JSFiddle - React, Tailwind, and code Playground

HTML

<button>
    Registrieren
</button>

CSS

button {
  color:hsl(20,50%,40%);
    padding:0.5em;
    background-color:white;
    background-image: linear-gradient(hsl(0,0%,95%), hsl(0,0%,90%));
    border-radius:0.5em;
    border: 1px solid hsl(0,0%,88%);
    text-shadow: white 1px 1px;
	width:9em;
}

button::before {
    content: url(http://fs1.directupload.net/images/150221/4wlu6kbs.png);
	vertical-align: sub;
	margin-right: 7px;
}