body { margin: 0; min-height: 100vh; display: grid; place-items: center; background: #f4f6fa; color: #111827; font: 16px system-ui, sans-serif; }
main { width: min(400px, calc(100vw - 64px)); padding: 24px; background: white; border-radius: 16px; box-shadow: 0 8px 32px #0001; }
h1 { font-size: 24px; }
p { line-height: 1.5; color: #64748b; }
form { display: grid; gap: 12px; }
input, button { box-sizing: border-box; width: 100%; padding: 12px; border: 1px solid #cbd5e1; border-radius: 8px; font: inherit; }
button { background: #2563eb; color: white; cursor: pointer; }
.error { color: #b91c1c; }