Edit in JSFiddle

body {
    margin: 30px
    }

.deneme {
    width: 50px;
    height: 50px;
    background-color: #06F;
    color: #fff;
    -moz-transform: skew(10deg, 20deg);
    -ms-transform: skew(10deg, 20deg);
    -o-transform: skew(10deg, 20deg);
    -webkit-transform: skew(10deg, 20deg);
    transform: skew(10deg, 20deg)
    }
<div class="deneme">
</div>