*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
:root{
  --primary:#e74c3c;
  --primary-dark:#c0392b;
  --secondary:#2c3e50;
  --accent:#3498db;
  --light:#f8f9fa;
  --gray:#6c757d;
  --border:#dee2e6;
  --shadow:0 2px 12px rgba(0,0,0,.08);
  --radius:8px;
}
html{scroll-behavior:smooth}
body{font-family:"Microsoft YaHei","PingFang SC","Helvetica Neue",Arial,sans-serif;color:#333;line-height:1.7;background:#fff}
a{color:var(--accent);text-decoration:none;transition:color .2s}
a:hover{color:var(--primary)}
img{max-width:100%;height:auto}
.container{max-width:1140px;margin:0 auto;padding:0 20px}

/* Header */
.site-header{background:#fff;box-shadow:var(--shadow);position:sticky;top:0;z-index:100}
.header-inner{display:flex;align-items:center;justify-content:space-between;padding:14px 0}
.logo{display:flex;align-items:center;gap:10px;font-size:1.35rem;font-weight:700;color:var(--secondary)}
.logo img{width:36px;height:36px}
.nav-links{display:flex;gap:28px;list-style:none}
.nav-links a{color:var(--secondary);font-weight:500;font-size:.95rem}
.nav-links a:hover,.nav-links a.active{color:var(--primary)}
.btn-download{display:inline-block;background:var(--primary);color:#fff!important;padding:10px 24px;border-radius:var(--radius);font-weight:600;font-size:.9rem;transition:background .2s}
.btn-download:hover{background:var(--primary-dark)}
.menu-toggle{display:none;background:none;border:none;font-size:1.5rem;cursor:pointer;color:var(--secondary)}

/* Hero */
.hero{background:linear-gradient(135deg,#2c3e50 0%,#3498db 100%);color:#fff;padding:80px 0 70px;text-align:center}
.hero h1{font-size:2.4rem;margin-bottom:16px;font-weight:700}
.hero p{font-size:1.15rem;opacity:.92;max-width:680px;margin:0 auto 30px}
.hero .btn-download{font-size:1rem;padding:14px 36px}

/* Sections */
section{padding:60px 0}
.section-title{text-align:center;margin-bottom:48px}
.section-title h2{font-size:1.8rem;color:var(--secondary);margin-bottom:10px}
.section-title p{color:var(--gray);font-size:1.05rem}

/* Features Grid */
.features-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:28px}
.feature-card{background:#fff;border:1px solid var(--border);border-radius:var(--radius);padding:32px 24px;text-align:center;transition:transform .2s,box-shadow .2s}
.feature-card:hover{transform:translateY(-4px);box-shadow:var(--shadow)}
.feature-icon{width:56px;height:56px;background:linear-gradient(135deg,var(--primary),#e67e22);border-radius:50%;display:flex;align-items:center;justify-content:center;margin:0 auto 18px;font-size:1.5rem;color:#fff}
.feature-card h3{font-size:1.15rem;margin-bottom:10px;color:var(--secondary)}
.feature-card p{color:var(--gray);font-size:.92rem}

/* Stats */
.stats{background:var(--light)}
.stats-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:24px;text-align:center}
.stat-item h3{font-size:2rem;color:var(--primary);font-weight:700}
.stat-item p{color:var(--gray);margin-top:4px;font-size:.9rem}

/* Testimonials */
.testimonials-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:24px}
.testimonial-card{background:var(--light);border-radius:var(--radius);padding:28px 24px;position:relative}
.testimonial-card::before{content:"\201C";font-size:3rem;color:var(--primary);opacity:.3;position:absolute;top:8px;left:16px;line-height:1}
.testimonial-card p{font-style:italic;color:#555;margin-bottom:14px;padding-top:20px;font-size:.93rem}
.testimonial-card .author{font-weight:600;color:var(--secondary);font-size:.88rem}

/* Security */
.security-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:28px}
.security-card{border-left:4px solid var(--primary);padding:20px 24px;background:var(--light);border-radius:0 var(--radius) var(--radius) 0}
.security-card h3{font-size:1.05rem;margin-bottom:8px;color:var(--secondary)}
.security-card p{color:var(--gray);font-size:.9rem}

/* FAQ */
.faq-list{max-width:800px;margin:0 auto}
.faq-item{border:1px solid var(--border);border-radius:var(--radius);margin-bottom:12px;overflow:hidden}
.faq-question{width:100%;background:#fff;border:none;padding:18px 24px;text-align:left;font-size:1rem;font-weight:600;color:var(--secondary);cursor:pointer;display:flex;justify-content:space-between;align-items:center;font-family:inherit}
.faq-question:hover{background:var(--light)}
.faq-question .icon{font-size:1.2rem;color:var(--primary);transition:transform .3s}
.faq-item.active .faq-question .icon{transform:rotate(45deg)}
.faq-answer{max-height:0;overflow:hidden;transition:max-height .35s ease}
.faq-answer-inner{padding:0 24px 18px;color:var(--gray);font-size:.92rem;line-height:1.8}
.faq-item.active .faq-answer{max-height:600px}

/* Articles */
.articles-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:24px}
.article-card{border:1px solid var(--border);border-radius:var(--radius);overflow:hidden;transition:box-shadow .2s}
.article-card:hover{box-shadow:var(--shadow)}
.article-card .card-body{padding:20px}
.article-card h3{font-size:1.05rem;margin-bottom:8px;color:var(--secondary)}
.article-card h3 a{color:inherit}
.article-card h3 a:hover{color:var(--primary)}
.article-card .meta{font-size:.82rem;color:var(--gray);margin-bottom:10px}
.article-card p{color:var(--gray);font-size:.88rem}
.article-card .read-more{display:inline-block;margin-top:12px;color:var(--primary);font-weight:600;font-size:.88rem}

/* Article Page */
.article-header{padding:50px 0 30px;background:var(--light)}
.article-header h1{font-size:2rem;color:var(--secondary);margin-bottom:12px}
.article-meta{color:var(--gray);font-size:.88rem}
.article-content{max-width:800px;margin:0 auto;padding:40px 20px}
.article-content h2{font-size:1.4rem;margin:32px 0 14px;color:var(--secondary)}
.article-content h3{font-size:1.15rem;margin:24px 0 10px;color:var(--secondary)}
.article-content p{margin-bottom:16px;color:#444;font-size:.95rem}
.article-content ul,.article-content ol{margin:0 0 16px 24px;color:#444}
.article-content li{margin-bottom:6px}
.article-content blockquote{border-left:4px solid var(--primary);padding:12px 20px;background:var(--light);margin:20px 0;font-style:italic;color:#555}

/* Download Page */
.download-hero{text-align:center;padding:50px 0;background:var(--light)}
.download-hero h1{font-size:2rem;color:var(--secondary);margin-bottom:12px}
.download-hero p{color:var(--gray);max-width:600px;margin:0 auto 30px}
.download-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:24px;max-width:900px;margin:0 auto}
.download-card{text-align:center;border:1px solid var(--border);border-radius:var(--radius);padding:36px 24px;background:#fff}
.download-card .platform-icon{font-size:2.5rem;margin-bottom:14px}
.download-card h3{margin-bottom:8px;color:var(--secondary)}
.download-card p{color:var(--gray);font-size:.88rem;margin-bottom:18px}
.download-steps{max-width:700px;margin:40px auto 0}
.download-steps h2{text-align:center;margin-bottom:24px;color:var(--secondary)}
.download-steps ol{padding-left:24px}
.download-steps li{margin-bottom:10px;color:#444}

/* Daily Update Badge */
.update-badge{display:inline-block;background:#e8f5e9;color:#2e7d32;font-size:.78rem;padding:3px 10px;border-radius:12px;margin-left:8px}

/* Footer */
.site-footer{background:var(--secondary);color:#bdc3c7;padding:48px 0 24px}
.footer-grid{display:grid;grid-template-columns:2fr 1fr 1fr;gap:32px;margin-bottom:32px}
.footer-grid h4{color:#fff;margin-bottom:14px;font-size:1rem}
.footer-grid p,.footer-grid li{font-size:.88rem;line-height:2}
.footer-grid ul{list-style:none}
.footer-grid a{color:#bdc3c7}
.footer-grid a:hover{color:#fff}
.footer-bottom{text-align:center;padding-top:24px;border-top:1px solid rgba(255,255,255,.1);font-size:.82rem}

/* Breadcrumb */
.breadcrumb{padding:14px 0;font-size:.85rem;color:var(--gray)}
.breadcrumb a{color:var(--gray)}
.breadcrumb span{margin:0 6px}

/* Responsive */
@media(max-width:900px){
  .features-grid,.testimonials-grid,.security-grid,.articles-grid,.download-grid,.stats-grid{grid-template-columns:1fr 1fr}
  .footer-grid{grid-template-columns:1fr 1fr}
  .hero h1{font-size:1.8rem}
}
@media(max-width:600px){
  .nav-links{display:none;position:absolute;top:100%;left:0;right:0;background:#fff;flex-direction:column;padding:16px 20px;box-shadow:var(--shadow);gap:12px}
  .nav-links.open{display:flex}
  .menu-toggle{display:block}
  .features-grid,.testimonials-grid,.security-grid,.articles-grid,.download-grid,.stats-grid,.footer-grid{grid-template-columns:1fr}
  .hero{padding:50px 0 40px}
  .hero h1{font-size:1.5rem}
  section{padding:40px 0}
}