:root{--hdr-bg:rgba(10, 12, 18, 0.92);--hdr-bg-scrolled:rgba(10, 12, 18, 0.65);--hdr-border:rgba(255, 255, 255, 0.1);--text:#fff;--text-dim:#cbd5e1;--accent:#60a5fa;--shadow:0 2px 14px rgba(0, 0, 0, 0.45)}.site-header{position:sticky;top:0;z-index:50;backdrop-filter:none;-webkit-backdrop-filter:none;background:var(--hdr-bg);border-bottom:1px solid var(--hdr-border);box-shadow:var(--shadow);transition:background .25s ease,backdrop-filter .25s ease,-webkit-backdrop-filter .25s ease,border-color .25s ease}.site-header.is-scrolled{background:var(--hdr-bg-scrolled);backdrop-filter:saturate(140%)blur(8px);-webkit-backdrop-filter:saturate(140%)blur(8px);border-bottom-color:rgba(255,255,255,.14)}.site-header__inner{max-width:980px;margin:0 auto;padding:10px 14px;display:flex;align-items:center;justify-content:space-between}.brand{display:inline-block;text-decoration:none;color:var(--text);font-family:ui-monospace,SFMono-Regular,Menlo,Monaco,Consolas,courier new,monospace;font-weight:800;letter-spacing:.08em;text-shadow:0 0 8px rgba(96,165,250,.15)}.site-nav{display:flex;gap:14px}.nav-link{position:relative;display:inline-block;padding:6px 10px;text-decoration:none;color:var(--text);font-weight:600;border:1px solid transparent;border-radius:10px;transition:border-color .18s ease,transform .12s ease,background .18s ease,color .18s ease}.nav-link:hover{border-color:var(--hdr-border);transform:translateY(-1px);background:rgba(255,255,255,4%)}.nav-link:focus-visible{outline:2px solid var(--accent);outline-offset:2px;border-radius:10px}@media(max-width:720px){.site-header__inner{padding:8px 12px}.nav-link{padding:6px 8px}}