title: Create a curve shape using css?
body: <p>i really need your help..</p>
  
  <p>did anyone know how to make a shape like this using css?</p>
  
  <p><a href="https://i.stack.imgur.com/WAOk0.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/WAOk0.jpg" alt="enter image description here"></a></p>
  
  <p>i tried to make it, but now i stuck..</p>
  
  <p><a href="http://codepen.io/nassermaronie/pen/NxwMjY" rel="nofollow noreferrer">here's my code pen</a></p>
  
  <p>Here's the css style and HTML</p>
  
  <p><div class="snippet" data-lang="js" data-hide="false" data-console="false" data-babel="false">
  <div class="snippet-code">
  <pre class="snippet-code-css lang-css prettyprint-override"><code>.a {
    width: 20%;
    height: 500px;
    background-color: red;
    display: inline-block;
    margin: 0;
  }
  .b {
    display: inline-block;
    position: absolute;
    width: 20%;
    height: 500px;
    background-color: black;
    margin: 0;
    border-radius: 50% 0 0 50%;
    left: 20%;
  }</code></pre>
  <pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;div id="container"&gt;
    &lt;div class="a"&gt;
      ...
    &lt;/div&gt;
    &lt;div class="b"&gt;
      ...
    &lt;/div&gt;
  &lt;/div&gt;</code></pre>
  </div>
  </div>
  </p>