header{position:sticky;top:0;z-index:50;background:rgba(7,10,18,.6);backdrop-filter:blur(12px);border-bottom:1px solid var(--line)}.nav{display:flex;align-items:center;justify-content:space-between;padding:14px 0}.brand{display:flex;gap:12px;align-items:center;font-weight:800}.mark{width:38px;height:38px;border-radius:14px;background:radial-gradient(circle at 30% 30%,#37f2d4,transparent 60%);border:1px solid var(--line)}footer{border-top:1px solid var(--line);padding:28px 0;margin-top:40px;color:var(--muted);font-size:13px}