I want to create two div elements, the left side has a fixed width(ex: 200px) and the right side has a dynamic width(ex: 100%).
I have created, but does not work as required.
HTML
<div id="header">Header</div>
<div id="container">
    <div id="left">Left</div>
    <div id="right">Right</div>
</div>
CSS
div#header {
    height:70px;
    border:1px solid;
}
div#left {
    width:200px;
    height:500px;
    float:left;
    border:1px solid red;
}
div#right {
    width:100%;
    height:500px;
    float:right;
    border:1px solid green;
}
Also you can see the demo on JSFiddle