body{
    background: linear-gradient(135deg, #6dd5fa, #2980b9);
    background-size: cover;
    background-position: center;
    min-height:100vh;
    display:flex;
    justify-content:center;
            align-items:center;
        }
        .card{ border-radius:12px;}
        .icono{font-size:55px;}
        .titulo-error{
            border-bottom: 2px solid #000;
            display: inline-block;
            padding-bottom: 5px;
        }