CSS | Flexbox Layout
The flexible boxes, or flexbox, is a new layout mode in CSS3.
HTML
<div class="flex">
<div></div>
<div></div>
<div></div>
</div>
CSS
.flex{
width: 100%;
height: 200px;
border: 1px solid #ddd;
font: 14px Arial;
display: flex;
display: -webkit-flex;
flex-direction: row;
-webkit-flex-direction: row;
flex-wrap:wrap;
}
.flex > div{
width: 30px;
flex: 1 1 auto;
-webkit-flex: 1 1 auto;
transition: width 0.7s ease-out;
-webkit-transition: width 0.7s ease-out;
}
.flex > div:nth-child(1){ background : #007AA2; }
.flex > div:nth-child(2){ background : #FFF; }
.flex > div:nth-child(3){ background : #7FCADE; }
.flex > div:hover{
width: 20%;
}