body{
	font-family: Arial, sans-serif;
	background-color: #eee;
}

.caja{
	width: 320px;
	margin: 100px auto;
	background-color: white;
	padding: 20px;
	border: 1px solid #ccc;
}

input{
	width: 100%;
	padding: 8px;
	margin: 8px 0;
	box-sizing: border-box;
}

button{
	width: 100%;
	padding: 8px;
	background-color: #4caf50;
	color: white;
	border: none;
}

.error{
	color: red;
}