JSFiddle - React, Tailwind, and code Playground

HTML

<div style="width:100%">
    <div id="cssmenu">
    <ul style="margin-top:0px;">
    <li><a href='#'><span>DASHBOARD</span></a></li>
    <li><a href='#'><span>RESOURCES</span></a></li>
    <li><a href='#'><span>CALL ROUTING</span></a></li>
    <li><a href='#'><span>RECORDINGS & CALL LOGS</span></a></li>
    <li><a href='#'><span>ddddddddd & CALL LOGS</span></a></li>
    </ul>
    </div>
    <div id="header_content">
    <label>Dashboard</label>
    </div>
    <div id="mm_content">
    <label>ffff</label>
    </div>

CSS

#cssmenu{
    margin-top:1px;
    display:inline-block;
} 
#cssmenu > ul li {
    background-color: #F4F4F4;
    display: block;
    position: relative;
    text-decoration:none;}
    #cssmenu > ul li a {
        background-color: #F4F4F4;
        display: block;
        position: relative;
        margin: 0; 
    border-bottom: 1px dotted #d9d9d9;
    border-left: 1px dotted #D9D9D9;
    border-right: 1px dotted #D9D9D9;
    padding: 15px 10px;
    width: 150px;font-size: 11px;
    text-decoration:none;color:#7C7C7C;
}
    #cssmenu > ul li a:hover {
    background-color:#4285F4;
    color:white;
}
    #header_content{
        height:75px;
    width:60%;
    color:White;
    background-color:green;
    display:inline-block;
     vertical-align:top;
}
    #mm_content{
        height:75px;
    width:60%;
    color:White;
    background-color:red;
    display:inline-block;
     vertical-align:top;
}