title: Slidify - how to customize a slide background?
body: <p>I have been struggling to customize the background of my slide deck using the 'slidify' package.</p>
  
  <p>Actually, I could do it for the title slide by modifying the file 'slidify.css' though:</p>
  
  <pre><code>.title-slide {
  /*background-color: #CBE7A5 */; /* #EDE0CF; ; #CA9F9D*/
  background-image:url(C:/path/mypng.png);
  background-repeat: no-repeat;
  background-position: center center;
  background-size: cover;
   }
  </code></pre>
  
  <p>However I can't find how to do it for the 'standard' slides. 
  I can use </p>
  
  <pre><code>--- bg:url(C:/path/mypng.png)  
  </code></pre>
  
  <p>directly in my .Rmd file but I am unable to add the repeat and size options.</p>
  
  <p>Does anyone have any tips on how to do it / where to add it within the CSS files?</p>
  
  <p>Cheers,</p>