title: how to create css concave/convex shapes
body: <p>I want to create two divs with the background white shape depicted below. As you can see it's basically a rectangle and a ellipse-shape being cut out. It should be able to produce a box-shadow.</p>
  
  <p>Is there a way to achieve this with css only?</p>
  
  <p><a href="https://i.stack.imgur.com/MB9wF.png" rel="noreferrer"><img src="https://i.stack.imgur.com/MB9wF.png" alt="Concave shapes"></a></p>