title: Using ngx-print, the background is always print in white
body: <p>Actualy i'm using <a href="https://www.npmjs.com/package/ngx-print" rel="nofollow noreferrer">ngx-print</a> npm library to print my <code>div</code> , it works fine , the only problem is that it's not displaying the background color as in the real one:</p>
  <p><a href="https://i.stack.imgur.com/Yq0aZ.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/Yq0aZ.jpg" alt="enter image description here" /></a></p>
  <p><strong>My HTML Code :</strong></p>
  <pre><code>&lt;div class=&quot;hover-div&quot;&gt;
      &lt;button mat-button class=&quot;title-div&quot; printSectionId=&quot;card-container&quot; 
           printTitle=&quot;professionalcard&quot; [useExistingCss]=&quot;true&quot; ngxPrint&gt;
              &lt;div fxLayout=&quot;row&quot;&gt;
                  &lt;mat-icon class=&quot;preview-icon&quot;&gt;print&lt;/mat-icon&gt;
                  &lt;div&gt;print&lt;/div&gt;
              &lt;/div&gt;
       &lt;/button&gt;
  &lt;/div&gt;
  </code></pre>
  <p>has anyone encountered this problem before ? , if yes what is the solution , Thanks.</p>
  <p><strong>Note:</strong> i tried also to print the <code>div</code> without using the library , using <code>window.print()</code> , and i have always the same problem.</p>