/* === 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; }

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

/* === Header === */
.site-header {
    position: sticky; top: 0; z-index: 1000;
    background: rgba(255,255,255,.97); backdrop-filter: blur(10px);
    border-bottom: 1px solid #E8ECF1; 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: 700; color: #2563EB; display: flex; align-items: center; gap: 8px; }
.logo-icon { width: 36px; height: 36px; background: linear-gradient(135deg, #2563EB, #00C6FF); border-radius: 8px; display: flex; align-items: center; justify-content: center; color: #fff; font-size: 18px; font-weight: 800; }
.nav-links { display: flex; align-items: center; gap: 28px; }
.nav-links a { font-size: 15px; color: #4A4A6A; font-weight: 500; transition: color .2s; }
.nav-links a:hover { color: #2563EB; }
.nav-cta {
    display: inline-flex; align-items: center; padding: 10px 24px;
    background: linear-gradient(135deg, #2563EB, #1D4ED8); color: #fff !important;
    border-radius: 8px; font-weight: 600; font-size: 14px;
    transition: transform .2s, box-shadow .2s;
}
.nav-cta:hover { transform: translateY(-1px); box-shadow: 0 4px 15px rgba(37,99,235,.35); }
.mobile-toggle { display: none; background: none; border: none; font-size: 26px; cursor: pointer; color: #1A1A2E; }

/* === Hero === */
.hero {
    background: linear-gradient(135deg, #EFF6FF 0%, #DBEAFE 50%, #E0F2FE 100%);
    padding: 80px 20px 90px; text-align: center;
}
.hero h1 { font-size: 48px; font-weight: 800; color: #1A1A2E; margin-bottom: 16px; line-height: 1.2; }
.hero h1 span { color: #2563EB; }
.hero .subtitle { font-size: 18px; color: #4A4A6A; max-width: 680px; margin: 0 auto 32px; line-height: 1.7; }
.hero-stats { display: flex; justify-content: center; gap: 48px; margin-bottom: 40px; 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; justify-content: center; gap: 16px; flex-wrap: wrap; }
.btn-primary {
    display: inline-flex; align-items: center; gap: 8px;
    padding: 14px 36px; background: linear-gradient(135deg, #2563EB, #1D4ED8);
    color: #fff; border-radius: 10px; font-size: 16px; font-weight: 600;
    transition: transform .2s, box-shadow .2s;
}
.btn-primary:hover { 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: 16px; font-weight: 600;
    transition: background .2s, color .2s;
}
.btn-secondary:hover { background: #2563EB; color: #fff; }
.hero-badges { margin-top: 32px; display: flex; justify-content: center; gap: 24px; flex-wrap: wrap; }
.badge { display: inline-flex; align-items: center; gap: 6px; padding: 6px 16px; background: rgba(255,255,255,.8); border-radius: 20px; font-size: 13px; color: #4A4A6A; border: 1px solid #E5E7EB; }

/* === Section === */
.section { padding: 80px 20px; }
.section-alt { background: #F8FAFC; }
.section-dark { background: #0F172A; color: #fff; }
.section-title { text-align: center; margin-bottom: 56px; }
.section-title h2 { font-size: 36px; font-weight: 700; margin-bottom: 12px; }
.section-title p { font-size: 17px; color: #6B7280; max-width: 600px; margin: 0 auto; }
.section-dark .section-title p { color: #94A3B8; }

/* === Features Grid === */
.features-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; max-width: 1200px; margin: 0 auto; }
.feature-card {
    background: #fff; border-radius: 16px; padding: 36px 28px;
    border: 1px solid #E8ECF1; transition: transform .25s, box-shadow .25s;
    text-align: center;
}
.feature-card:hover { transform: translateY(-6px); box-shadow: 0 12px 40px rgba(0,0,0,.08); }
.feature-icon { font-size: 40px; margin-bottom: 16px; }
.feature-card h3 { font-size: 20px; font-weight: 600; margin-bottom: 10px; color: #1A1A2E; }
.feature-card p { font-size: 14px; color: #6B7280; line-height: 1.7; }

/* === Product Detail === */
.product-detail { display: flex; align-items: center; gap: 60px; max-width: 1200px; margin: 0 auto 60px; }
.product-detail:last-child { margin-bottom: 0; }
.product-detail.reverse { flex-direction: row-reverse; }
.product-text { flex: 1; }
.product-text h3 { font-size: 28px; font-weight: 700; margin-bottom: 16px; color: #1A1A2E; }
.product-text p { font-size: 16px; color: #4A4A6A; line-height: 1.8; margin-bottom: 16px; }
.product-visual { flex: 1; display: flex; justify-content: center; }
.product-mockup {
    width: 280px; height: 360px; background: linear-gradient(135deg, #EFF6FF, #DBEAFE);
    border-radius: 24px; display: flex; align-items: center; justify-content: center;
    font-size: 64px; border: 2px solid #E0E7FF;
}

/* === Pricing === */
.pricing-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; max-width: 1100px; margin: 0 auto; }
.pricing-card {
    background: #fff; border-radius: 16px; padding: 36px 24px;
    border: 2px solid #E8ECF1; text-align: center; position: relative;
    transition: transform .25s, box-shadow .25s;
}
.pricing-card:hover { transform: translateY(-4px); box-shadow: 0 8px 30px rgba(0,0,0,.08); }
.pricing-card.popular { border-color: #2563EB; }
.pricing-tag {
    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;
}
.pricing-card h3 { font-size: 22px; font-weight: 600; margin-bottom: 8px; }
.pricing-card .price { font-size: 40px; font-weight: 800; color: #2563EB; margin: 16px 0 4px; }
.pricing-card .price-unit { font-size: 14px; color: #6B7280; margin-bottom: 20px; }
.pricing-card .price small { font-size: 16px; font-weight: 400; }
.pricing-features { text-align: left; margin-bottom: 24px; }
.pricing-features li { padding: 8px 0; font-size: 14px; color: #4A4A6A; display: flex; align-items: center; gap: 8px; }
.pricing-features li::before { content: "\2713"; color: #22C55E; font-weight: 700; }
.pricing-btn {
    display: block; padding: 12px; border-radius: 8px; font-weight: 600; font-size: 15px;
    text-align: center; transition: background .2s;
}
.pricing-btn-outline { border: 2px solid #2563EB; color: #2563EB; }
.pricing-btn-outline:hover { background: #EFF6FF; }
.pricing-btn-fill { background: linear-gradient(135deg, #2563EB, #1D4ED8); color: #fff; }
.pricing-btn-fill:hover { box-shadow: 0 4px 15px rgba(37,99,235,.35); }

/* === Security === */
.security-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; max-width: 1100px; margin: 0 auto; }
.security-card {
    background: rgba(255,255,255,.05); border: 1px solid rgba(255,255,255,.1);
    border-radius: 16px; padding: 36px 28px; text-align: center;
}
.security-card .icon { font-size: 40px; margin-bottom: 16px; }
.security-card h3 { font-size: 18px; font-weight: 600; margin-bottom: 10px; }
.security-card p { font-size: 14px; color: #94A3B8; line-height: 1.7; }
.cert-badges { display: flex; justify-content: center; gap: 32px; margin-top: 48px; flex-wrap: wrap; }
.cert-badge {
    display: flex; align-items: center; gap: 10px;
    background: rgba(255,255,255,.06); border: 1px solid rgba(255,255,255,.12);
    border-radius: 12px; padding: 16px 28px;
}
.cert-badge .cert-icon { font-size: 28px; }
.cert-badge .cert-text { font-size: 14px; color: #CBD5E1; }
.cert-badge .cert-text strong { display: block; color: #fff; font-size: 15px; }

/* === Reviews === */
.reviews-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; max-width: 1100px; margin: 0 auto; }
.review-card {
    background: #fff; border-radius: 16px; padding: 32px;
    border: 1px solid #E8ECF1;
}
.review-stars { color: #FBBF24; font-size: 18px; margin-bottom: 12px; }
.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: 12px; color: #9CA3AF; }

/* === FAQ === */
.faq-list { max-width: 800px; margin: 0 auto; }
.faq-category { margin-bottom: 48px; }
.faq-category h3 { font-size: 22px; font-weight: 600; color: #2563EB; margin-bottom: 20px; padding-bottom: 10px; border-bottom: 2px solid #EFF6FF; }
.faq-item { border: 1px solid #E8ECF1; border-radius: 12px; margin-bottom: 12px; overflow: hidden; }
.faq-item summary {
    padding: 18px 24px; font-size: 16px; font-weight: 600; cursor: pointer;
    display: flex; align-items: center; justify-content: space-between;
    transition: background .2s; list-style: none;
}
.faq-item summary::-webkit-details-marker { display: none; }
.faq-item summary::after { content: "+"; font-size: 20px; color: #2563EB; font-weight: 300; transition: transform .2s; }
.faq-item[open] summary::after { content: "\2212"; }
.faq-item summary:hover { background: #F8FAFC; }
.faq-answer { 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; }
.faq-answer ol li { font-size: 15px; color: #4A4A6A; line-height: 1.8; margin-bottom: 6px; list-style: decimal; }

/* === CTA === */
.cta-section {
    background: linear-gradient(135deg, #2563EB, #1D4ED8);
    padding: 80px 20px; text-align: center; color: #fff;
}
.cta-section h2 { font-size: 36px; font-weight: 700; margin-bottom: 16px; }
.cta-section p { font-size: 17px; opacity: .9; margin-bottom: 32px; max-width: 500px; margin-left: auto; margin-right: auto; }
.btn-white {
    display: inline-flex; align-items: center; gap: 8px;
    padding: 16px 40px; background: #fff; color: #2563EB;
    border-radius: 10px; font-size: 17px; font-weight: 700;
    transition: transform .2s, box-shadow .2s;
}
.btn-white:hover { transform: translateY(-2px); box-shadow: 0 6px 20px rgba(0,0,0,.2); }

/* === Footer === */
.site-footer { background: #0F172A; color: #94A3B8; padding: 60px 20px 30px; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr 1fr; gap: 40px; max-width: 1200px; margin: 0 auto 40px; }
.footer-brand .logo { color: #fff; margin-bottom: 12px; }
.footer-brand p { font-size: 14px; line-height: 1.7; }
.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 {
    max-width: 1200px; margin: 0 auto; padding-top: 24px;
    border-top: 1px solid rgba(255,255,255,.08);
    display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: 12px;
    font-size: 13px;
}

/* === Page Header (inner pages) === */
.page-header {
    background: linear-gradient(135deg, #EFF6FF, #DBEAFE);
    padding: 60px 20px; text-align: center;
}
.page-header h1 { font-size: 40px; font-weight: 700; margin-bottom: 12px; }
.page-header p { font-size: 17px; color: #4A4A6A; max-width: 600px; margin: 0 auto; }

/* === Content Page === */
.content-page { max-width: 900px; margin: 0 auto; padding: 60px 20px; }
.content-page h2 { font-size: 24px; font-weight: 600; margin: 32px 0 16px; color: #1A1A2E; }
.content-page h3 { font-size: 20px; font-weight: 600; margin: 24px 0 12px; color: #1A1A2E; }
.content-page p { font-size: 16px; color: #4A4A6A; line-height: 1.8; margin-bottom: 16px; }
.content-page ul { padding-left: 20px; margin-bottom: 16px; }
.content-page ul li { font-size: 16px; color: #4A4A6A; line-height: 1.8; margin-bottom: 8px; list-style: disc; }
.content-page ol { padding-left: 20px; margin-bottom: 16px; }
.content-page ol li { font-size: 16px; color: #4A4A6A; line-height: 1.8; margin-bottom: 8px; list-style: decimal; }

/* === 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: 2px solid #E8ECF1; transition: border-color .2s, box-shadow .2s;
}
.download-card:hover { border-color: #2563EB; box-shadow: 0 8px 30px rgba(37,99,235,.1); }
.download-card .dl-icon { font-size: 48px; margin-bottom: 16px; }
.download-card h3 { font-size: 20px; font-weight: 600; margin-bottom: 8px; }
.download-card p { font-size: 14px; color: #6B7280; margin-bottom: 20px; }

/* === 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); }
    .reviews-grid { grid-template-columns: repeat(2, 1fr); }
    .footer-grid { grid-template-columns: repeat(3, 1fr); }
}
@media (max-width: 768px) {
    .nav-links { display: none; }
    .mobile-toggle { display: block; }
    .hero h1 { font-size: 32px; }
    .hero .subtitle { font-size: 16px; }
    .hero-stats { gap: 24px; }
    .hero-stat .num { font-size: 28px; }
    .features-grid { grid-template-columns: 1fr; }
    .pricing-grid { grid-template-columns: 1fr; }
    .security-grid { grid-template-columns: 1fr; }
    .reviews-grid { grid-template-columns: 1fr; }
    .product-detail, .product-detail.reverse { flex-direction: column; }
    .footer-grid { grid-template-columns: 1fr 1fr; }
    .section-title h2 { font-size: 28px; }
    .download-grid { grid-template-columns: 1fr; }
    .page-header h1 { font-size: 30px; }
}
@media (max-width: 480px) {
    .hero-btns { flex-direction: column; align-items: center; }
    .footer-grid { grid-template-columns: 1fr; }
    .footer-bottom { flex-direction: column; text-align: center; }
}