*{margin:0;padding:0;box-sizing:border-box}
body{font-family:-apple-system,BlinkMacSystemFont,'Segoe UI','PingFang SC','Microsoft YaHei',sans-serif;color:#1c1e21;background:#fff;line-height:1.5;-webkit-font-smoothing:antialiased}
a{text-decoration:none;color:inherit}
a:hover{text-decoration:none}
img{max-width:100%;height:auto}
ul{list-style:none}
.container{max-width:1100px;margin:0 auto;padding:0 20px}

/* Header */
.header{position:fixed;top:0;left:0;right:0;z-index:1000;background:#fff;border-bottom:1px solid #e9edef;height:64px}
.header-inner{max-width:1100px;margin:0 auto;padding:0 20px;display:flex;align-items:center;justify-content:space-between;height:64px}
.header-logo{display:flex;align-items:center;gap:8px;flex-shrink:0}
.header-logo img{height:36px;display:block}
.header-logo span{font-size:18px;font-weight:600;color:#111b21;white-space:nowrap}
.header-nav{display:flex;align-items:center;gap:4px}
.header-nav a,.header-nav .nav-dropdown-trigger{padding:8px 14px;font-size:14px;color:#667781;border-radius:24px;transition:background .2s,color .2s;cursor:pointer;position:relative;white-space:nowrap}
.header-nav a:hover,.header-nav .nav-dropdown-trigger:hover{background:#f0f2f5;color:#111b21}
.header-nav .nav-dropdown-trigger{display:flex;align-items:center;gap:4px}
.header-nav .nav-dropdown-trigger .arrow{font-size:10px;margin-left:2px}
.header-nav .dropdown-menu{display:none;position:absolute;top:100%;left:0;background:#fff;border:1px solid #e9edef;border-radius:12px;box-shadow:0 12px 28px rgba(0,0,0,.08);padding:8px 0;min-width:180px;z-index:100;margin-top:4px}
.header-nav .dropdown-menu a{display:block;padding:10px 16px;color:#111b21;border-radius:0;font-size:14px;white-space:nowrap}
.header-nav .dropdown-menu a:hover{background:#f0f2f5}
.header-nav .nav-item-wrap{position:relative}
.header-nav .nav-item-wrap:hover .dropdown-menu{display:block}
.header-right{display:flex;align-items:center;gap:12px}
.header-right .lang-btn{padding:6px 14px;font-size:13px;color:#667781;border:1px solid #e9edef;border-radius:24px;background:#fff;cursor:pointer;transition:all .2s;display:flex;align-items:center;gap:4px}
.header-right .lang-btn:hover{background:#f0f2f5;color:#111b21}
.header-right .download-top-btn{display:inline-flex;align-items:center;padding:8px 22px;font-size:14px;font-weight:600;color:#fff;background:#25d366;border-radius:24px;transition:background .2s}
.header-right .download-top-btn:hover{background:#20bd5b}

/* Hero Section */
.hero{text-align:center;padding:120px 20px 60px}
.hero h1{font-size:52px;font-weight:700;color:#111b21;margin-bottom:24px;letter-spacing:-1px}
.hero p{font-size:18px;color:#667781;margin-bottom:40px;max-width:600px;margin-left:auto;margin-right:auto}
.hero-buttons{display:flex;gap:16px;justify-content:center;flex-wrap:wrap;margin-bottom:40px}
.hero-buttons .btn-primary{display:inline-flex;align-items:center;gap:10px;padding:14px 32px;font-size:16px;font-weight:600;color:#fff;background:#25d366;border-radius:30px;transition:background .2s}
.hero-buttons .btn-primary:hover{background:#20bd5b}
.hero-buttons .btn-secondary{display:inline-flex;align-items:center;gap:10px;padding:14px 32px;font-size:16px;font-weight:600;color:#111b21;background:#f0f2f5;border-radius:30px;transition:background .2s}
.hero-buttons .btn-secondary:hover{background:#e0e3e7}
.hero-image{max-width:900px;margin:0 auto;padding:0 20px}
.hero-platforms{display:flex;justify-content:center;gap:24px;margin-top:40px;flex-wrap:wrap}
.hero-platform{display:flex;flex-direction:column;align-items:center;gap:8px;color:#667781;font-size:13px;min-width:64px}

/* Section */
.section{padding:80px 20px}
.section-alt{background:#f9fafa}
.section-title{font-size:36px;font-weight:700;color:#111b21;margin-bottom:16px;text-align:center}
.section-subtitle{font-size:17px;color:#667781;text-align:center;max-width:600px;margin:0 auto 48px}
.features-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:24px;max-width:960px;margin:0 auto}
.feature-card{text-align:center;padding:32px 20px;border:1px solid #e9edef;border-radius:16px;transition:box-shadow .3s}
.feature-card:hover{box-shadow:0 4px 20px rgba(0,0,0,.06)}
.feature-card .icon{width:48px;height:48px;margin:0 auto 16px;background:#d9fdd3;border-radius:50%;display:flex;align-items:center;justify-content:center}
.feature-card h3{font-size:18px;font-weight:600;color:#111b21;margin-bottom:8px}
.feature-card p{font-size:14px;color:#667781;line-height:1.6}

/* Hero image row */
.hero-visual{text-align:center;padding:0 20px 60px}
.hero-visual img{max-width:800px;border-radius:12px}

/* CTA */
.cta-section{text-align:center;padding:80px 20px;background:#f9fafa}
.cta-section h2{font-size:36px;font-weight:700;color:#111b21;margin-bottom:16px}
.cta-section p{font-size:17px;color:#667781;margin-bottom:32px}
.cta-section .btn-primary{display:inline-flex;align-items:center;gap:10px;padding:14px 32px;font-size:16px;font-weight:600;color:#fff;background:#25d366;border-radius:30px;transition:background .2s}
.cta-section .btn-primary:hover{background:#20bd5b}

/* Footer */
.footer{background:#111b21;color:#fff;padding:60px 0 0}
.footer-container{max-width:1100px;margin:0 auto;padding:0 20px}
.footer-grid{display:grid;grid-template-columns:2fr 1fr 1fr 1fr 1fr;gap:40px;padding-bottom:40px;border-bottom:1px solid rgba(255,255,255,.1)}
.footer-brand p{font-size:13px;color:#8696a0;line-height:1.6;margin-top:12px}
.footer-col h5{font-size:14px;font-weight:600;color:#fff;margin-bottom:16px}
.footer-col a{display:block;font-size:13px;color:#8696a0;padding:4px 0;transition:color .2s}
.footer-col a:hover{color:#25d366}
.footer-bottom{display:flex;justify-content:space-between;align-items:center;padding:24px 0;flex-wrap:wrap;gap:12px}
.footer-bottom .footer-links{display:flex;gap:20px;flex-wrap:wrap}
.footer-bottom .footer-links a{font-size:12px;color:#8696a0;transition:color .2s}
.footer-bottom .footer-links a:hover{color:#25d366}
.footer-bottom .copyright{font-size:12px;color:#8696a0}

/* Page Hero */
.page-hero{text-align:center;padding:120px 20px 60px}
.page-hero h1{font-size:44px;font-weight:700;color:#111b21;margin-bottom:16px}
.page-hero p{font-size:17px;color:#667781;max-width:600px;margin:0 auto;line-height:1.6}

/* Download Page */
.download-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:24px;max-width:700px;margin:0 auto 60px}
.download-card{border:1px solid #e9edef;border-radius:16px;padding:32px 24px;text-align:center;transition:box-shadow .3s}
.download-card:hover{box-shadow:0 4px 20px rgba(0,0,0,.06)}
.download-card .dl-icon{width:48px;height:48px;margin:0 auto 16px;background:#d9fdd3;border-radius:50%;display:flex;align-items:center;justify-content:center}
.download-card h3{font-size:20px;font-weight:600;color:#111b21;margin-bottom:6px}
.download-card .dl-sub{font-size:13px;color:#8696a0;margin-bottom:20px}
.download-card .dl-btn{display:inline-flex;align-items:center;gap:8px;padding:12px 28px;font-size:14px;font-weight:600;color:#fff;background:#25d366;border-radius:30px;transition:background .2s}
.download-card .dl-btn:hover{background:#20bd5b}
.download-card .dl-btn-outline{display:inline-flex;align-items:center;gap:8px;padding:12px 28px;font-size:14px;font-weight:600;color:#111b21;background:#f0f2f5;border-radius:30px;transition:background .2s;margin-top:8px}
.download-card .dl-btn-outline:hover{background:#e0e3e7}
.download-note{text-align:center;max-width:500px;margin:0 auto 40px;font-size:13px;color:#8696a0;line-height:1.6}
.download-note a{color:#25d366;text-decoration:underline}
.download-faq{max-width:600px;margin:0 auto}
.download-faq h3{font-size:18px;font-weight:600;color:#111b21;margin-bottom:4px;cursor:pointer}
.download-faq .faq-item{padding:20px 0;border-bottom:1px solid #e9edef}
.download-faq .faq-item h3{font-size:16px;margin-bottom:8px}
.download-faq .faq-item p{font-size:14px;color:#667781;line-height:1.6}

/* About Page */
.about-content{max-width:700px;margin:0 auto;text-align:center;padding:0 20px}
.about-content h2{font-size:28px;font-weight:700;color:#111b21;margin-bottom:20px}
.about-content p{font-size:16px;color:#667781;line-height:1.8;margin-bottom:20px}
.about-stats{display:grid;grid-template-columns:repeat(3,1fr);gap:24px;max-width:700px;margin:40px auto 0}
.about-stat{text-align:center;padding:24px}
.about-stat .num{font-size:36px;font-weight:700;color:#25d366;margin-bottom:4px}
.about-stat .label{font-size:14px;color:#667781}
.team-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:24px;max-width:700px;margin:0 auto}
.team-card{text-align:center}
.team-card .avatar{width:80px;height:80px;border-radius:50%;background:#d9fdd3;margin:0 auto 12px;display:flex;align-items:center;justify-content:center;font-size:28px;color:#25d366;font-weight:600}
.team-card h4{font-size:15px;font-weight:600;color:#111b21;margin-bottom:4px}
.team-card p{font-size:13px;color:#8696a0}

/* Privacy Page */
.privacy-content{max-width:700px;margin:0 auto;padding:0 20px}
.privacy-content h2{font-size:24px;font-weight:700;color:#111b21;margin:32px 0 12px}
.privacy-content h3{font-size:18px;font-weight:600;color:#111b21;margin:24px 0 10px}
.privacy-content p{font-size:15px;color:#667781;line-height:1.7;margin-bottom:14px}
.privacy-content ul{padding-left:24px;margin-bottom:14px}
.privacy-content ul li{font-size:15px;color:#667781;line-height:1.7;list-style:disc;margin-bottom:6px}

/* Features Page - nested grid */
.features-detail-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:24px;max-width:960px;margin:0 auto}
.features-detail-card{padding:32px 20px;border:1px solid #e9edef;border-radius:16px}
.features-detail-card .fd-icon{width:48px;height:48px;margin-bottom:16px;background:#d9fdd3;border-radius:12px;display:flex;align-items:center;justify-content:center}
.features-detail-card h3{font-size:18px;font-weight:600;color:#111b21;margin-bottom:8px}
.features-detail-card p{font-size:14px;color:#667781;line-height:1.6}
.features-showcase{display:grid;grid-template-columns:1fr 1fr;gap:60px;max-width:900px;margin:0 auto;align-items:center}
.features-showcase-text h3{font-size:24px;font-weight:700;color:#111b21;margin-bottom:12px}
.features-showcase-text p{font-size:15px;color:#667781;line-height:1.7}

/* Business Page */
.business-plans{display:grid;grid-template-columns:repeat(2,1fr);gap:24px;max-width:700px;margin:0 auto}
.business-card{border:1px solid #e9edef;border-radius:16px;padding:32px 24px;text-align:center;transition:box-shadow .3s}
.business-card:hover{box-shadow:0 4px 20px rgba(0,0,0,.06)}
.business-card h3{font-size:22px;font-weight:700;color:#111b21;margin-bottom:10px}
.business-card p{font-size:14px;color:#667781;line-height:1.6;margin-bottom:20px}
.business-card .biz-btn{padding:12px 28px;font-size:14px;font-weight:600;color:#fff;background:#25d366;border-radius:30px;display:inline-block;transition:background .2s}
.business-card .biz-btn:hover{background:#20bd5b}

/* Language Page */
.lang-banner{text-align:center;padding:120px 20px 60px;background:linear-gradient(180deg,#d9fdd3 0%,#fff 100%)}
.lang-banner h1{font-size:40px;font-weight:700;color:#111b21;margin-bottom:16px}
.lang-banner p{font-size:17px;color:#667781;max-width:500px;margin:0 auto 32px}
.lang-btn{padding:12px 28px;font-size:14px;font-weight:600;color:#fff;background:#25d366;border-radius:30px;display:inline-block;transition:background .2s}
.lang-btn:hover{background:#20bd5b}
.lang-features{display:grid;grid-template-columns:repeat(3,1fr);gap:24px;max-width:800px;margin:0 auto}
.lang-feature-card{text-align:center;padding:24px;border:1px solid #e9edef;border-radius:16px}
.lang-feature-card h3{font-size:16px;font-weight:600;color:#111b21;margin-bottom:8px}
.lang-feature-card p{font-size:13px;color:#667781;line-height:1.6}

/* Security Page */
.security-content{max-width:700px;margin:0 auto;padding:0 20px}
.security-content h2{font-size:24px;font-weight:700;color:#111b21;margin:32px 0 12px}
.security-content h3{font-size:18px;font-weight:600;color:#111b21;margin:24px 0 10px}
.security-content p{font-size:15px;color:#667781;line-height:1.7;margin-bottom:14px}
.security-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:20px;max-width:700px;margin:30px auto}
.security-item{text-align:center;padding:20px;border:1px solid #e9edef;border-radius:12px}
.security-item h4{font-size:14px;font-weight:600;color:#111b21;margin-bottom:6px}
.security-item p{font-size:12px;color:#8696a0}

/* Blog page */
.blog-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:24px;max-width:900px;margin:0 auto}
.blog-card{border:1px solid #e9edef;border-radius:16px;overflow:hidden;transition:box-shadow .3s}
.blog-card:hover{box-shadow:0 4px 20px rgba(0,0,0,.06)}
.blog-card .blog-img{height:180px;background:#d9fdd3;display:flex;align-items:center;justify-content:center;font-size:40px;color:#25d366}
.blog-card .blog-body{padding:20px}
.blog-card .blog-body .blog-date{font-size:12px;color:#8696a0;margin-bottom:6px}
.blog-card .blog-body h3{font-size:16px;font-weight:600;color:#111b21;margin-bottom:8px}
.blog-card .blog-body p{font-size:13px;color:#667781;line-height:1.5}

@media(max-width:768px){
.hero h1{font-size:32px}
.section-title{font-size:28px}
.features-grid,.features-detail-grid,.lang-features,.blog-grid,.business-plans,.about-stats{grid-template-columns:1fr}
.features-showcase{grid-template-columns:1fr;gap:30px}
.footer-grid{grid-template-columns:1fr 1fr;gap:24px}
.header-nav{display:none}
.hero-image img{max-width:100%}
.download-grid{grid-template-columns:1fr}
.team-grid{grid-template-columns:repeat(2,1fr)}
.security-grid{grid-template-columns:1fr}
}
@media(max-width:480px){
.footer-grid{grid-template-columns:1fr}
.team-grid{grid-template-columns:1fr}
}