/* Feishu Official Website - Global Styles */
/* SEO-optimized, Bing-friendly */

/* Reset & Base */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { font-size: 16px; scroll-behavior: smooth; }
body {
    font-family: 'PingFang SC', 'Microsoft YaHei', 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    color: #1F2329;
    background: #FFFFFF;
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}
a { color: #3370FF; text-decoration: none; transition: color 0.15s ease; }
a:hover { color: #245bdb; }
img { max-width: 100%; height: auto; }
ul, ol { list-style: none; }

/* Container */
.container { max-width: 1200px; margin: 0 auto; padding: 0 24px; }

/* Header / Navigation */
.site-header {
    position: fixed; top: 0; left: 0; right: 0; z-index: 1000;
    background: rgba(255,255,255,0.92);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid rgba(0,0,0,0.06);
    height: 64px;
}
.header-inner {
    display: flex; align-items: center; justify-content: space-between;
    height: 64px; max-width: 1200px; margin: 0 auto; padding: 0 24px;
}
.logo { font-size: 24px; font-weight: 700; color: #3370FF; display: flex; align-items: center; gap: 8px; }
.logo svg { width: 32px; height: 32px; }
.main-nav { display: flex; gap: 32px; align-items: center; }
.main-nav a { color: #1F2329; font-size: 15px; font-weight: 500; padding: 8px 0; transition: color 0.15s; }
.main-nav a:hover { color: #3370FF; }
.header-cta { display: flex; gap: 12px; align-items: center; }

/* Buttons */
.btn {
    display: inline-flex; align-items: center; justify-content: center;
    padding: 10px 24px; border-radius: 8px; font-size: 15px; font-weight: 500;
    transition: all 0.15s ease; cursor: pointer; text-align: center;
}
.btn-primary {
    background: #3370FF; color: #FFFFFF; border: 1px solid #3370FF;
}
.btn-primary:hover { background: #245bdb; color: #FFFFFF; box-shadow: 0 4px 12px rgba(51,112,255,0.3); }
.btn-ghost {
    background: transparent; color: #3370FF; border: 1px solid #3370FF;
}
.btn-ghost:hover { background: rgba(51,112,255,0.06); color: #245bdb; }
.btn-large { padding: 14px 36px; font-size: 17px; border-radius: 8px; }

/* Hero Section */
.hero {
    padding: 160px 0 100px;
    background: linear-gradient(135deg, #f0f5ff 0%, #e8eeff 50%, #f5f0ff 100%);
    text-align: center; position: relative; overflow: hidden;
}
.hero-title { font-size: 56px; font-weight: 700; color: #1F2329; margin-bottom: 20px; line-height: 1.2; }
.hero-subtitle { font-size: 20px; color: #646A73; margin-bottom: 40px; max-width: 600px; margin-left: auto; margin-right: auto; }
.hero-cta { display: flex; gap: 16px; justify-content: center; align-items: center; flex-wrap: wrap; }
.hero-visual {
    margin-top: 60px; position: relative;
}
.hero-mockup {
    max-width: 900px; margin: 0 auto;
    background: rgba(255,255,255,0.8); border-radius: 16px;
    box-shadow: 0 20px 60px rgba(0,0,0,0.08);
    padding: 24px; backdrop-filter: blur(8px);
}

/* Section Common */
.section { padding: 100px 0; }
.section-alt { background: #F5F6F7; }
.section-title { font-size: 40px; font-weight: 700; text-align: center; margin-bottom: 16px; color: #1F2329; }
.section-desc { font-size: 18px; color: #646A73; text-align: center; max-width: 640px; margin: 0 auto 60px; }

/* Value Propositions */
.value-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.value-card {
    background: #FFFFFF; border-radius: 12px; padding: 32px 24px;
    box-shadow: 0 2px 12px rgba(0,0,0,0.04);
    transition: all 0.15s ease; text-align: center;
}
.value-card:hover { transform: translateY(-4px); box-shadow: 0 8px 24px rgba(0,0,0,0.08); }
.value-icon { font-size: 40px; margin-bottom: 16px; }
.value-card h3 { font-size: 18px; font-weight: 600; margin-bottom: 8px; }
.value-card p { font-size: 14px; color: #646A73; }

/* Product Showcase */
.product-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.product-card {
    background: #FFFFFF; border-radius: 12px; padding: 32px;
    border: 1px solid #e8e8e8; transition: all 0.15s ease;
}
.product-card:hover { border-color: #3370FF; box-shadow: 0 8px 24px rgba(0,0,0,0.08); transform: translateY(-2px); }
.product-card h3 { font-size: 20px; font-weight: 600; margin-bottom: 12px; color: #1F2329; }
.product-card p { font-size: 15px; color: #646A73; margin-bottom: 16px; }
.product-card .btn { font-size: 14px; padding: 8px 16px; }

/* AI Section */
.ai-section {
    background: linear-gradient(135deg, #1a1a3e 0%, #2d1b69 50%, #1a2a5e 100%);
    color: #FFFFFF; padding: 100px 0;
}
.ai-section .section-title { color: #FFFFFF; }
.ai-section .section-desc { color: rgba(255,255,255,0.7); }
.ai-demo {
    max-width: 700px; margin: 0 auto; background: rgba(255,255,255,0.08);
    border-radius: 16px; padding: 32px; border: 1px solid rgba(255,255,255,0.12);
}
.ai-chat-msg { margin-bottom: 16px; padding: 16px; border-radius: 12px; }
.ai-chat-user { background: rgba(51,112,255,0.2); text-align: right; }
.ai-chat-bot { background: rgba(123,92,252,0.15); }
.ai-chat-msg p { font-size: 15px; line-height: 1.7; }

/* Trust / Logo Wall */
.trust-logos {
    display: flex; flex-wrap: wrap; justify-content: center; gap: 40px; align-items: center;
    padding: 40px 0;
}
.trust-logo-item {
    font-size: 18px; font-weight: 600; color: #8F959E;
    transition: color 0.15s;
}
.trust-logo-item:hover { color: #1F2329; }
.trust-stat { text-align: center; margin-top: 40px; }
.trust-stat .number { font-size: 48px; font-weight: 700; color: #3370FF; }
.trust-stat .label { font-size: 16px; color: #646A73; margin-top: 8px; }

/* Solution Cards */
.solution-tabs { display: flex; justify-content: center; gap: 16px; margin-bottom: 40px; }
.solution-tab {
    padding: 10px 24px; border-radius: 8px; font-size: 15px; font-weight: 500;
    color: #646A73; border: 1px solid #e8e8e8; transition: all 0.15s;
}
.solution-tab:hover, .solution-tab.active { background: #3370FF; color: #FFFFFF; border-color: #3370FF; }
.solution-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.solution-card {
    background: #FFFFFF; border-radius: 12px; overflow: hidden;
    border: 1px solid #e8e8e8; transition: all 0.15s;
}
.solution-card:hover { box-shadow: 0 8px 24px rgba(0,0,0,0.08); transform: translateY(-2px); }
.solution-card-img {
    height: 180px; background: linear-gradient(135deg, #e8eeff, #f0f5ff);
    display: flex; align-items: center; justify-content: center; font-size: 48px;
}
.solution-card-body { padding: 24px; }
.solution-card-body h3 { font-size: 18px; font-weight: 600; margin-bottom: 8px; }
.solution-card-body p { font-size: 14px; color: #646A73; }

/* Security Section */
.security-badges { display: flex; justify-content: center; gap: 40px; flex-wrap: wrap; margin-bottom: 40px; }
.security-badge {
    text-align: center; padding: 24px;
}
.security-badge .badge-icon { font-size: 48px; margin-bottom: 12px; }
.security-badge .badge-label { font-size: 14px; font-weight: 600; color: #1F2329; }
.security-features { display: grid; grid-template-columns: repeat(2, 1fr); gap: 24px; max-width: 800px; margin: 0 auto; }
.security-feature { display: flex; gap: 12px; align-items: flex-start; }
.security-feature .icon { font-size: 24px; flex-shrink: 0; }
.security-feature h4 { font-size: 16px; font-weight: 600; margin-bottom: 4px; }
.security-feature p { font-size: 14px; color: #646A73; }

/* Pricing */
.pricing-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.pricing-card {
    background: #FFFFFF; border-radius: 12px; padding: 40px 32px;
    border: 1px solid #e8e8e8; text-align: center; transition: all 0.15s;
}
.pricing-card:hover { box-shadow: 0 8px 24px rgba(0,0,0,0.08); }
.pricing-card.featured { border-color: #3370FF; position: relative; }
.pricing-card.featured::before {
    content: '推荐'; position: absolute; top: -12px; left: 50%; transform: translateX(-50%);
    background: #3370FF; color: #FFF; padding: 4px 16px; border-radius: 12px; font-size: 12px;
}
.pricing-card h3 { font-size: 22px; font-weight: 600; margin-bottom: 8px; }
.pricing-price { font-size: 36px; font-weight: 700; color: #3370FF; margin-bottom: 24px; }
.pricing-price span { font-size: 14px; color: #646A73; font-weight: 400; }
.pricing-features { text-align: left; margin-bottom: 32px; }
.pricing-features li { padding: 8px 0; font-size: 14px; color: #646A73; border-bottom: 1px solid #f5f5f5; }
.pricing-features li::before { content: '✓ '; color: #3370FF; font-weight: 600; }

/* FAQ */
.faq-list { max-width: 800px; margin: 0 auto; }
.faq-item { border-bottom: 1px solid #e8e8e8; padding: 24px 0; }
.faq-item h3 { font-size: 17px; font-weight: 600; margin-bottom: 12px; color: #1F2329; }
.faq-item .faq-steps { padding-left: 0; }
.faq-item .faq-steps li {
    padding: 6px 0; font-size: 15px; color: #646A73; line-height: 1.7;
    counter-increment: step;
}
.faq-item .faq-steps { counter-reset: step; }
.faq-item .faq-steps li::before {
    content: '步骤' counter(step) '：'; font-weight: 600; color: #3370FF;
}

/* Footer CTA */
.footer-cta {
    background: linear-gradient(135deg, #3370FF 0%, #7B5CFC 100%);
    padding: 80px 0; text-align: center; color: #FFFFFF;
}
.footer-cta h2 { font-size: 36px; font-weight: 700; margin-bottom: 16px; }
.footer-cta p { font-size: 18px; opacity: 0.85; margin-bottom: 32px; }
.footer-cta .btn-primary { background: #FFFFFF; color: #3370FF; border-color: #FFFFFF; }
.footer-cta .btn-primary:hover { background: #f0f5ff; }
.footer-cta .btn-ghost { color: #FFFFFF; border-color: rgba(255,255,255,0.6); }
.footer-cta .btn-ghost:hover { background: rgba(255,255,255,0.1); color: #FFFFFF; }

/* Site Footer */
.site-footer { background: #1F2329; color: rgba(255,255,255,0.7); padding: 60px 0 30px; }
.footer-grid { display: grid; grid-template-columns: repeat(5, 1fr); gap: 32px; margin-bottom: 40px; }
.footer-col h4 { color: #FFFFFF; font-size: 15px; font-weight: 600; margin-bottom: 16px; }
.footer-col a { display: block; color: rgba(255,255,255,0.6); font-size: 14px; padding: 4px 0; transition: color 0.15s; }
.footer-col a:hover { color: #FFFFFF; }
.footer-bottom {
    border-top: 1px solid rgba(255,255,255,0.1); padding-top: 24px;
    display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: 16px;
}
.footer-bottom p { font-size: 13px; }
.footer-social { display: flex; gap: 16px; }
.footer-social a { color: rgba(255,255,255,0.6); font-size: 14px; }
.footer-social a:hover { color: #FFFFFF; }

/* Cases Page */
.case-card {
    background: #FFFFFF; border-radius: 12px; padding: 32px;
    border: 1px solid #e8e8e8; margin-bottom: 24px; transition: all 0.15s;
}
.case-card:hover { box-shadow: 0 8px 24px rgba(0,0,0,0.08); }
.case-quote { font-size: 17px; color: #1F2329; line-height: 1.8; margin-bottom: 20px; font-style: italic; }
.case-author { display: flex; align-items: center; gap: 12px; }
.case-avatar { width: 48px; height: 48px; border-radius: 50%; background: #e8eeff; display: flex; align-items: center; justify-content: center; font-size: 20px; }
.case-info .name { font-size: 15px; font-weight: 600; }
.case-info .title { font-size: 13px; color: #646A73; }

/* Blog */
.blog-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.blog-card {
    background: #FFFFFF; border-radius: 12px; overflow: hidden;
    border: 1px solid #e8e8e8; transition: all 0.15s;
}
.blog-card:hover { box-shadow: 0 8px 24px rgba(0,0,0,0.08); transform: translateY(-2px); }
.blog-card-img { height: 180px; background: linear-gradient(135deg, #e8eeff, #f5f0ff); display: flex; align-items: center; justify-content: center; font-size: 36px; }
.blog-card-body { padding: 24px; }
.blog-card-body h3 { font-size: 17px; font-weight: 600; margin-bottom: 8px; }
.blog-card-body p { font-size: 14px; color: #646A73; margin-bottom: 12px; }
.blog-card-body .date { font-size: 13px; color: #8F959E; }

/* Help Center */
.help-categories { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.help-category {
    background: #FFFFFF; border-radius: 12px; padding: 32px; text-align: center;
    border: 1px solid #e8e8e8; transition: all 0.15s;
}
.help-category:hover { box-shadow: 0 8px 24px rgba(0,0,0,0.08); border-color: #3370FF; }
.help-category .icon { font-size: 40px; margin-bottom: 16px; }
.help-category h3 { font-size: 18px; font-weight: 600; margin-bottom: 8px; }
.help-category p { font-size: 14px; color: #646A73; }

/* Sitemap HTML */
.sitemap-section { margin-bottom: 40px; }
.sitemap-section h2 { font-size: 22px; font-weight: 600; margin-bottom: 16px; padding-bottom: 8px; border-bottom: 2px solid #3370FF; }
.sitemap-links { display: grid; grid-template-columns: repeat(3, 1fr); gap: 8px; }
.sitemap-links a { font-size: 15px; padding: 8px 0; color: #3370FF; }
.sitemap-links a:hover { text-decoration: underline; }

/* Responsive */
@media (max-width: 1024px) {
    .value-grid { grid-template-columns: repeat(2, 1fr); }
    .product-grid { grid-template-columns: repeat(2, 1fr); }
    .solution-grid { grid-template-columns: repeat(2, 1fr); }
    .pricing-grid { grid-template-columns: repeat(2, 1fr); }
    .footer-grid { grid-template-columns: repeat(3, 1fr); }
}
@media (max-width: 768px) {
    .hero-title { font-size: 36px; }
    .hero-subtitle { font-size: 17px; }
    .section-title { font-size: 28px; }
    .section { padding: 60px 0; }
    .main-nav { display: none; }
    .value-grid { grid-template-columns: 1fr; }
    .product-grid { grid-template-columns: 1fr; }
    .solution-grid { grid-template-columns: 1fr; }
    .pricing-grid { grid-template-columns: 1fr; }
    .blog-grid { grid-template-columns: 1fr; }
    .help-categories { grid-template-columns: 1fr; }
    .footer-grid { grid-template-columns: repeat(2, 1fr); }
    .security-features { grid-template-columns: 1fr; }
    .sitemap-links { grid-template-columns: repeat(2, 1fr); }
    .hero { padding: 120px 0 60px; }
    .footer-cta h2 { font-size: 28px; }
}