JSFiddle - React, Tailwind, and code Playground

by extranion

HTML

<body>
    <header>
        <div class="contact">
            lorem ipsum
            <div class="wrap-btn">
                <button>inloggen</button>
            </div>
        </div>
    </header>
</body>

CSS

* { 
    margin:0; padding:0; 
}
body { 
    background-image: url("http://gallery.photo.net/photo/8551440-md.jpg");
}
button { 
    background:none; border:none; 
}

header { 
    height:100px; 
    background-color: rgba(41, 52, 61, .8); 
}

.contact { 
    float:right; 
    height:100px; 
    width:200px; 
    position:relative; 
}

.wrap-btn { 
    position:absolute; 
    top:100%; 
    left:50px; 
    height:30px; 
    width:100px; 
    border-radius: 0 0 20px 20px; 
    background-color: rgba(41, 52, 61, .8); 
}
button { 
    position:absolute; 
    bottom:10px; 
    left:10px; 
    width:80px; 
    height:40px; 
    background:orange; 
    border-radius:15px; 
}