*,*::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:#ececec;color:#2a2a2a;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(1140px,92vw);margin:0 auto}
.mono{font-family:Consolas,"Courier New",monospace}

.site-header{position:sticky;top:0;z-index:100;background:#3d3d3d;border-bottom:2px solid #2563eb}
.header-inner{display:flex;align-items:center;justify-content:space-between;padding:.65rem 0;gap:1rem}
.logo{font-weight:700;font-size:1.05rem;color:#f5f5f5;letter-spacing:.06em;text-transform:uppercase}
.logo i{font-style:normal;color:#2563eb}
.nav-main{display:flex;flex-wrap:wrap;gap:.35rem 1.1rem;font-size:.86rem}
.nav-main a{color:#aaa;font-weight:600}
.nav-main a.active,.nav-main a:hover{color:#fff;text-decoration:none}
.btn-nav{display:inline-block;background:#2563eb;color:#fff!important;padding:.42rem .95rem;font-weight:700;font-size:.82rem;text-decoration:none!important}
.btn-nav:hover{background:#1d4ed8}

.section{padding:3.25rem 0}
.section-title{font-size:clamp(1.25rem,3vw,1.6rem);font-weight:800;margin-bottom:.4rem;color:#2a2a2a;text-transform:uppercase;letter-spacing:.04em}
.section-lead{color:#666;font-size:.9rem;margin-bottom:1.75rem;max-width:600px}

.footer{background:#2a2a2a;color:#999;padding:2.25rem 0 0;font-size:.84rem}
.footer-grid{display:grid;grid-template-columns:1.4fr 1fr 1fr;gap:2rem;padding-bottom:1.75rem}
.footer h3{font-size:.88rem;color:#ccc;margin-bottom:.65rem;text-transform:uppercase;letter-spacing:.06em}
.footer a{color:#888}
.footer-links{display:flex;flex-wrap:wrap;gap:.4rem 1rem}
.footer-bottom{padding:.85rem 0;text-align:center;color:#666;font-size:.76rem;border-top:1px solid #444}

@media(max-width:768px){
  .header-inner{flex-direction:column;align-items:flex-start}
  .footer-grid{grid-template-columns:1fr}
}