.container {
    text-align:center;
}

.mydiv {
    padding:30px 60px;
    background:#ff2222;
    color:#fff;
    font-size:48pt;
    border-radius:5px;
    display:inline-block;
    
    margin-top:200px;
    transition:1s;
    
}

@media screen and (max-width: 1200px) {
    .mydiv {
    background:#ff9900;
    color:#222;
    }
}

@media screen and (max-width: 1000px) {
    .mydiv {
    background:#0099dd;
    color:#fff;
    transform:rotate(45deg);
    }
}

@media screen and (max-width: 800px) {
    .mydiv {
    background:#80cc10;
    color:#fff;
    transform:rotate(90deg);
    }
}

@media screen and (max-width: 600px) {
    .mydiv {
    background:#bb33aa;
    color:#fff;
    transform:rotate(90deg);
    font-size:32pt;
    }
}