/* 小蓝APP下载入口 - 全局样式 */
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
:root{
  --primary:#2188FF;
  --primary-dark:#0D6EFD;
  --accent:#FF6B35;
  --bg:#F5F8FC;
  --card:#FFFFFF;
  --text:#1A1A2E;
  --text-muted:#6B7280;
  --border:#E5E7EB;
  --shadow:0 2px 12px rgba(33,136,255,.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);text-decoration:underline}
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:100}
.header-inner{display:flex;align-items:center;justify-content:space-between;padding:14px 0;gap:16px}
.logo-wrap{display:flex;align-items:center;gap:10px;flex-shrink:0}
.logo-wrap img{width:44px;height:44px;border-radius:10px}
.logo-text{font-size:1.15rem;font-weight:700;color:var(--text);white-space:nowrap}
.logo-text span{color:var(--primary)}
.nav-main{display:flex;gap:6px;flex-wrap:wrap}
.nav-main a{padding:8px 14px;border-radius:8px;color:var(--text);font-size:.95rem;font-weight:500}
.nav-main a:hover,.nav-main a.active{background:rgba(33,136,255,.1);color:var(--primary);text-decoration:none}
.menu-toggle{display:none;background:none;border:none;font-size:1.5rem;cursor:pointer;color:var(--text)}

/* Hero */
.hero{background:linear-gradient(135deg,#2188FF 0%,#4DA3FF 50%,#7EC8FF 100%);color:#fff;padding:60px 0 70px;text-align:center}
.hero h1{font-size:2rem;margin-bottom:16px;line-height:1.3}
.hero-desc{font-size:1.05rem;opacity:.95;max-width:700px;margin:0 auto 28px}
.btn-group{display:flex;gap:14px;justify-content:center;flex-wrap:wrap}
.btn{display:inline-flex;align-items:center;gap:8px;padding:14px 28px;border-radius:50px;font-size:1rem;font-weight:600;border:none;cursor:pointer;transition:transform .2s,box-shadow .2s}
.btn:hover{transform:translateY(-2px);box-shadow:0 6px 20px rgba(0,0,0,.15)}
.btn-primary{background:#fff;color:var(--primary)}
.btn-outline{background:transparent;color:#fff;border:2px solid rgba(255,255,255,.8)}
.btn-accent{background:var(--accent);color:#fff}

/* Sections */
section{padding:56px 0}
.section-title{text-align:center;margin-bottom:40px}
.section-title h2{font-size:1.75rem;margin-bottom:10px;color:var(--text)}
.section-title p{color:var(--text-muted);max-width:600px;margin:0 auto}
.section-alt{background:var(--card)}

/* Feature Grid */
.feature-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:24px}
.feature-card{background:var(--card);border-radius:var(--radius);overflow:hidden;box-shadow:var(--shadow);transition:transform .25s}
.feature-card:hover{transform:translateY(-4px)}
.feature-card img{width:100%;aspect-ratio:9/16;object-fit:cover;object-position:top}
.feature-card-body{padding:18px}
.feature-card h3{font-size:1.05rem;margin-bottom:8px}
.feature-card p{font-size:.9rem;color:var(--text-muted);line-height:1.6}

/* Content blocks */
.content-block{display:grid;grid-template-columns:1fr 1fr;gap:40px;align-items:center;margin-bottom:48px}
.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:1.35rem;margin-bottom:14px;color:var(--primary)}
.content-block p{margin-bottom:12px;color:var(--text-muted)}

/* Steps */
.steps{display:grid;grid-template-columns:repeat(4,1fr);gap:20px}
.step-card{background:var(--card);border-radius:var(--radius);padding:24px;text-align:center;box-shadow:var(--shadow)}
.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 14px;font-size:1.1rem}
.step-card h4{margin-bottom:8px;font-size:1rem}
.step-card p{font-size:.88rem;color:var(--text-muted)}

/* 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 22px;font-weight:600;cursor:pointer;display:flex;justify-content:space-between;align-items:center}
.faq-q::after{content:"+";font-size:1.3rem;color:var(--primary)}
.faq-a{padding:0 22px 18px;color:var(--text-muted);font-size:.95rem;display:none}
.faq-item.open .faq-a{display:block}
.faq-item.open .faq-q::after{content:"−"}

/* Article (sub pages) */
.article-page{padding:40px 0 60px}
.article-page h1{font-size:1.8rem;margin-bottom:24px;padding-bottom:16px;border-bottom:2px solid var(--primary)}
.article-page h2{font-size:1.3rem;margin:28px 0 12px;color:var(--primary)}
.article-page h3{font-size:1.1rem;margin:20px 0 10px}
.article-page p,.article-page li{margin-bottom:12px;color:var(--text-muted);line-height:1.8}
.article-page ul,.article-page ol{padding-left:24px;margin-bottom:16px}
.article-page .meta{color:var(--text-muted);font-size:.9rem;margin-bottom:24px}

/* 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)}
.gallery-item img{width:100%;aspect-ratio:9/16;object-fit:cover;object-position:top}

/* CTA */
.cta-section{background:linear-gradient(135deg,var(--primary),#4DA3FF);color:#fff;text-align:center;padding:50px 20px;border-radius:var(--radius);margin:0 20px}
.cta-section h2{margin-bottom:12px}
.cta-section p{opacity:.9;margin-bottom:24px}

/* Footer */
.site-footer{background:#1A1A2E;color:rgba(255,255,255,.75);padding:48px 0 24px;margin-top:60px}
.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 a{color:rgba(255,255,255,.65);display:block;margin-bottom:8px;font-size:.9rem}
.footer-grid a:hover{color:#fff;text-decoration:none}
.footer-bottom{text-align:center;padding-top:24px;border-top:1px solid rgba(255,255,255,.1);font-size:.85rem}

/* 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{margin:16px 0 12px}
.error-page p{color:var(--text-muted);margin-bottom:24px}

/* Breadcrumb */
.breadcrumb{padding:14px 0;font-size:.88rem;color:var(--text-muted)}
.breadcrumb a{color:var(--text-muted)}
.breadcrumb span{margin:0 6px}

/* Internal links highlight */
.internal-links{background:var(--card);border-radius:var(--radius);padding:24px;margin:32px 0;box-shadow:var(--shadow)}
.internal-links h3{font-size:1.05rem;margin-bottom:12px}
.internal-links a{margin-right:16px;font-size:.92rem}

/* 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-main{display:none;position:absolute;top:100%;left:0;right:0;background:var(--card);flex-direction:column;padding:12px 20px;box-shadow:var(--shadow)}
  .nav-main.open{display:flex}
  .menu-toggle{display:block}
  .hero h1{font-size:1.5rem}
  .hero{padding:40px 0 50px}
  .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}
}