JSFiddle - React, Tailwind, and code Playground

HTML

<div class="mancha">
    <div class="logo"></div>    
    <div id="content-area" class="espacio">
             <div class="eltitular">HEADER</div>
             <div class="lacarta">LEFT CONTENT</div>
             <div id="sidebar">RIGHT CONTENT</div>
        </div>
</div>

CSS

div {
    border: 1px solid red
}
.espacio{
    margin-left: 192px;
    background: transparent;
    width:808px !important
}
.lacarta{
        width:590px;
        float:left;
}
#sidebar{
        width:210px;
        float:right
}