title: Conditional when in less-file
body: <p>I am making a theme editor for WordPress, and would like to use less to build the CSS file.</p>
  
  <p>I have put a string in a variable like this:</p>
  
  <pre><code>@banner-separation-style: 'thick_border';
  </code></pre>
  
  <p>Then I'm trying to use when() like this:</p>
  
  <pre><code>when (@banner-separation-style = 'thick_border') {
      header {
          ... some style
      }
      ... and some css selectors
  }
  </code></pre>
  
  <p>I've also tried combinations without quoting the variable.</p>
  
  <p>How do I properly create something similar to if-blocks with less?</p>