*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
:root{
  --primary:#1a6fd4;
  --primary-dark:#0d4a9e;
  --accent:#e8382a;
  --text:#1a1a2e;
  --text-light:#5a6278;
  --bg:#f5f7fb;
  --white:#fff;
  --radius:12px;
  --shadow:0 4px 24px rgba(26,111,212,.08);
}
html{scroll-behavior:smooth}
body{font-family:"PingFang SC","Microsoft YaHei","Helvetica Neue",Arial,sans-serif;color:var(--text);background:var(--bg);line-height:1.7;font-size:16px}
a{color:var(--primary);text-decoration:none;transition:color .2s}
a:hover{color:var(--primary-dark)}
img{max-width:100%;display:block}
.container{max-width:1140px;margin:0 auto;padding:0 20px}

/* Header */
.site-header{background:var(--white);box-shadow:0 1px 8px rgba(0,0,0,.06);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:20px;font-weight:700;color:var(--text)}
.logo-icon{width:36px;height:36px;background:linear-gradient(135deg,var(--primary),var(--accent));border-radius:8px;display:flex;align-items:center;justify-content:center;color:#fff;font-weight:800;font-size:18px}
.nav{display:flex;gap:28px;align-items:center}
.nav a{color:var(--text-light);font-size:15px;font-weight:500}
.nav a:hover,.nav a.active{color:var(--primary)}
.btn-download{background:var(--accent);color:#fff!important;padding:8px 22px;border-radius:20px;font-weight:600;font-size:14px}
.btn-download:hover{background:#c42e22;color:#fff!important}
.menu-toggle{display:none;background:none;border:none;font-size:24px;cursor:pointer;color:var(--text)}

/* Hero */
.hero{background:linear-gradient(135deg,#0d4a9e 0%,#1a6fd4 50%,#3a8fd8 100%);color:#fff;padding:80px 0 90px;text-align:center;position:relative;overflow:hidden}
.hero::after{content:"";position:absolute;top:-50%;right:-20%;width:600px;height:600px;background:rgba(255,255,255,.05);border-radius:50%}
.hero-badge{display:inline-block;background:rgba(255,255,255,.15);padding:6px 18px;border-radius:20px;font-size:13px;margin-bottom:20px;backdrop-filter:blur(4px)}
.hero h1{font-size:42px;font-weight:800;line-height:1.3;margin-bottom:16px}
.hero-sub{font-size:18px;opacity:.9;margin-bottom:12px}
.hero-stats{font-size:15px;opacity:.8;margin-bottom:32px}
.hero-actions{display:flex;gap:16px;justify-content:center;flex-wrap:wrap}
.btn-primary{background:var(--accent);color:#fff;padding:14px 36px;border-radius:28px;font-size:16px;font-weight:600;border:none;cursor:pointer;display:inline-block}
.btn-primary:hover{background:#c42e22;color:#fff}
.btn-outline{background:transparent;color:#fff;padding:14px 36px;border-radius:28px;font-size:16px;font-weight:600;border:2px solid rgba(255,255,255,.6);display:inline-block}
.btn-outline:hover{background:rgba(255,255,255,.1);color:#fff}

/* Sections */
section{padding:72px 0}
.section-title{text-align:center;margin-bottom:48px}
.section-title h2{font-size:32px;font-weight:700;margin-bottom:10px}
.section-title p{color:var(--text-light);font-size:16px}
.section-label{display:inline-block;color:var(--primary);font-size:13px;font-weight:600;letter-spacing:1px;margin-bottom:8px}

/* Steps */
.steps{display:grid;grid-template-columns:repeat(3,1fr);gap:32px}
.step-card{background:var(--white);border-radius:var(--radius);padding:36px 28px;text-align:center;box-shadow:var(--shadow)}
.step-num{display:inline-block;width:48px;height:48px;line-height:48px;background:var(--primary);color:#fff;border-radius:50%;font-size:18px;font-weight:700;margin-bottom:16px}
.step-card h3{font-size:18px;margin-bottom:10px}
.step-card p{color:var(--text-light);font-size:14px}

/* Features */
.features-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:24px}
.feature-card{background:var(--white);border-radius:var(--radius);padding:28px 22px;box-shadow:var(--shadow);transition:transform .2s}
.feature-card:hover{transform:translateY(-4px)}
.feature-icon{font-size:32px;margin-bottom:14px}
.feature-card h3{font-size:16px;margin-bottom:8px}
.feature-card p{color:var(--text-light);font-size:13px;line-height:1.6}
.feature-tag{display:inline-block;background:#eef4fc;color:var(--primary);font-size:12px;padding:3px 10px;border-radius:10px;margin-top:10px}

/* Trust */
.trust-section{background:var(--white)}
.trust-list{max-width:800px;margin:0 auto 40px}
.trust-list li{list-style:none;padding:12px 0 12px 28px;position:relative;font-size:15px;border-bottom:1px solid #eef0f5}
.trust-list li::before{content:"✓";position:absolute;left:0;color:var(--primary);font-weight:700}
.testimonials{display:grid;grid-template-columns:repeat(3,1fr);gap:24px}
.testimonial{background:var(--bg);border-radius:var(--radius);padding:28px;font-size:14px;color:var(--text-light)}
.testimonial p{margin-bottom:16px;font-style:italic;line-height:1.7}
.testimonial cite{font-style:normal;font-weight:600;color:var(--text);font-size:13px}

/* Why */
.why-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:28px}
.why-card{background:var(--white);border-radius:var(--radius);padding:32px;box-shadow:var(--shadow)}
.why-card h3{font-size:17px;margin-bottom:10px;color:var(--primary)}
.why-card p{color:var(--text-light);font-size:14px}
.quote-block{background:linear-gradient(135deg,#eef4fc,#f5f7fb);border-left:4px solid var(--primary);padding:24px 28px;border-radius:0 var(--radius) var(--radius) 0;margin-top:40px;font-size:15px;color:var(--text-light)}

/* 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-q{padding:20px 24px;cursor:pointer;font-weight:600;font-size:15px;display:flex;justify-content:space-between;align-items:center;user-select:none}
.faq-q::after{content:"+";font-size:20px;color:var(--primary);transition:transform .2s}
.faq-item.open .faq-q::after{transform:rotate(45deg)}
.faq-a{max-height:0;overflow:hidden;transition:max-height .3s ease;padding:0 24px;color:var(--text-light);font-size:14px;line-height:1.7}
.faq-item.open .faq-a{max-height:300px;padding:0 24px 20px}

/* Download page */
.download-hero{background:linear-gradient(135deg,#0d4a9e,#1a6fd4);color:#fff;padding:60px 0;text-align:center}
.download-hero h1{font-size:36px;margin-bottom:12px}
.download-badges{display:flex;gap:16px;justify-content:center;flex-wrap:wrap;margin-top:20px;font-size:14px;opacity:.9}
.download-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:28px;margin-top:48px}
.dl-card{background:var(--white);border-radius:var(--radius);padding:32px;box-shadow:var(--shadow)}
.dl-card h2{font-size:20px;margin-bottom:6px;display:flex;align-items:center;gap:10px}
.dl-card .platform{font-size:13px;color:var(--text-light);margin-bottom:16px}
.dl-card p{color:var(--text-light);font-size:14px;margin-bottom:16px}
.dl-meta{font-size:13px;color:var(--text-light);margin-bottom:20px;line-height:1.8}
.dl-meta span{display:block}
.btn-dl{background:var(--primary);color:#fff;padding:12px 28px;border-radius:8px;font-weight:600;font-size:14px;display:inline-block;border:none;cursor:pointer}
.btn-dl:hover{background:var(--primary-dark);color:#fff}
.changelog{font-size:12px;color:var(--text-light);margin-top:14px;padding-top:14px;border-top:1px solid #eef0f5}
.security-box{background:var(--white);border-radius:var(--radius);padding:36px;box-shadow:var(--shadow);margin-top:48px;text-align:center}
.security-box h3{margin-bottom:12px}

/* Articles */
.article-hero{background:linear-gradient(135deg,#0d4a9e,#1a6fd4);color:#fff;padding:48px 0}
.article-hero h1{font-size:30px;margin-bottom:8px}
.article-meta{font-size:14px;opacity:.85}
.article-body{background:var(--white);border-radius:var(--radius);padding:40px 48px;box-shadow:var(--shadow);margin:-30px auto 40px;max-width:800px;position:relative}
.article-body h2{font-size:22px;margin:28px 0 12px;color:var(--text)}
.article-body h3{font-size:18px;margin:20px 0 10px}
.article-body p{margin-bottom:16px;color:var(--text-light);line-height:1.8}
.article-body ul,.article-body ol{margin:0 0 16px 24px;color:var(--text-light)}
.article-body li{margin-bottom:6px}
.article-list{display:grid;grid-template-columns:repeat(3,1fr);gap:24px}
.article-card{background:var(--white);border-radius:var(--radius);overflow:hidden;box-shadow:var(--shadow);transition:transform .2s}
.article-card:hover{transform:translateY(-3px)}
.article-card-body{padding:24px}
.article-card h3{font-size:16px;margin-bottom:8px;line-height:1.5}
.article-card p{font-size:13px;color:var(--text-light);margin-bottom:12px}
.article-card .date{font-size:12px;color:var(--primary)}
.daily-update-badge{display:inline-block;background:#e8f5e9;color:#2e7d32;font-size:12px;padding:3px 10px;border-radius:10px;margin-left:8px}

/* Footer */
.site-footer{background:#1a1a2e;color:rgba(255,255,255,.7);padding:48px 0 24px;font-size:14px}
.footer-grid{display:grid;grid-template-columns:2fr 1fr 1fr 1fr;gap:32px;margin-bottom:32px}
.footer-grid h4{color:#fff;font-size:15px;margin-bottom:14px}
.footer-grid a{color:rgba(255,255,255,.6);display:block;margin-bottom:8px;font-size:13px}
.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:13px}

/* Breadcrumb */
.breadcrumb{font-size:13px;color:var(--text-light);margin-bottom:20px}
.breadcrumb a{color:var(--text-light)}
.breadcrumb a:hover{color:var(--primary)}

/* Responsive */
@media(max-width:992px){
  .features-grid{grid-template-columns:repeat(2,1fr)}
  .testimonials,.why-grid{grid-template-columns:1fr}
  .download-grid{grid-template-columns:1fr}
  .article-list{grid-template-columns:1fr 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:20px;box-shadow:var(--shadow);gap:16px}
  .nav.open{display:flex}
  .menu-toggle{display:block}
  .hero h1{font-size:28px}
  .steps{grid-template-columns:1fr}
  .features-grid{grid-template-columns:1fr}
  .article-list{grid-template-columns:1fr}
  .footer-grid{grid-template-columns:1fr}
  .article-body{padding:24px}
}