JSFiddle - React, Tailwind, and code Playground

HTML

<div class="outer_div">
    <div class="inner_div">
        <div id="percent_count">
            
        </div>
    </div>
</div>

CSS

.outer_div {
    width: 250px;
    height: 25px;
    background-color: #CCC;
}
.inner_div {
    width: 5px;
    height: 21px;
    position: relative; top: 2px; left: 5px;
    background-color: #81DB92;
    box-shadow: inset 0px 0px 20px #6CC47D;
    -webkit-animation-name: progressBar;
    -webkit-animation-duration: 3s;
    -webkit-animation-fill-mode: forwards;
}
#percent_count {
    font: normal 1em calibri;
    position: relative;
    left: 10px;
}

@-webkit-keyframes progressBar {
    from {
        width: 5px;
    }
    to {
        width: 200px;
    }
}