JSFiddle - React, Tailwind, and code Playground

by TheoI

HTML

<div class='container'>
    Hover over me
<div class='pointer'></div>
<div class='element'>
</div>
</div>

CSS

.container {
    width: 300px;
    min-height: 100px;
}
.pointer {    
    -webkit-transition: all 1s;
    margin: 0 auto;
    background-color: gray;
    width: 0;
    height: 0px;
    border-top: none;
    border-left: 0px solid white; 
    border-right: 0px solid white; 
    border-bottom: 0px solid transparent;
}
.element {
    -webkit-transition: all 1s;
    width: 100%;
    height: 0;
    background-color: gray;
}
.container:hover .pointer {
    border-width: 10px; 
}
.container:hover .element {
    height: 100px;
}