body { font-family: Arial; background:#f0f0f0; display:flex; justify-content:center; align-items:center; height:100vh; }
.login-container { background:#fff; padding:2em; border-radius:5px; box-shadow:0 3px 10px rgba(0,0,0,0.2); width:300px; }
input { margin-bottom:1em; padding:0.5em; width:100%; }
button { padding:0.5em; width:100%; background:#61AE52; color:#fff; border:none; border-radius:4px; cursor:pointer; }
button:hover { background:#499B42; }
.error { color:red; margin-bottom:1em; text-align:center; }