JSFiddle - React, Tailwind, and code Playground

HTML

<a href="#" class="big">Ссылка</a>

CSS

a
{
    display: inline-block;
}

a:not(:hover):first-letter
{
    color: blue !important;
    font-size: 100%; 
}

a:first-letter
{
    color: red !important;
    font-size:200%;
}