JSFiddle - React, Tailwind, and code Playground

HTML

<div id="block_header">
      Block Text
</div><!--block_header id ends here-->

CSS

#block_header{
    float:left;
    border: 1px solid #333;
    width:300px;
    height:100px;
    text-align:center;
    font-size:18px;
    color:#ccc;
    line-height: 100px;
}