:root { color-scheme: dark; }
* { box-sizing: border-box; }
body { margin: 0; min-height: 100vh; display: flex; align-items: center; justify-content: center; background: #0B1220; color: #E6EAF2; font: 16px/1.4 system-ui, -apple-system, 'Segoe UI', sans-serif; padding: 16px; }
.box { width: 100%; max-width: 360px; background: #121A2B; border: 1px solid #1F2A40; border-radius: 18px; padding: 28px 22px; }
.brand { font-size: 26px; font-weight: 700; letter-spacing: .14em; }
.sub { margin: 4px 0 22px; color: #8D99B3; font-size: 14px; }
label { display: block; font-size: 13px; color: #C9D1E1; margin-bottom: 6px; }
input { width: 100%; min-height: 48px; border-radius: 12px; border: 1px solid #2A3753; background: #0B1220; color: #E6EAF2; font-size: 16px; padding: 0 14px; }
input:focus { outline: 2px solid #5CC8FF; outline-offset: 1px; }
.err { min-height: 20px; margin: 8px 0; color: #FF8A6B; font-size: 13px; }
button { width: 100%; min-height: 48px; border: 0; border-radius: 12px; background: #5CC8FF; color: #0B1220; font-size: 16px; font-weight: 600; cursor: pointer; }