html, body {
    height: 100%;
    margin: 0;
    display: flex;
    flex-direction: column;
}

main {
    font-family: Arial, Helvetica, sans-serif;
    font-size: 1.2em;
    text-align: center;
    flex: 1;
}

footer {
    background-color: #8c8c8c;
    color: white;
    text-align: center;
    padding: 40px 0;
    font-size: 16px;
    width: 100%;
}

table{
    margin: auto;
}

td{
    padding: 20px;
}

.messaggio{
    width: 50%;
    margin: 40px auto;
    text-align: justify;
}

.form-table th, .data-table th{
    text-align: right;
}

.form-table td, .data-table td{
    text-align: left;
}

.btn{
    margin: 40px;
    width: 50%;
    height: 70px;
    font-size: 1.4em;
    font-weight: bold;
    background: lightgray;
    border: 2px solid darkgray;
    border-radius: 15px;
}

.btn-submit{
    background: lightgreen;
    border: 2px solid darkgreen;
}

.error{
    margin: 20px;
    color: red;
    font-size: 24px;
}