title: background image in bootstrap 4 column
body: <p>On my page:</p>
  
  <pre><code>&lt;div id="cont" class="container-fluid"&gt;
      &lt;div class="row"&gt;
          &lt;div id="sidebarcont" class="col-sm-3"&gt;
              &lt;div id="sidebar"  class="position-fixed"&gt;
              &lt;/div&gt;
          &lt;/div&gt;
          &lt;div id="main" class="col-sm-9"&gt;
              &lt;div id="first_row"&gt;   
              &lt;/div&gt;
              &lt;div id="second_row"&gt;
              &lt;/div&gt;
              &lt;div id="first_row"&gt;
              &lt;/div&gt;
              &lt;div id="second_row"&gt;
              &lt;/div&gt;
          &lt;/div&gt;
      &lt;/div&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>And CSS:</p>
  
  <pre><code>#sidebar {
        background-image: url('../Media/cos.png'),url('../Media/ant.jpg');
        background-repeat: repeat, no-repeat;
        background-size:contain;
        background-position:top;
        height:auto;
        }
  #sidebarcont {
        width:100%;
        }
  </code></pre>
  
  <p>I would like the background image to be placed on top of the sidebar, fill the whole width of it (<code>background-size: contain</code>) and be fixed. What I have achieved is the sidebar is placed at the top but it is a size: <code>70px/30px</code></p>