calc() in css3

by zoho

HTML

<div id="left">Hello</div>
<div id="middle"></div>
<div id="right">World!</div>

CSS

html, body {
  height: 100%;   
}

#left, #right {
  width: -moz-calc(50% - 20px);
  width: -webkit-calc(50% - 20px);
  width: calc(50% - 20px);
  float: left;
  background-color: #FEE;
  height: 100%;
}

#middle {
  width: 40px;
  float: left;
  background-color: gray;
  height: 100%;
}