JSFiddle - React, Tailwind, and code Playground

HTML

<div class="fundo_main">
    <div class="fundo"></div>
</div>

CSS

.fundo_main {
    width:200px;
    height:200px;
    background-color:red;
    position:relative;
}
.fundo_main:hover {
    width:200px;
    height:200px;
    -webkit-animation-name:myfirst;
    position:relative;
}
.fundo {
    width:200px;
    height:200px;
    background-color:red;
    position:relative;
    -webkit-animation-name:myfirst;
}

.fundo_main:hover .fundo {
    width:200px;
    height:200px;
    background-color:blue;
    -webkit-animation-name:myfirst;
    -webkit-animation-duration:.3s;
    -webkit-animation-timing-function:linear;
    -webkit-animation-direction:left;

}
@-webkit-keyframes myfirst {
    0% { width:0px; }
    65% { width: 150px;}    
    100% { width:200px; }
}