JSFiddle - React, Tailwind, and code Playground

HTML

<span title="This is my title">Span</span>

CSS

span:hover {
    color: red;
    position: relative;
}

span[title]:hover:after {
    content: attr(title);
    padding: 4px 8px;
    color: #333;
    position: absolute;
    left: 0;
    top: 100%;
    white-space: nowrap;
    z-index: 20px;
    -moz-border-radius: 5px;
    -webkit-border-radius: 5px;
    border-radius: 5px;
    -moz-box-shadow: 0px 0px 4px #222;
    -webkit-box-shadow: 0px 0px 4px #222;
    box-shadow: 0px 0px 4px #222;
    background-image: -moz-linear-gradient(top, #eeeeee, #cccccc);
    background-image: -webkit-gradient(linear,left top,left bottom,color-stop(0, #eeeeee),color-stop(1, #cccccc));
    background-image: -webkit-linear-gradient(top, #eeeeee, #cccccc);
    background-image: -moz-linear-gradient(top, #eeeeee, #cccccc);
    background-image: -ms-linear-gradient(top, #eeeeee, #cccccc);
    background-image: -o-linear-gradient(top, #eeeeee, #cccccc);
}