title: iframe: removing internal (grey) border
body: <p>I want to embed a pdf-document on my website, but cannot manage to display the document in the iframe without an overwhelmingly useless gray border.</p>
  
  <p>Now I see that this gray border is not always displayed when embedding a pdf-document, but in my example as you can see in the picture, there is a large border withing the iframe, next to the pdf-page I actually would like to display.</p>
  
  <p>See here what I am talking about: 
  <img src="https://i.imgur.com/LKkW16d.jpg" alt=""></p>
  
  <p>I am using a simple iframe-tag within a div-tag.</p>
  
  <p>Does anybody know if it is possible to remove the grey border ("Border in iframe") or how I can deal with this problem?</p>