JSFiddle - React, Tailwind, and code Playground
by Mehmet Demiray
HTML
<div id="menu-container">
<div class="menu1">
<span>
A<br>A
</span>
</div>
<div class="menu2">
<span>
B<br>B
</span>
</div>
<div class="menu3">
<span>
C<br>C
</span>
</div>
</div>
CSS
#menu-container div{
height: 30px;
width: 30px;
border:1px solid #999;
background: rgba(0,0,0,0.4);
color:#ccc;
left: 0;
text-align: center;
overflow: hidden;
margin: 5px;
-webkit-border-radius: 15px;
-moz-border-radius: 15px;
border-radius: 15px;
}
#menu-container div span{
display: block;
line-height: 27px;
font-size: 16px;
-webkit-transition: all 0.3s ease-in-out;
-moz-transition: all 0.3s ease-in-out;
-o-transition: all 0.3s ease-in-out;
transition: all 0.3s ease-in-out;
}
#menu-container div:hover span{
color: #fff;
background: #FF0000;
height: 300px;
margin: -27px 0 5px 0;
padding: -5px 0 0 0;
}