@media screen and (min-width: 600px) {
    .block.block-right {
        width: 30%;
    }
}

@media screen and (min-width: 1200px) {
    .block.block-right {
        width: 30%;
    }
}

@media screen and (min-width: 1500px) {
    .block.block-right {
        width: 30%;
    }
}