body { font-family: Arial, sans-serif; background:#eef1f6; }
.login-box {
  width:360px; margin:120px auto; background:#fff;
  padding:25px; border-radius:8px;
  box-shadow:0 4px 12px rgba(0,0,0,.15);
}
input, button {
  width:100%; padding:10px; margin-top:10px;
}
button {
  background:#4f46e5; color:#fff; border:0;
  border-radius:4px; cursor:pointer;
}
.error { color:red; }