body {
    background-color: white;
}

.imgButton{
    text-align:center;
}


.my-col {
    float: left;
    width: 30%;
    margin-left: 5px;
    margin-right: 5px;
}

@media only screen and (max-width: 768px) {
    .my-col {
        width: 45%;
        margin-left: 5px;
        margin-right: 5px;
    }
}

@media only screen and (max-width: 620px) {
    .my-col {
        width: 100%;
        margin-left: 0px;
        margin-right: 0px;
    }
}


.responsive {
    width: 100%;
    height: auto;
    display: block;
    margin-bottom: 20px;
}