JSFiddle - React, Tailwind, and code Playground

HTML

<div id="header">
      <ul id="menu">
        <li>Control Panel</li>
        <li>Settings</li>
      </ul> 
  </div>

CSS

#header {
        width: 100%;
}
#header #menu li{
        list-style: none;
        display: block;
        height: 30px;
        margin:0;
        padding:8px 0px 0px 30px;
        color: #fff;  
        background: #000;
}
#header #menu li+li { 
        color: #d20f0f; 
         background: #dadada;
}