*,*::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",sans-serif;background:#061018;color:#b8d4e8;line-height:1.65}
img{max-width:100%;height:auto;display:block}
a{color:#00e5ff;text-decoration:none}
a:hover{text-decoration:underline}
ul{list-style:none}
.container{width:min(1120px,92vw);margin:0 auto}

.site-header{position:sticky;top:0;z-index:100;background:#041018;border-bottom:2px solid #00e5ff}
.header-inner{display:flex;align-items:center;justify-content:space-between;padding:.7rem 0;gap:1rem}
.logo{font-weight:800;font-size:1.05rem;color:#e8f4fc;display:flex;align-items:center;gap:.5rem}
.logo-fiber{width:24px;height:4px;background:linear-gradient(90deg,#00e5ff,#7b68ee,#00e5ff);border-radius:2px;position:relative}
.logo-fiber::after{content:"";position:absolute;right:-4px;top:-3px;width:10px;height:10px;border-radius:50%;background:#00e5ff}
.nav-main{display:flex;flex-wrap:wrap;gap:.35rem 1.1rem;font-size:.88rem}
.nav-main a{color:#6a8aa8;font-weight:600}
.nav-main a.active,.nav-main a:hover{color:#00e5ff;text-decoration:none}
.btn-nav{display:inline-block;background:#00e5ff;color:#041018!important;padding:.45rem 1.05rem;font-weight:800;font-size:.85rem;text-decoration:none!important}
.btn-nav:hover{background:#4df0ff}

.section{padding:3.5rem 0}
.section-title{font-size:clamp(1.28rem,3vw,1.65rem);font-weight:800;margin-bottom:.45rem;color:#e8f4fc}
.section-lead{color:#6a8aa8;font-size:.92rem;margin-bottom:1.85rem;max-width:640px}

.footer{background:#020810;border-top:2px solid #1a4a6a;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:.92rem;color:#00e5ff;margin-bottom:.7rem}
.footer a{color:#6a8aa8}
.footer-links{display:flex;flex-wrap:wrap;gap:.4rem 1rem}
.footer-bottom{border-top:1px solid #0a2030;padding-top:1rem;text-align:center;color:#4a6a80;font-size:.78rem}

.faq-list{display:flex;flex-direction:column;gap:.5rem}
.faq-item{background:#0a1828;border:1px solid #1a4a6a;border-left:3px solid #00e5ff}
.faq-q{width:100%;text-align:left;padding:1rem 1.15rem;font-weight:700;font-size:.92rem;background:transparent;border:none;cursor:pointer;color:#e8f4fc;display:flex;justify-content:space-between;align-items:center;font-family:inherit}
.faq-q::after{content:"▸";font-size:.85rem;color:#00e5ff;transition:transform .2s}
.faq-item.open .faq-q::after{transform:rotate(90deg)}
.faq-a{display:none;padding:0 1.15rem 1rem;font-size:.88rem;color:#6a8aa8;line-height:1.7}
.faq-item.open .faq-a{display:block}

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