*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
:root{
  --primary:#e74c3c;
  --primary-dark:#c0392b;
  --text:#333;
  --text-light:#666;
  --bg:#fff;
  --bg-light:#f8f9fa;
  --border:#e0e0e0;
  --shadow:0 2px 12px rgba(0,0,0,.08);
  --radius:8px;
  --max-width:1200px;
}
html{scroll-behavior:smooth}
body{font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Hiragino Sans GB","Microsoft YaHei",sans-serif;color:var(--text);line-height:1.7;background:var(--bg)}
a{color:var(--primary);text-decoration:none;transition:color .2s}
a:hover{color:var(--primary-dark)}
img{max-width:100%;height:auto;display:block}
.container{max-width:var(--max-width);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;height:64px}
.logo{display:flex;align-items:center;gap:10px;font-size:1.35rem;font-weight:700;color:var(--text)}
.logo img{width:36px;height:36px}
.nav{display:flex;gap:28px;list-style:none}
.nav a{color:var(--text);font-size:.95rem;font-weight:500}
.nav a:hover,.nav a.active{color:var(--primary)}
.nav-toggle{display:none;background:none;border:none;font-size:1.5rem;cursor:pointer;color:var(--text)}

/* Hero */
.hero{background:linear-gradient(135deg,#fff5f5 0%,#fff 50%,#f0f7ff 100%);padding:80px 0 60px;text-align:center}
.hero h1{font-size:2.6rem;font-weight:800;margin-bottom:16px;line-height:1.3}
.hero p{font-size:1.15rem;color:var(--text-light);max-width:680px;margin:0 auto 32px}
.btn{display:inline-block;padding:14px 36px;border-radius:50px;font-size:1rem;font-weight:600;transition:all .25s;cursor:pointer;border:none}
.btn-primary{background:var(--primary);color:#fff;box-shadow:0 4px 14px rgba(231,76,60,.35)}
.btn-primary:hover{background:var(--primary-dark);color:#fff;transform:translateY(-2px);box-shadow:0 6px 20px rgba(231,76,60,.4)}
.btn-outline{background:transparent;color:var(--primary);border:2px solid var(--primary)}
.btn-outline:hover{background:var(--primary);color:#fff}

/* Sections */
section{padding:70px 0}
.section-title{text-align:center;margin-bottom:48px}
.section-title h2{font-size:2rem;font-weight:700;margin-bottom:10px}
.section-title p{color:var(--text-light);font-size:1.05rem}
.bg-light{background:var(--bg-light)}

/* Feature Grid */
.features-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:30px}
.feature-card{background:#fff;border-radius:var(--radius);padding:36px 28px;box-shadow:var(--shadow);text-align:center;transition:transform .25s}
.feature-card:hover{transform:translateY(-4px)}
.feature-icon{width:64px;height:64px;margin:0 auto 20px;background:linear-gradient(135deg,var(--primary),#ff6b6b);border-radius:50%;display:flex;align-items:center;justify-content:center;font-size:1.6rem;color:#fff}
.feature-card h3{font-size:1.2rem;margin-bottom:12px}
.feature-card p{color:var(--text-light);font-size:.95rem}

/* Stats */
.stats-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:24px;text-align:center}
.stat-item{padding:30px 16px}
.stat-item .number{font-size:2.4rem;font-weight:800;color:var(--primary)}
.stat-item .label{margin-top:6px;color:var(--text-light);font-size:.95rem}

/* Testimonials */
.testimonials-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:28px}
.testimonial-card{background:#fff;border-radius:var(--radius);padding:32px 28px;box-shadow:var(--shadow);position:relative}
.testimonial-card::before{content:"\201C";font-size:3rem;color:var(--primary);opacity:.3;position:absolute;top:10px;left:20px;line-height:1}
.testimonial-card p{color:var(--text-light);font-size:.95rem;margin-bottom:16px;padding-top:20px;font-style:italic}
.testimonial-card .author{font-weight:600;font-size:.9rem}

/* FAQ */
.faq-list{max-width:800px;margin:0 auto}
.faq-item{border-bottom:1px solid var(--border);padding:20px 0}
.faq-question{width:100%;background:none;border:none;text-align:left;font-size:1.05rem;font-weight:600;cursor:pointer;display:flex;justify-content:space-between;align-items:center;color:var(--text);padding:0;font-family:inherit}
.faq-question::after{content:"+";font-size:1.4rem;color:var(--primary);transition:transform .3s}
.faq-item.open .faq-question::after{transform:rotate(45deg)}
.faq-answer{max-height:0;overflow:hidden;transition:max-height .35s ease;color:var(--text-light);font-size:.95rem}
.faq-item.open .faq-answer{max-height:600px;padding-top:14px}

/* Security */
.security-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:28px}
.security-card{background:#fff;border-radius:var(--radius);padding:32px 24px;box-shadow:var(--shadow);text-align:center}
.security-card h3{margin:16px 0 10px;font-size:1.1rem}
.security-card p{color:var(--text-light);font-size:.92rem}

/* Download Page */
.download-hero{padding:60px 0;text-align:center;background:linear-gradient(135deg,#fff5f5,#f0f7ff)}
.download-cards{display:grid;grid-template-columns:repeat(auto-fit,minmax(260px,1fr));gap:28px;margin-top:40px}
.download-card{background:#fff;border-radius:var(--radius);padding:36px 28px;box-shadow:var(--shadow);text-align:center;transition:transform .25s}
.download-card:hover{transform:translateY(-4px)}
.download-card .platform-icon{font-size:3rem;margin-bottom:16px}
.download-card h3{margin-bottom:8px}
.download-card p{color:var(--text-light);font-size:.9rem;margin-bottom:20px}
.download-card .version{color:var(--text-light);font-size:.85rem;margin-bottom:16px}
.system-req{max-width:800px;margin:50px auto 0;background:#fff;border-radius:var(--radius);padding:36px;box-shadow:var(--shadow)}
.system-req h3{margin-bottom:20px;text-align:center}
.system-req table{width:100%;border-collapse:collapse}
.system-req th,.system-req td{padding:12px 16px;text-align:left;border-bottom:1px solid var(--border);font-size:.92rem}
.system-req th{background:var(--bg-light);font-weight:600}

/* Article */
.article-header{padding:50px 0 30px;background:var(--bg-light)}
.article-header h1{font-size:2rem;margin-bottom:12px;line-height:1.4}
.article-meta{color:var(--text-light);font-size:.9rem}
.article-body{max-width:800px;margin:0 auto;padding:40px 20px}
.article-body h2{font-size:1.4rem;margin:32px 0 14px;color:var(--text)}
.article-body h3{font-size:1.15rem;margin:24px 0 10px}
.article-body p{margin-bottom:16px;color:var(--text-light);font-size:.97rem}
.article-body ul,.article-body ol{margin:0 0 16px 24px;color:var(--text-light);font-size:.97rem}
.article-body li{margin-bottom:8px}
.article-nav{display:flex;justify-content:space-between;margin-top:40px;padding-top:24px;border-top:1px solid var(--border)}

/* Article List */
.articles-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(320px,1fr));gap:28px}
.article-card{background:#fff;border-radius:var(--radius);overflow:hidden;box-shadow:var(--shadow);transition:transform .25s}
.article-card:hover{transform:translateY(-3px)}
.article-card-body{padding:24px}
.article-card-body h3{margin-bottom:10px;font-size:1.1rem}
.article-card-body p{color:var(--text-light);font-size:.92rem;margin-bottom:14px}
.article-card-body .date{color:var(--text-light);font-size:.82rem}

/* Footer */
.site-footer{background:#2c3e50;color:#bdc3c7;padding:50px 0 24px}
.footer-grid{display:grid;grid-template-columns:2fr 1fr 1fr;gap:40px;margin-bottom:36px}
.footer-grid h4{color:#fff;margin-bottom:16px;font-size:1rem}
.footer-grid p,.footer-grid li{font-size:.9rem;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:.85rem}

/* Breadcrumb */
.breadcrumb{padding:16px 0;font-size:.88rem;color:var(--text-light)}
.breadcrumb a{color:var(--text-light)}
.breadcrumb a:hover{color:var(--primary)}

/* Auto articles section */
.auto-articles{margin-top:20px}
.auto-articles .loading{text-align:center;color:var(--text-light);padding:30px}

@media(max-width:900px){
  .features-grid,.testimonials-grid,.security-grid,.stats-grid{grid-template-columns:1fr}
  .stats-grid{grid-template-columns:repeat(2,1fr)}
  .footer-grid{grid-template-columns:1fr}
  .hero h1{font-size:2rem}
}
@media(max-width:768px){
  .nav{display:none;position:absolute;top:64px;left:0;right:0;background:#fff;flex-direction:column;padding:16px 20px;box-shadow:var(--shadow);gap:0}
  .nav.open{display:flex}
  .nav li{padding:10px 0;border-bottom:1px solid var(--border)}
  .nav-toggle{display:block}
  .header-inner{position:relative}
}