JSFiddle - React, Tailwind, and code Playground

HTML

<div id="buttonBar">
    <div class="buttonWrapper">
        <button>My Button</button>
    </div>
    <div class="buttonWrapper" style="left:33%;" >
        <button>My Button</button>
    </div>
    <div class="buttonWrapper" style="left:66%">
        <button>My Button</button>
    </div>
</div>

CSS

*{
  position:absolute;
}
div#buttonBar{
 width: 300px;
 height: 35px;
 background: #933;
}
div.buttonWrapper{
  width: 33%;
  height: 35px;
  border: 1px solid #333;
}

button{
  width: 100%;
  height: 100%;
  border: none;
}