JSFiddle - React, Tailwind, and code Playground

HTML

<ul class="menu">
        <li><a href="#">fond</a></li>
        <li><a href="#">blago</a></li>
        <li><a href="#">knigi</a></li>
</ul>

CSS

ul {}

ul li {
    float: left;
    margin-left: 1px;
}

ul li a {
    display: block;
    margin: 20px 0 0 0;    
    width: 80px;
    text-align: center;
    height: 30px;
    line-height: 30px;
    color: #000;
    background: #6495ED;
    font-size: 19px;
    text-decoration: none;
    -webkit-border-radius: 10px 10px 0 0;
    -moz-border-radius: 10px 10px 0 0;
    border-radius: 10px 10px 0 0;
    -webkit-transition: color .5s ease;
    -o-transition: color .5s ease;
    -ms-transition: color .5s ease;
    -moz-transition: color .5s ease;    
}
ul li a:hover {
    height: 50px;
    line-height: 50px;
    background: #000080;
    color: red;
    font-weight: bold;
    margin: 0;
}