.main_content{
    height: 100vh;
    width: 100%;
    display: table;
}
.sub_content{
    text-align: center;
    height: auto;
    margin: auto;
    display: table-cell;
    vertical-align: middle;
}
.sub_content p{
    margin-top: 3em;
    font-size: 1.5em;
}
.sub_content a{
    font-size: 1.6em;
    font-weight: bold;
}