title: Show icon with the after pseudo selector
body: <p>I want to show a icon in css. But until now the icon is not visible. 
  Only when I define some text in the a href attribute then the icon will be visible, but also the text</p>
  
  <p>Googled, following tutorials</p>
  
  <p>So I hava a href selector, like this:</p>
  
  <pre><code>return $"&lt;a href = \"{baseUrl}api/Devices/GetDownload/{model.AttachmentKey}/\" class=\"msgdownload\"&gt;&lt;/a&gt;";
  
  </code></pre>
  
  <p>and the css class:</p>
  
  <pre><code>.msgdownload {
  
    position: relative;
  
  }
  
  .msgdownload::after {
    content:'';
    position: absolute;
    top: 0;
    right: 0;
    width: 100%;
    height: 100% ;
    background: url('../hepchat/downlaod\ -\ kopie.jpg') no-repeat bottom;
  }
  </code></pre>
  
  <p>But the image is not vissible now.</p>
  
  <p>But for example if I do this:</p>
  
  <pre><code>return $"&lt;a href = \"{baseUrl}api/Devices/GetDownload/{model.AttachmentKey}/\" class=\"msgdownload\"&gt;donwload&lt;/a&gt;";
  
  </code></pre>
  
  <p>Then the image is vissible. But also the text download.But I only want to show the Image not the text.</p>
  
  <p>Thank you.</p>
  
  <p>So I try to make it empty like this:</p>
  
  <pre><code>return $"&lt;a href = \"{baseUrl}api/Devices/GetDownload/{model.AttachmentKey}/\" class=\"msgdownload\"&gt;&lt;/a&gt;";
  </code></pre>