JSFiddle - React, Tailwind, and code Playground

http://stackoverflow.com/questions/4676442/two-floated-columns-one-fixed-one-loose-width http://coding.smashingmagazine.com/2009/07/27/the-definitive-guide-to-using-negative-margins/

HTML

<div class="container">
    <div class="left">left</div>
    <div class="right">right</div>
</div>

CSS

html, body, .container {
    height:100%;
    padding:0;
    margin:0;
}
.container {
    min-width: 300px;
    border:5px solid red;
}
.left {
    float:left;
    width: 185px;
    margin-right: -185px;
    height:100%;
    border:5px solid green;
}
.right {
    margin-left:185px;
    border:5px solid blue;
}
.container, .left, .right {
    box-sizing: border-box;
    -moz-box-sizing: border-box;
    -webkit-box-sizing: border-box;
    /* or use border:0; instead */
    overflow:auto;
}