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Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.



Functionning is simple:
	1. the DIV and DIV::BEFORE are two superposed half circles.
	2. the DIV is red, and the ::BEFORE is white.
	3. the ::BEFORE is right-above the DIV and it is the one that is rotated with CSS-transforms.

	* you can easily visualize what is going on here by removing the div{overflow:hidden} and changing the background-color of the DIV::BEFORE.
	* the outer circular border can be removed by removing the "border" on the DIV. However, there is still some color remaining. It’s CSS behaviour that I can’t totally control. Might I suggest you deal with it and/or take advantage of it or find some trick. I didn’t found.

  * Both elements are half-circles. They are twice as wide than they are tall.
	* The border-radius on the DIV is equal to height on top-left and top-right corners.


<p>For a JS-enhanced still very lightweight version of this CSS-angle, try <a href="https://codepen.io/lehollandaisvolant/pen/NLKGpO" target="_blank">this other PEN</a></p>
              div {

div {
    height: 300px;
    width: 600px;
    overflow: hidden;
    position: relative;
    background: crimson;
    border-radius: 300px 300px 0 0;
    border: 1px solid crimson;
div::before {
    height: inherit;
    width: inherit;
    position: absolute;
    content: "";
    background-color: white;
    transform-origin: 50% 100%;
    transform: rotate(var(--angle));
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