JSFiddle - React, Tailwind, and code Playground

HTML

<div class="elliptical-container">
     <h1>Content</h1>
 </div>

CSS

html, body {
    margin: 0;
    height: 100%;
    background-color: #3B2053;
}

h1 {
    opacity: 0.2;
    text-align: center;
}

.elliptical-container {
    margin-top: 100px;
    box-sizing: border-box;
    height: 100%;
    background: #EEEDEE;
    border-top-left-radius: 50% 75px;
    border-top-right-radius: 50% 75px;
    box-shadow: 0 0 0 4px #EEEDEE;
    border-top: 1px dashed #3B2053;
}