JSFiddle - React, Tailwind, and code Playground

HTML

<ul class="hMenu">
        <li onmouseover="showMenu(this);" onmouseout="hideMenu(this);"><a style="color: red;" href="javascript:void(0);">prod</a>           
            <br />
            <div class="arrow_box">             
                <div class="lay1">
                    <div>
                        <a href="" class="topMenu">Manage Content</a><br>
                        <a href="" class="secondMenu">&nbsp;&nbsp;&nbsp;&nbsp;Message </a>
                    </div>
                    <br />
                    <br />
                    <div>
                        <a href="" class="topMenu">Manage Assignment</a><br>
                        <a href="" class="secondMenu">&nbsp;&nbsp;&nbsp;&nbsp;User Inquiry</a></div>
                </div>
            </div>
        </li>
        <li onmouseover="showMenu(this);" onmouseout="hideMenu(this);"><a style="color: red;"  href="javascript:void(0);">prod2</a>            
            <br />
            <div class="arrow_box">
            <br />
                <div class="lay1">
                    <div>
                        <a href="" class="topMenu">Manage Content</a><br>
                        <a href="" class="secondMenu">&nbsp;&nbsp;&nbsp;&nbsp;Message </a>
                        <br>
                        <a href="" class="secondMenu">&nbsp;&nbsp;&nbsp;&nbsp;Help </a>
                    </div>
                    <br />
                    <br />
                    <div>
                        <a href="" class="topMenu">Manage Assignment</a><br>
                        <a href="" class="secondMenu">&nbsp;&nbsp;&nbsp;&nbsp;User Inquiry</a></div>
                </div>
            </div>
        </li>
    </ul>

CSS

ul.hMenu  { 
            margin: 0;
            padding: 0; 
            z-index: 1;                 
        }
        ul.hMenu > li  {  
            margin: 0;
            padding: 0;
            list-style: none;
            float: left;
            width:140px;
        }
        ul.hMenu li a { 
            display: block; 
            text-align: left;
            text-decoration: none
        }          
        ul.hMenu li > div  {                    
            position: absolute;             
            display: none;                
        }
        ul.hMenu div a {background: yellow;     
        }           

        div.lay1{ float:left;}  
        div.lay1 br{line-height:50%}
        .topMenu{font:bold 12px arial;color:#169e39;text-decoration: none;}
        .secondMenu{font:12px arial;color:#000000;text-decoration: none;}
        .arrow_box {
            position: relative;
            background: red;
            border: 4px solid #c2e1f5;
        }
        .arrow_box:after, .arrow_box:before {
            bottom: 100%;
            border: solid transparent;
            content: " ";
            height: 0;
            width: 0;
            position: absolute;
            pointer-events: none;
        }
        .arrow_box:after {
            border-color: rgba(149, 213, 53, 0);
            border-bottom-color: red;
            border-width: 13px;
            left: 10%;
            margin-left: -13px;
        }
        .arrow_box:before {
            border-color: rgba(194, 225, 245, 0);
            border-bottom-color: #c2e1f5;
            border-width: 19px;
            left: 10%;
            margin-left: -19px;
        }

JavaScript

function showMenu(obj){ 
            var a=obj.children[0];
            a.style.color="blue";
            var div = obj.children[2];
            obj.style.backgroundColor="yellow";
            div.style.display="block";
        }

function hideMenu(obj){
            var a=obj.children[0];
            a.style.color="red";
            var div = obj.children[2];          
            div.style.display="none";
            obj.style.backgroundColor="";
        }