div#s2-events > div {
    display: inline-block;
    width: 30%;
    margin-right: 5%;
    float:left;
    background-color:#f7f7f7;
    border:2px solid black;
    padding:20px;
}

div#s2-events > div:nth-child(3n){
    margin-right:0;
}

@media(max-width:980px){
    div#s2-events > div{
        width:100%;
    }
}