JSFiddle - React, Tailwind, and code Playground

HTML

<div class="div-box">
    <div class="text-div"><i>Всплывающий по наведению текст

CSS

.div-box {
    width: 40px;
    height: 20px;
    border: 1px dashed #ccc;
    cursor: pointer;
}

.text-div {
    bottom:2px;
    left:2px;
    display: table;
    padding: 2px 4px;
    transition:all 1s ease;
    position:absolute;
    color:transparent;
}

.div-box:hover .text-div {
    border-radius: 0 10px 0 0 ;
    box-shadow:2px -1px 9px rgba(0,0,0,.3);
    color:#666;
}