*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
html{font-size:16px;-webkit-text-size-adjust:100%}
body{font-family:"PingFang SC","Microsoft YaHei","Segoe UI",sans-serif;background:#f3f4f6;color:#1f2937;line-height:1.65}
img{max-width:100%;height:auto;display:block}
a{color:#2563eb;text-decoration:none}
a:hover{text-decoration:underline}
ul{list-style:none}
.container{width:min(1100px,92vw);margin:0 auto}

.site-header{position:sticky;top:0;z-index:100;background:#fff;border-bottom:1px solid #e5e7eb}
.header-inner{display:flex;align-items:center;justify-content:space-between;padding:.75rem 0;gap:1rem}
.logo{font-weight:800;font-size:1.05rem;color:#111827;display:flex;align-items:center;gap:.5rem}
.logo-badge{background:#2563eb;color:#fff;font-size:.62rem;font-weight:800;padding:.2rem .45rem;border-radius:4px;letter-spacing:.04em}
.nav-main{display:flex;flex-wrap:wrap;gap:.35rem 1.2rem;font-size:.88rem}
.nav-main a{color:#6b7280;font-weight:600}
.nav-main a.active,.nav-main a:hover{color:#2563eb;text-decoration:none}
.btn-nav{display:inline-block;background:#2563eb;color:#fff!important;padding:.48rem 1.15rem;font-weight:700;font-size:.85rem;border-radius:6px;text-decoration:none!important}
.btn-nav:hover{background:#1d4ed8}

.section{padding:3rem 0}
.section-title{font-size:clamp(1.2rem,3vw,1.55rem);font-weight:800;color:#111827;margin-bottom:.35rem}
.section-lead{color:#6b7280;font-size:.9rem;margin-bottom:1.65rem;max-width:620px}

.footer{background:#111827;color:#9ca3af;padding:2.5rem 0 0;font-size:.86rem}
.footer-grid{display:grid;grid-template-columns:1.4fr 1fr 1fr;gap:2rem;margin-bottom:2rem}
.footer h3{font-size:.9rem;color:#fff;margin-bottom:.65rem;font-weight:800}
.footer a{color:#9ca3af}
.footer-links{display:flex;flex-wrap:wrap;gap:.4rem 1rem}
.footer-bottom{border-top:1px solid #374151;padding-top:1rem;text-align:center;color:#6b7280;font-size:.78rem}

.faq-list{display:flex;flex-direction:column;gap:.45rem}
.faq-item{background:#fff;border:1px solid #e5e7eb;border-radius:8px;overflow:hidden}
.faq-q{width:100%;text-align:left;padding:.95rem 1.1rem;font-weight:700;font-size:.9rem;background:transparent;border:none;cursor:pointer;color:#111827;display:flex;justify-content:space-between;align-items:center;font-family:inherit}
.faq-q::after{content:"+";font-size:1.15rem;color:#9ca3af;font-weight:400}
.faq-item.open .faq-q::after{content:"−"}
.faq-a{display:none;padding:0 1.1rem .95rem;font-size:.86rem;color:#6b7280;line-height:1.65}
.faq-item.open .faq-a{display:block}

.btn-primary{display:inline-block;background:#2563eb;color:#fff!important;padding:.65rem 1.35rem;font-weight:700;font-size:.9rem;border-radius:6px;text-decoration:none!important}
.btn-primary:hover{background:#1d4ed8}
.btn-secondary{display:inline-block;color:#2563eb;border:2px solid #2563eb;padding:.6rem 1.25rem;font-weight:600;font-size:.9rem;border-radius:6px;text-decoration:none!important;background:#fff}
.btn-secondary:hover{background:#eff6ff}

.tag{display:inline-block;background:#eff6ff;color:#2563eb;font-size:.72rem;font-weight:700;padding:.2rem .55rem;border-radius:4px;margin-right:.35rem}

@media(max-width:768px){
  .header-inner{flex-wrap:wrap}
  .footer-grid{grid-template-columns:1fr}
}