JSFiddle - React, Tailwind, and code Playground

HTML

<div id="your_div">
    <svg id="back" viewBox="0 0 100 10" preserveAspectRatio="none">
        <path d="M 0,0 L 100,0 100,10 0,10 0,0 M 50,8 L 55,6 52,6 52,2 48,2 48,6 45,6 z" style="fill: white; fill-rule: evenodd;"></path>
    </svg>
</div>

CSS

body {
    background-image: url(http://i.imgur.com/XxGffrU.jpg);
    background-size: cover;
    background-position: center bottom;
    min-height: 1000px;
    margin: 0;
}

#your_div {
    position: fixed;
    top: 30%;
    width: 90%;
    left: 5%;
    height: 100px;
}

#back {
    width: 100%;
    height: 100%;
}