*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
:root{--primary:#1a8cff;--primary-dark:#0d6efd;--accent:#ff6b35;--bg:#f5f8fc;--card:#fff;--text:#1a1a2e;--text-light:#5a6270;--border:#e2e8f0;--shadow:0 2px 12px rgba(0,0,0,.08);--radius:12px;--max-w:1200px}
html{scroll-behavior:smooth;font-size:16px}
body{font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Hiragino Sans GB","Microsoft YaHei",sans-serif;color:var(--text);background:var(--bg);line-height:1.7}
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-w);margin:0 auto;padding:0 20px}

/* Header */
.site-header{background:var(--card);box-shadow:var(--shadow);position:sticky;top:0;z-index:1000}
.header-inner{display:flex;align-items:center;justify-content:space-between;padding:12px 20px;max-width:var(--max-w);margin:0 auto}
.logo-link{display:flex;align-items:center;gap:10px;font-size:1.25rem;font-weight:700;color:var(--text)}
.logo-link img{width:40px;height:40px;border-radius:10px}
.nav-desktop{display:flex;gap:28px;list-style:none}
.nav-desktop a{color:var(--text);font-weight:500;font-size:.95rem}
.nav-desktop a:hover,.nav-desktop a.active{color:var(--primary)}
.nav-toggle{display:none;background:none;border:none;cursor:pointer;padding:8px}
.nav-toggle span{display:block;width:24px;height:2px;background:var(--text);margin:6px 0;transition:.3s}
.nav-mobile{display:none;position:absolute;top:100%;left:0;right:0;background:var(--card);box-shadow:var(--shadow);list-style:none;padding:16px 0}
.nav-mobile.open{display:block}
.nav-mobile li a{display:block;padding:12px 24px;color:var(--text);font-weight:500}
.nav-mobile li a:hover{background:var(--bg);color:var(--primary)}

/* Hero */
.hero{background:linear-gradient(135deg,#1a8cff 0%,#0d6efd 50%,#0056b3 100%);color:#fff;padding:60px 20px 80px;text-align:center;position:relative;overflow:hidden}
.hero::after{content:"";position:absolute;bottom:-2px;left:0;right:0;height:60px;background:var(--bg);border-radius:50% 50% 0 0 / 100% 100% 0 0}
.hero h1{font-size:2.2rem;margin-bottom:16px;line-height:1.3}
.hero p{font-size:1.1rem;opacity:.92;max-width:700px;margin:0 auto 28px}
.hero-btns{display:flex;gap:16px;justify-content:center;flex-wrap:wrap}
.btn{display:inline-flex;align-items:center;gap:8px;padding:14px 32px;border-radius:50px;font-weight:600;font-size:1rem;border:none;cursor:pointer;transition:transform .2s,box-shadow .2s}
.btn:hover{transform:translateY(-2px)}
.btn-primary{background:#fff;color:var(--primary);box-shadow:0 4px 15px rgba(0,0,0,.15)}
.btn-outline{background:transparent;color:#fff;border:2px solid rgba(255,255,255,.7)}
.btn-accent{background:var(--accent);color:#fff;box-shadow:0 4px 15px rgba(255,107,53,.3)}

/* Sections */
section{padding:60px 0}
.section-title{text-align:center;margin-bottom:48px}
.section-title h2{font-size:1.8rem;margin-bottom:12px;color:var(--text)}
.section-title p{color:var(--text-light);max-width:600px;margin:0 auto}
.section-title .line{width:50px;height:4px;background:var(--primary);margin:16px auto 0;border-radius:2px}

/* Feature Grid */
.feature-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:28px}
.feature-card{background:var(--card);border-radius:var(--radius);padding:32px 24px;text-align:center;box-shadow:var(--shadow);transition:transform .3s}
.feature-card:hover{transform:translateY(-4px)}
.feature-icon{width:64px;height:64px;background:linear-gradient(135deg,var(--primary),#4dabff);border-radius:16px;display:flex;align-items:center;justify-content:center;margin:0 auto 20px;font-size:1.8rem}
.feature-card h3{font-size:1.15rem;margin-bottom:10px}
.feature-card p{color:var(--text-light);font-size:.92rem}

/* Content Block */
.content-block{display:grid;grid-template-columns:1fr 1fr;gap:40px;align-items:center;margin-bottom:60px}
.content-block.reverse{direction:rtl}
.content-block.reverse>*{direction:ltr}
.content-block img{border-radius:var(--radius);box-shadow:var(--shadow)}
.content-block h3{font-size:1.4rem;margin-bottom:16px;color:var(--primary)}
.content-block p{color:var(--text-light);margin-bottom:12px;font-size:.95rem}
.content-block ul{padding-left:20px;color:var(--text-light);font-size:.95rem}
.content-block ul li{margin-bottom:8px}

/* Download Steps */
.steps{display:grid;grid-template-columns:repeat(4,1fr);gap:24px}
.step-card{background:var(--card);border-radius:var(--radius);padding:28px 20px;text-align:center;box-shadow:var(--shadow);position:relative}
.step-num{width:40px;height:40px;background:var(--primary);color:#fff;border-radius:50%;display:flex;align-items:center;justify-content:center;font-weight:700;margin:0 auto 16px;font-size:1.1rem}
.step-card h4{margin-bottom:8px;font-size:1rem}
.step-card p{color:var(--text-light);font-size:.88rem}

/* FAQ */
.faq-list{max-width:800px;margin:0 auto}
.faq-item{background:var(--card);border-radius:var(--radius);margin-bottom:12px;box-shadow:var(--shadow);overflow:hidden}
.faq-q{padding:18px 24px;font-weight:600;cursor:pointer;display:flex;justify-content:space-between;align-items:center}
.faq-q::after{content:"+";font-size:1.4rem;color:var(--primary);transition:transform .3s}
.faq-item.open .faq-q::after{transform:rotate(45deg)}
.faq-a{padding:0 24px;max-height:0;overflow:hidden;transition:max-height .3s,padding .3s;color:var(--text-light);font-size:.93rem}
.faq-item.open .faq-a{max-height:300px;padding:0 24px 18px}

/* Gallery */
.gallery-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:16px}
.gallery-item{border-radius:var(--radius);overflow:hidden;box-shadow:var(--shadow);position:relative}
.gallery-item img{width:100%;aspect-ratio:9/16;object-fit:cover}
.gallery-item figcaption{position:absolute;bottom:0;left:0;right:0;background:linear-gradient(transparent,rgba(0,0,0,.7));color:#fff;padding:20px 12px 10px;font-size:.82rem;text-align:center}

/* Article (sub pages) */
.page-hero{background:linear-gradient(135deg,var(--primary),#0056b3);color:#fff;padding:48px 20px;text-align:center}
.page-hero h1{font-size:1.8rem;margin-bottom:8px}
.page-hero p{opacity:.85;font-size:.95rem}
.article-content{max-width:860px;margin:0 auto;padding:48px 20px}
.article-content h2{font-size:1.35rem;margin:32px 0 16px;color:var(--primary)}
.article-content h3{font-size:1.1rem;margin:24px 0 12px}
.article-content p,.article-content li{color:var(--text-light);margin-bottom:12px;font-size:.95rem}
.article-content ul,.article-content ol{padding-left:24px;margin-bottom:16px}

/* Error Pages */
.error-page{min-height:70vh;display:flex;align-items:center;justify-content:center;text-align:center;padding:40px 20px}
.error-page h1{font-size:5rem;color:var(--primary);line-height:1}
.error-page h2{font-size:1.5rem;margin:16px 0}
.error-page p{color:var(--text-light);margin-bottom:24px}

/* Footer */
.site-footer{background:#0f1923;color:#a0aec0;padding:48px 20px 24px}
.footer-grid{display:grid;grid-template-columns:2fr 1fr 1fr 1fr;gap:32px;max-width:var(--max-w);margin:0 auto 32px}
.footer-brand img{width:48px;border-radius:10px;margin-bottom:12px}
.footer-brand p{font-size:.88rem;line-height:1.6}
.footer-col h4{color:#fff;margin-bottom:16px;font-size:.95rem}
.footer-col ul{list-style:none}
.footer-col li{margin-bottom:8px}
.footer-col a{color:#a0aec0;font-size:.88rem}
.footer-col a:hover{color:#fff}
.footer-bottom{text-align:center;padding-top:24px;border-top:1px solid #1e2d3d;font-size:.82rem;max-width:var(--max-w);margin:0 auto}

/* Breadcrumb */
.breadcrumb{padding:16px 0;font-size:.85rem;color:var(--text-light)}
.breadcrumb a{color:var(--text-light)}
.breadcrumb a:hover{color:var(--primary)}

/* Responsive */
@media(max-width:992px){
  .feature-grid{grid-template-columns:repeat(2,1fr)}
  .content-block{grid-template-columns:1fr}
  .content-block.reverse{direction:ltr}
  .steps{grid-template-columns:repeat(2,1fr)}
  .gallery-grid{grid-template-columns:repeat(3,1fr)}
  .footer-grid{grid-template-columns:1fr 1fr}
}
@media(max-width:768px){
  .nav-desktop{display:none}
  .nav-toggle{display:block}
  .hero h1{font-size:1.6rem}
  .hero{padding:40px 16px 60px}
  .feature-grid{grid-template-columns:1fr}
  .steps{grid-template-columns:1fr}
  .gallery-grid{grid-template-columns:repeat(2,1fr)}
  .footer-grid{grid-template-columns:1fr}
  section{padding:40px 0}
  .section-title h2{font-size:1.4rem}
}