*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
:root{
  --primary:#e74c3c;
  --primary-dark:#c0392b;
  --secondary:#2c3e50;
  --accent:#3498db;
  --bg:#f8f9fa;
  --text:#333;
  --text-light:#666;
  --white:#fff;
  --shadow:0 2px 12px rgba(0,0,0,.08);
  --radius:8px;
  --max-w: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(--accent);text-decoration:none;transition:color .2s}
a:hover{color:var(--primary)}
img{max-width:100%;height:auto}
.container{max-width:var(--max-w);margin:0 auto;padding:0 20px}

/* Header */
.site-header{background:var(--white);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(--secondary)}
.logo img{width:36px;height:36px}
.nav{display:flex;gap:28px;list-style:none}
.nav a{color:var(--secondary);font-weight:500;font-size:.95rem}
.nav a:hover,.nav a.active{color:var(--primary)}
.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:var(--white);padding:80px 0;text-align:center}
.hero h1{font-size:2.6rem;margin-bottom:16px;font-weight:700}
.hero p{font-size:1.15rem;max-width:680px;margin:0 auto 32px;opacity:.92;line-height:1.8}
.btn{display:inline-block;padding:14px 36px;border-radius:50px;font-weight:600;font-size:1rem;transition:all .25s;cursor:pointer;border:none}
.btn-primary{background:var(--primary);color:var(--white)}
.btn-primary:hover{background:var(--primary-dark);color:var(--white);transform:translateY(-2px);box-shadow:0 4px 16px rgba(231,76,60,.4)}
.btn-outline{background:transparent;color:var(--white);border:2px solid var(--white);margin-left:12px}
.btn-outline:hover{background:var(--white);color:var(--secondary)}

/* Sections */
.section{padding:72px 0}
.section-title{text-align:center;margin-bottom:48px}
.section-title h2{font-size:2rem;color:var(--secondary);margin-bottom:10px}
.section-title p{color:var(--text-light);font-size:1.05rem}

/* Features Grid */
.features-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:28px}
.feature-card{background:var(--white);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{font-size:2.8rem;margin-bottom:16px}
.feature-card h3{font-size:1.2rem;color:var(--secondary);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{background:var(--white);border-radius:var(--radius);padding:32px 20px;box-shadow:var(--shadow)}
.stat-item h3{font-size:2.2rem;color:var(--primary);margin-bottom:6px}
.stat-item p{color:var(--text-light);font-size:.95rem}

/* Testimonials */
.testimonials-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:28px}
.testimonial-card{background:var(--white);border-radius:var(--radius);padding:32px;box-shadow:var(--shadow);position:relative}
.testimonial-card::before{content:'\201C';font-size:3rem;color:var(--primary);opacity:.3;position:absolute;top:8px;left:20px;line-height:1}
.testimonial-card p{color:var(--text-light);font-style:italic;margin-bottom:16px;padding-top:20px}
.testimonial-card cite{color:var(--secondary);font-style:normal;font-weight:600;font-size:.9rem}

/* FAQ */
.faq-list{max-width:800px;margin:0 auto}
.faq-item{background:var(--white);border-radius:var(--radius);margin-bottom:12px;box-shadow:var(--shadow);overflow:hidden}
.faq-question{width:100%;background:none;border:none;padding:20px 24px;text-align:left;font-size:1rem;font-weight:600;color:var(--secondary);cursor:pointer;display:flex;justify-content:space-between;align-items:center}
.faq-question::after{content:'+';font-size:1.3rem;color:var(--primary);transition:transform .2s}
.faq-item.active .faq-question::after{transform:rotate(45deg)}
.faq-answer{max-height:0;overflow:hidden;transition:max-height .3s ease}
.faq-answer-inner{padding:0 24px 20px;color:var(--text-light);font-size:.95rem;line-height:1.8}
.faq-item.active .faq-answer{max-height:600px}

/* Download Page */
.download-hero{padding:60px 0;text-align:center;background:var(--white)}
.platform-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:20px;margin:40px 0}
.platform-card{background:var(--bg);border-radius:var(--radius);padding:28px;text-align:center;transition:all .25s;border:2px solid transparent}
.platform-card:hover{border-color:var(--primary);background:var(--white);box-shadow:var(--shadow)}
.platform-card .icon{font-size:2.5rem;margin-bottom:10px}
.platform-card h3{color:var(--secondary);margin-bottom:4px}
.platform-card p{color:var(--text-light);font-size:.85rem}
.version-cards{display:grid;grid-template-columns:repeat(3,1fr);gap:28px;margin-top:40px}
.version-card{background:var(--white);border-radius:var(--radius);padding:32px;box-shadow:var(--shadow)}
.version-card h3{font-size:1.3rem;color:var(--secondary);margin-bottom:16px}
.version-card ul{list-style:none;margin:16px 0}
.version-card li{padding:6px 0;color:var(--text-light);font-size:.92rem}
.version-card li::before{content:'✓';color:var(--primary);margin-right:8px;font-weight:700}
.version-info{background:var(--bg);border-radius:var(--radius);padding:16px;margin-top:16px;font-size:.88rem;color:var(--text-light)}
.version-info strong{color:var(--secondary)}
.sys-req-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:28px;margin-top:32px}
.sys-req-card{background:var(--white);border-radius:var(--radius);padding:28px;box-shadow:var(--shadow)}
.sys-req-card h3{color:var(--secondary);margin-bottom:16px;font-size:1.1rem}
.sys-req-card ul{list-style:none}
.sys-req-card li{padding:5px 0;color:var(--text-light);font-size:.9rem}

/* Article */
.article-hero{background:linear-gradient(135deg,#2c3e50,#34495e);color:var(--white);padding:60px 0;text-align:center}
.article-hero h1{font-size:2rem;margin-bottom:12px}
.article-meta{opacity:.8;font-size:.9rem}
.article-body{max-width:800px;margin:0 auto;padding:48px 20px}
.article-body h2{font-size:1.5rem;color:var(--secondary);margin:32px 0 16px;padding-bottom:8px;border-bottom:2px solid var(--primary)}
.article-body h3{font-size:1.2rem;color:var(--secondary);margin:24px 0 12px}
.article-body p{margin-bottom:16px;color:var(--text-light);line-height:1.9}
.article-body ul,.article-body ol{margin:12px 0 16px 24px;color:var(--text-light)}
.article-body li{margin-bottom:8px;line-height:1.8}
.article-list-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:28px;margin-top:32px}
.article-card{background:var(--white);border-radius:var(--radius);overflow:hidden;box-shadow:var(--shadow);transition:transform .25s}
.article-card:hover{transform:translateY(-4px)}
.article-card-body{padding:24px}
.article-card h3{font-size:1.1rem;color:var(--secondary);margin-bottom:10px}
.article-card p{color:var(--text-light);font-size:.9rem;margin-bottom:12px}
.article-card .date{color:var(--text-light);font-size:.82rem}
.article-card .read-more{color:var(--primary);font-weight:600;font-size:.9rem}

/* Footer */
.site-footer{background:var(--secondary);color:rgba(255,255,255,.8);padding:48px 0 24px}
.footer-grid{display:grid;grid-template-columns:2fr 1fr 1fr;gap:40px;margin-bottom:32px}
.footer-grid h4{color:var(--white);margin-bottom:16px;font-size:1.05rem}
.footer-grid p,.footer-grid li{font-size:.9rem;line-height:2}
.footer-grid ul{list-style:none}
.footer-grid a{color:rgba(255,255,255,.7)}
.footer-grid a:hover{color:var(--white)}
.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)}

/* Security section */
.security-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:28px}
.security-card{background:var(--white);border-radius:var(--radius);padding:32px;box-shadow:var(--shadow);text-align:center}
.security-card .icon{font-size:2.2rem;margin-bottom:14px}
.security-card h3{color:var(--secondary);margin-bottom:10px}
.security-card p{color:var(--text-light);font-size:.93rem}

/* Responsive */
@media(max-width:992px){
  .features-grid,.testimonials-grid,.version-cards,.sys-req-grid,.security-grid{grid-template-columns:repeat(2,1fr)}
  .stats-grid{grid-template-columns:repeat(2,1fr)}
  .platform-grid{grid-template-columns:repeat(2,1fr)}
  .article-list-grid{grid-template-columns:repeat(2,1fr)}
  .footer-grid{grid-template-columns:1fr 1fr}
}
@media(max-width:768px){
  .nav{display:none;position:absolute;top:64px;left:0;right:0;background:var(--white);flex-direction:column;padding:16px;box-shadow:var(--shadow);gap:0}
  .nav.open{display:flex}
  .nav li{padding:10px 0;border-bottom:1px solid #eee}
  .menu-toggle{display:block}
  .hero h1{font-size:1.8rem}
  .hero{padding:56px 0}
  .btn-outline{margin-left:0;margin-top:12px}
  .features-grid,.testimonials-grid,.version-cards,.sys-req-grid,.security-grid,.stats-grid,.platform-grid,.article-list-grid{grid-template-columns:1fr}
  .footer-grid{grid-template-columns:1fr}
}