Code
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>Document</title>
<link href="https://unpkg.com/[email protected]^1.0/dist/tailwind.min.css" rel="stylesheet">
<script src="https://cdn.jsdelivr.net/gh/alpinejs/[email protected]/dist/alpine.min.js" defer></script>
<link href="https://fonts.googleapis.com/css?family=Source+Code+Pro|Roboto&display=swap" rel="stylesheet">
</head>
<style>
.bg-border-radius {
margin: -40vw auto 0;
width: 100%;
height: 70vw;
overflow: hidden;
border-radius: 0 0 70% 70%;
background-color: #0080C1;
}
</style>
<body style="font-family:Roboto">
<div class="bg-border-radius"></div>
</body>
</html>