SO - 18099211

by Arun P Johny

HTML

<div class="mainDiv">mainDiv</div>

CSS

.mainDiv{
    height:100px !important
}
.mainDiv{
    border: 1px solid blue;
}

JavaScript

$(".mainDiv").css({
    "min-height" : ($(window).height() * 0.7) +"px"
});