<div class="glass">
<span class="liquid"></span>
</div>
.glass {
height: 260px;
width: 150px;
position: relative;
background-image: url('http://i.imgur.com/17f4WYs.png');
background-repeat: no-repeat;
}
.liquid {
z-index:-1;
position:absolute;
bottom:0;
width: 140px;
height: 80%;
background-image: -webkit-linear-gradient(bottom, rgb(255, 136, 0), rgb(255, 203, 0))
}