:root{--bg:#0b1220;--panel:#112a3b;--text:#e8eefc;--muted:#a9b4cf;--brand:#3b82f6;--ok:#22c55e;--danger:#ef4444;--radius:14px;--shadow:0 12px 30px rgba(0,0,0,.35)}*{box-sizing:border-box}body,html{margin:0;padding:0;background:radial-gradient(1200px 800px at 20% -10%,#13203a 0,#0b1220 40%,#0b1220 100%);color:var(--text);font-family:ui-sans-serif,system-ui,Segoe UI,Roboto,Helvetica,Arial,sans-serif;min-height:100%}a{color:var(--brand);text-decoration:none}a:hover{text-decoration:underline}.shell{min-height:100vh;display:grid;grid-template-rows:auto 1fr auto}.topbar{position:-webkit-sticky;position:sticky;top:0;-webkit-backdrop-filter:blur(6px);backdrop-filter:blur(6px);background:rgba(0,0,0,.25);border-bottom:1px solid hsla(0,0%,100%,.06)}.brand{font-weight:700;letter-spacing:.5px;padding:14px 20px}.main{display:grid;place-items:center;padding:32px 16px}.footer{text-align:center;padding:14px 20px;opacity:.8}.container{max-width:960px;margin:0 auto}.card{background:var(--panel);border:1px solid hsla(0,0%,100%,.08);border-radius:var(--radius);padding:24px;box-shadow:var(--shadow)}.btn{display:inline-block;border:0;border-radius:10px;padding:10px 16px;font-weight:600;cursor:pointer;background:var(--brand);color:#fff;transition:background .2s ease}.btn:hover{background:#2563eb}.input{width:100%;padding:10px 12px;border-radius:8px;border:1px solid hsla(0,0%,100%,.15);background:hsla(0,0%,100%,.06);color:var(--text);margin-bottom:12px}.input:focus{outline:none;border-color:var(--brand)}.msg{margin-top:12px;font-size:.9rem}.msg.error{color:var(--danger)}.msg.ok{color:var(--ok)}