JSFiddle - React, Tailwind, and code Playground
HTML
<div class="outer"><div class="inner"></div></div>
CSS
div.outer {
width: 5px;
height: 300px;
background: transparent;
position: relative;
}
.inner {
position: absolute;
left:0;
top:auto;
right:0;
bottom: 0;
background: green;
animation: mymove 3s;
animation-fill-mode: both;
}
@-webkit-keyframes mymove {
from {height: 0;}
to {height: 100%;}
}
@keyframes mymove {
from {height: 0;}
to {height: 100%;}
}