.2); }

/* === Footer === */
.footer { background: #0f172a; color: #94a3b8; padding: 60px 0 30px; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 40px; margin-bottom: 40px; }
.footer-brand .logo { color: #fff; margin-bottom: 16px; }
.footer-brand p { font-size: 14px; line-height: 1.7; max-width: 300px; }
.footer-col h4 { color: #fff; font-size: 15px; font-weight: 600; margin-bottom: 16px; }
.footer-col a { display: block; font-size: 14px; color: #94a3b8; padding: 4px 0; transition: color .2s; }
.footer-col a:hover { color: #fff; }
.footer-bottom { border-top: 1px solid rgba(255,255,255,.08); padding-top: 24px; display: flex; justify-content: space-between; align-items: center; font-size: 13px; }
.footer-certs { display: flex; gap: 16px; align-items: center; }
.footer-cert { background: rgba(255,255,255,.05); padding: 6px 14px; border-radius: 6px; font-size: 12px; }

/* === Sub Pages === */
.page-hero { background: linear-gradient(160deg, #f0f5ff, #e8f0fe); padding: 60px 0; text-align: center; }
.page-hero h1 { font-size: 40px; font-weight: 800; color: #0f172a; margin-bottom: 12px; }
.page-hero p { font-size: 17px; color: #6b7280; }
.content-block { padding: 60px 0; }
.content-block h2 { font-size: 28px; font-weight: 700; margin-bottom: 20px; color: #0f172a; }
.content-block h3 { font-size: 22px; font-weight: 600; margin: 24px 0 12px; color: #1e293b; }
.content-block p { font-size: 16px; color: #4a4a6a; line-height: 1.8; margin-bottom: 16px; }
.content-block ul { margin-bottom: 16px; }
.content-block ul li { padding: 6px 0; font-size: 15px; color: #4a4a6a; display: flex; align-items: flex-start; gap: 10px; }
.content-block ul li::before { content: '\2022'; color: #2563eb; font-weight: 700; flex-shrink: 0; }

/* === 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: 2px solid #e8ecf1; border-radius: 16px; padding: 36px; text-align: center; transition: all .3s; }
.download-card:hover { border-color: #2563eb; box-shadow: 0 12px 30px rgba(37,99,235,.1); }
.download-card .icon { font-size: 48px; margin-bottom: 16px; }
.download-card h3 { font-size: 20px; font-weight: 700; margin-bottom: 8px; }
.download-card p { font-size: 14px; color: #6b7280; margin-bottom: 20px; }

/* === Help Page === */
.help-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 24px; }
.help-card { background: #fff; border: 1px solid #e8ecf1; border-radius: 16px; padding: 32px; }
.help-card h3 { font-size: 18px; font-weight: 700; margin-bottom: 16px; color: #0f172a; display: flex; align-items: center; gap: 10px; }
.help-card .step { margin-bottom: 12px; padding-left: 8px; }
.help-card .step-num { display: inline-flex; align-items: center; justify-content: center; width: 24px; height: 24px; background: #2563eb; color: #fff; border-radius: 50%; font-size: 12px; font-weight: 700; margin-right: 8px; flex-shrink: 0; }
.help-card .step-text { font-size: 14px; color: #4a4a6a; line-height: 1.7; }

/* === About Page === */
.about-story { display: flex; gap: 60px; align-items: center; margin-bottom: 60px; }
.about-story-text { flex: 1; }
.about-story-visual { flex: 1; }
.about-visual-box { width: 100%; height: 300px; background: linear-gradient(135deg, #eff6ff, #dbeafe); border-radius: 20px; display: flex; align-items: center; justify-content: center; font-size: 64px; }
.timeline { position: relative; padding-left: 40px; }
.timeline::before { content: ''; position: absolute; left: 15px; top: 0; bottom: 0; width: 2px; background: #e8ecf1; }
.timeline-item { position: relative; margin-bottom: 32px; }
.timeline-item::before { content: ''; position: absolute; left: -32px; top: 6px; width: 12px; height: 12px; background: #2563eb; border-radius: 50%; }
.timeline-item h4 { font-size: 16px; font-weight: 700; color: #0f172a; }
.timeline-item p { font-size: 14px; color: #6b7280; margin-top: 4px; }

/* === Responsive === */
@media (max-width: 1024px) {
  .features-grid { grid-template-columns: repeat(2, 1fr); }
  .pricing-grid { grid-template-columns: repeat(2, 1fr); }
  .security-grid { grid-template-columns: repeat(2, 1fr); }
  .testimonials-grid { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 768px) {
  .nav { display: none; }
  .mobile-menu-btn { display: block; }
  .hero .container { flex-direction: column; text-align: center; }
  .hero h1 { font-size: 36px; }
  .hero-subtitle { margin: 0 auto 32px; }
  .hero-stats { justify-content: center; }
  .hero-actions { justify-content: center; }
  .hero-visual { order: -1; }
  .hero-mockup { width: 240px; height: 340px; }
  .features-grid { grid-template-columns: 1fr; }
  .pricing-grid { grid-template-columns: 1fr; }
  .security-grid { grid-template-columns: 1fr; }
  .testimonials-grid { grid-template-columns: 1fr; }
  .detail-block, .detail-block:nth-child(even) { flex-direction: column; }
  .about-story { flex-direction: column; }
  .footer-grid { grid-template-columns: 1fr; }
  .footer-bottom { flex-direction: column; gap: 16px; text-align: center; }
  .download-grid { grid-template-columns: 1fr; }
  .help-grid { grid-template-columns: 1fr; }
  .section-header h2 { font-size: 28px; }
  .page-hero h1 { font-size: 30px; }
  .hero-stats { gap: 20px; }
  .hero-stat .num { font-size: 24px; }
}