title: CSS flex-wrap how to make the height do not stretch
body: <p>There are big gaps between <code>box3, box1</code> and <code>box4, box6</code> How to get rid of the gap? so each <code>box</code> could have the dynamic height? </p>
  
  <p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
  <div class="snippet-code">
  <pre class="snippet-code-css lang-css prettyprint-override"><code>.wrap {
    display: flex;
    align-items: baseline;
    align-content:flex-start;
    justify-content: space-between;
    flex-wrap: wrap; 
    background-color: lightblue;
  }
  
  .box {
    display: flex;
    background-color: tomato;
    box-sizing: border-box;
    border: 1px solid #C4C4C4;
    height: 100px;
    width: 45%;
    margin-top: 15px;
  }
  
  .box1, .box4 {
    height: 20px;
  }</code></pre>
  <pre class="snippet-code-html lang-html prettyprint-override"><code>  &lt;div class="wrap"&gt;
      &lt;div class="box box1"&gt;box1&lt;/div&gt;
      &lt;div class="box box2"&gt;box2&lt;/div&gt;
      &lt;div class="box box3"&gt;box3&lt;/div&gt;
      &lt;div class="box box4"&gt;box4&lt;/div&gt;
      &lt;div class="box box5"&gt;box5&lt;/div&gt;
      &lt;div class="box box6"&gt;box6&lt;/div&gt;
    &lt;/div&gt;</code></pre>
  </div>
  </div>
  </p>
  
  <p>Here is the desired layout. Thanks</p>
  
  <p><a href="https://i.stack.imgur.com/0Fbie.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/0Fbie.png" alt="enter image description here"></a></p>