/* === 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: #333; background: #fff; line-height: 1.6; }
a { text-decoration: none; color: inherit; transition: color .2s; }
img { max-width: 100%; display: block; }
ul, ol { list-style: none; }

/* === Container === */
.container { max-width: 1200px; margin: 0 auto; padding: 0 20px; }

/* === Navigation === */
.navbar { position: fixed; top: 0; left: 0; right: 0; z-index: 1000; background: rgba(255,255,255,.97); border-bottom: 1px solid #e8edf3; backdrop-filter: blur(10px); height: 64px; }
.navbar .container { display: flex; align-items: center; justify-content: space-between; height: 100%; }
.nav-logo { font-size: 22px; font-weight: 700; color: #2563eb; letter-spacing: -0.5px; }
.nav-logo span { color: #1e40af; }
.nav-links { display: flex; align-items: center; gap: 32px; }
.nav-links a { font-size: 15px; color: #475569; font-weight: 500; transition: color .2s; }
.nav-links a:hover { color: #2563eb; }
.nav-cta { display: inline-flex; align-items: center; padding: 8px 20px; background: #2563eb; color: #fff !important; border-radius: 8px; font-size: 14px; font-weight: 600; transition: background .2s, transform .1s; }
.nav-cta:hover { background: #1d4ed8; transform: translateY(-1px); }

/* Mobile menu toggle */
.nav-toggle { display: none; flex-direction: column; gap: 5px; cursor: pointer; padding: 5px; }
.nav-toggle span { width: 24px; height: 2px; background: #333; border-radius: 2px; transition: .3s; }

/* === Hero === */
.hero { padding: 140px 0 80px; background: linear-gradient(135deg, #eff6ff 0%, #dbeafe 50%, #e0e7ff 100%); text-align: center; min-height: 100vh; display: flex; align-items: center; }
.hero-inner { max-width: 800px; margin: 0 auto; }
.hero-badge { display: inline-block; padding: 6px 16px; background: rgba(37,99,235,.1); color: #2563eb; border-radius: 20px; font-size: 14px; font-weight: 600; margin-bottom: 24px; }
.hero h1 { font-size: 48px; font-weight: 800; color: #0f172a; line-height: 1.2; margin-bottom: 20px; }
.hero h1 em { font-style: normal; color: #2563eb; }
.hero p { font-size: 20px; color: #475569; margin-bottom: 12px; max-width: 600px; margin-left: auto; margin-right: auto; }
.hero-stats { font-size: 15px; color: #64748b; margin-bottom: 36px; }
.hero-stats strong { color: #2563eb; }
.hero-btns { display: flex; justify-content: center; gap: 16px; margin-bottom: 40px; flex-wrap: wrap; }
.btn-primary { display: inline-flex; align-items: center; gap: 8px; padding: 14px 36px; background: #2563eb; color: #fff; border-radius: 10px; font-size: 17px; font-weight: 600; transition: background .2s, transform .1s, 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-flex; align-items: center; gap: 8px; padding: 14px 36px; background: #fff; color: #2563eb; border: 2px solid #2563eb; border-radius: 10px; font-size: 17px; font-weight: 600; transition: background .2s, transform .1s; }
.btn-secondary:hover { background: #eff6ff; transform: translateY(-2px); }
.hero-platforms { display: flex; justify-content: center; gap: 32px; flex-wrap: wrap; }
.hero-platforms .platform-item { display: flex; flex-direction: column; align-items: center; gap: 6px; color: #64748b; font-size: 13px; }
.platform-icon { width: 40px; height: 40px; background: #fff; border-radius: 10px; display: flex; align-items: center; justify-content: center; box-shadow: 0 2px 8px rgba(0,0,0,.06); font-size: 20px; }

/* === Section Common === */
.section { padding: 80px 0; }
.section-alt { background: #f8fafc; }
.section-title { text-align: center; margin-bottom: 56px; }
.section-title h2 { font-size: 36px; font-weight: 700; color: #0f172a; margin-bottom: 12px; }
.section-title p { font-size: 17px; color: #64748b; max-width: 560px; margin: 0 auto; }

/* === Features === */
.features-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.feature-card { background: #fff; border: 1px solid #e2e8f0; border-radius: 14px; padding: 32px 28px; transition: transform .2s, box-shadow .2s, border-color .2s; }
.feature-card:hover { transform: translateY(-4px); box-shadow: 0 12px 32px rgba(0,0,0,.08); border-color: #bfdbfe; }
.feature-icon { width: 52px; height: 52px; background: linear-gradient(135deg, #dbeafe, #eff6ff); border-radius: 12px; display: flex; align-items: center; justify-content: center; font-size: 24px; margin-bottom: 18px; }
.feature-card h3 { font-size: 20px; font-weight: 600; color: #0f172a; margin-bottom: 10px; }
.feature-card p { font-size: 15px; color: #64748b; line-height: 1.7; }

/* === Download Section === */
.download-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.download-card { background: #fff; border: 1px solid #e2e8f0; border-radius: 14px; padding: 36px 24px; text-align: center; transition: transform .2s, box-shadow .2s, border-color .2s; }
.download-card:hover { transform: translateY(-4px); box-shadow: 0 12px 32px rgba(0,0,0,.08); border-color: #bfdbfe; }
.download-card .dl-icon { width: 64px; height: 64px; margin: 0 auto 18px; background: linear-gradient(135deg, #dbeafe, #eff6ff); border-radius: 16px; display: flex; align-items: center; justify-content: center; font-size: 30px; }
.download-card h3 { font-size: 20px; font-weight: 600; color: #0f172a; margin-bottom: 6px; }
.download-card .dl-ver { font-size: 13px; color: #94a3b8; margin-bottom: 18px; }
.download-card .dl-btn { display: inline-block; padding: 10px 28px; background: #2563eb; color: #fff; border-radius: 8px; font-size: 15px; font-weight: 600; transition: background .2s, transform .1s; }
.download-card .dl-btn:hover { background: #1d4ed8; transform: translateY(-1px); }

/* === Trust Section === */
.trust-section { background: linear-gradient(135deg, #0f172a 0%, #1e293b 100%); color: #fff; padding: 64px 0; }
.trust-inner { display: flex; align-items: center; gap: 48px; flex-wrap: wrap; }
.trust-badge { flex: 0 0 auto; }
.trust-badge-icon { width: 72px; height: 72px; background: rgba(37,99,235,.2); border-radius: 50%; display: flex; align-items: center; justify-content: center; font-size: 32px; margin-bottom: 12px; }
.trust-badge h3 { font-size: 20px; font-weight: 700; }
.trust-badge p { font-size: 14px; color: #94a3b8; }
.trust-items { flex: 1; display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.trust-item { padding: 20px; background: rgba(255,255,255,.05); border-radius: 10px; border: 1px solid rgba(255,255,255,.08); }
.trust-item h4 { font-size: 16px; font-weight: 600; margin-bottom: 6px; color: #93c5fd; }
.trust-item p { font-size: 14px; color: #94a3b8; line-height: 1.6; }
.trust-warning { margin-top: 24px; padding: 14px 20px; background: rgba(245,158,11,.1); border: 1px solid rgba(245,158,11,.3); border-radius: 8px; color: #fbbf24; font-size: 14px; text-align: center; }

/* === FAQ === */
.faq-list { max-width: 860px; margin: 0 auto; }
.faq-item { border: 1px solid #e2e8f0; border-radius: 12px; margin-bottom: 16px; overflow: hidden; background: #fff; }
.faq-item h3 { font-size: 18px; font-weight: 600; color: #0f172a; padding: 20px 24px; background: #f8fafc; border-bottom: 1px solid #e2e8f0; }
.faq-answer { padding: 20px 24px; }
.faq-answer p { font-size: 15px; color: #475569; margin-bottom: 14px; line-height: 1.7; }
.faq-answer ol { padding-left: 0; counter-reset: step; }
.faq-answer ol li { counter-increment: step; position: relative; padding: 8px 0 8px 36px; font-size: 15px; color: #475569; line-height: 1.7; }
.faq-answer ol li::before { content: counter(step); position: absolute; left: 0; top: 8px; width: 24px; height: 24px; background: #2563eb; color: #fff; border-radius: 50%; font-size: 12px; font-weight: 700; display: flex; align-items: center; justify-content: center; }

/* === Guide Page === */
.page-header { padding: 120px 0 60px; background: linear-gradient(135deg, #eff6ff 0%, #dbeafe 100%); text-align: center; }
.page-header h1 { font-size: 40px; font-weight: 800; color: #0f172a; margin-bottom: 12px; }
.page-header p { font-size: 18px; color: #475569; }
.guide-steps { max-width: 800px; margin: 0 auto; }
.guide-step { display: flex; gap: 24px; margin-bottom: 40px; padding: 28px; background: #fff; border: 1px solid #e2e8f0; border-radius: 14px; transition: box-shadow .2s; }
.guide-step:hover { box-shadow: 0 8px 24px rgba(0,0,0,.06); }
.guide-step-num { flex: 0 0 48px; width: 48px; height: 48px; background: #2563eb; color: #fff; border-radius: 50%; display: flex; align-items: center; justify-content: center; font-size: 20px; font-weight: 700; }
.guide-step-content h3 { font-size: 20px; font-weight: 600; color: #0f172a; margin-bottom: 8px; }
.guide-step-content p { font-size: 15px; color: #64748b; line-height: 1.7; }

/* === Footer === */
.footer { background: #0f172a; color: #94a3b8; padding: 48px 0 28px; }
.footer-inner { display: flex; justify-content: space-between; align-items: flex-start; gap: 40px; flex-wrap: wrap; margin-bottom: 32px; }
.footer-brand { max-width: 320px; }
.footer-brand .nav-logo { margin-bottom: 12px; display: inline-block; }
.footer-brand p { font-size: 14px; line-height: 1.7; }
.footer-links { display: flex; gap: 56px; }
.footer-col h4 { font-size: 15px; font-weight: 600; color: #e2e8f0; margin-bottom: 14px; }
.footer-col a { display: block; font-size: 14px; color: #94a3b8; margin-bottom: 10px; transition: color .2s; }
.footer-col a:hover { color: #93c5fd; }
.footer-bottom { border-top: 1px solid rgba(255,255,255,.08); padding-top: 24px; display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: 12px; font-size: 13px; }
.footer-official { color: #fbbf24; font-size: 13px; }

/* === Responsive === */
@media (max-width: 1024px) {
  .features-grid { grid-template-columns: repeat(2, 1fr); }
  .download-grid { grid-template-columns: repeat(2, 1fr); }
  .trust-items { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 768px) {
  .nav-links { display: none; }
  .nav-toggle { display: flex; }
  .nav-links.active { display: flex; flex-direction: column; position: absolute; top: 64px; left: 0; right: 0; background: #fff; padding: 20px; border-bottom: 1px solid #e2e8f0; box-shadow: 0 8px 24px rgba(0,0,0,.08); }
  .hero { padding: 100px 0 60px; min-height: auto; }
  .hero h1 { font-size: 32px; }
  .hero p { font-size: 17px; }
  .hero-btns { flex-direction: column; align-items: center; }
  .hero-platforms { gap: 20px; }
  .features-grid { grid-template-columns: 1fr; }
  .download-grid { grid-template-columns: repeat(2, 1fr); }
  .trust-inner { flex-direction: column; text-align: center; }
  .trust-items { grid-template-columns: 1fr; }
  .section-title h2 { font-size: 28px; }
  .section { padding: 56px 0; }
  .footer-inner { flex-direction: column; }
  .footer-links { flex-direction: column; gap: 28px; }
  .footer-bottom { flex-direction: column; text-align: center; }
  .guide-step { flex-direction: column; gap: 12px; }
  .page-header h1 { font-size: 30px; }
}
@media (max-width: 480px) {
  .download-grid { grid-template-columns: 1fr; }
  .hero h1 { font-size: 28px; }
}