:root{color-scheme:dark}
*{box-sizing:border-box}
body{margin:0;min-height:100vh;display:grid;place-items:center;
  font:16px/1.5 ui-sans-serif,system-ui,-apple-system,"Segoe UI",Roboto,sans-serif;
  color:#e8eef7;background:radial-gradient(120% 120% at 50% 0%,#1b2740 0%,#0c1120 60%,#080b14 100%)}
.card{width:min(92vw,340px);padding:28px;border-radius:18px;
  background:rgba(20,28,46,.82);border:1px solid rgba(255,255,255,.10);
  box-shadow:0 24px 60px rgba(0,0,0,.45);backdrop-filter:blur(8px)}
h1{margin:0 0 4px;font-size:24px;letter-spacing:.2px}
.sub{margin:0 0 20px;color:#93a3bd;font-size:13px}
label{display:block;margin-bottom:14px;font-size:12px;color:#a9b8d0;letter-spacing:.3px}
input{width:100%;margin-top:6px;padding:11px 12px;border-radius:10px;
  border:1px solid rgba(255,255,255,.14);background:rgba(8,12,22,.75);color:#e8eef7;font-size:15px}
input:focus{outline:none;border-color:#6ea8ff;box-shadow:0 0 0 3px rgba(110,168,255,.18)}
button{width:100%;margin-top:6px;padding:12px;border:0;border-radius:10px;cursor:pointer;
  font-size:15px;font-weight:600;color:#0b1020;background:linear-gradient(180deg,#8fd0ff,#5fa8f5)}
button:hover{filter:brightness(1.06)}
.err{margin:0 0 14px;padding:9px 11px;border-radius:9px;font-size:13px;
  background:rgba(255,107,107,.13);border:1px solid rgba(255,107,107,.35);color:#ffb4b4}