JSFiddle - React, Tailwind, and code Playground

HTML

<div id="maincontainer">
    <div id="leftcolumn"></div>
 
    <div id="contentwrapper"></div>
</div>

CSS

#maincontainer {
    width:100%;
    height: 100%;
}
#leftcolumn {
    display:inline-block;
    width: 100px;
    height: 100%;
    background: blue;
}
#contentwrapper {
    display:inline-block;
    width:100%;
    height: 100%;
    background-color: red;
}