JSFiddle - React, Tailwind, and code Playground

HTML

<div class="vk">
    
</div>

CSS

body {
    background: #ccc;
}

.vk {
    width: 70px;
    height: 70px;
    border-radius: 35px;
    background-color: #586979;
    background-position: 50% 50%;
	background-repeat: no-repeat;
    transition: all 0.2s ease;
}

.vk:hover {
    background-color: #3AA8BF;
}

.vk {
    background-image: url(http://www.slot.ru/images/i/vk-icon.png);
}