title: Pass argument to keyframes animation
body: <p>So I saw this question (<a href="https://stackoverflow.com/questions/33033541/add-argument-into-keyframes-property-less">Add argument into @keyframes property Less</a>) however it doesn't completely solve my problem.</p>
  
  <pre><code>.progress-anim(@percentage: 0%) {
      @-webkit-keyframes progress { 
          to { width: @percentage }
      }
  
      @-moz-keyframes progress { 
          to { width: @percentage }
      }
  
      @-ms-keyframes progress { 
          to { width: @percentage }
      }
  
      @keyframes progress { 
          to { width: @percentage }
      }
  }
  </code></pre>
  
  <p>Above is what I'm trying to do. This, I understand. What I don't understand, is how to run it from a <code>animation</code> property.</p>
  
  <pre><code>.progress {
      -webkit-animation: ? 2s 1 forwards;
      -moz-animation: ? 2s 1 forwards;
      -ms-animation: ? 2s 1 forwards;
      animation: ? 2s 1 forwards;
  }
  </code></pre>
  
  <p>What do I put in place for the <code>?</code>? I don't understand this.</p>
  
  <p>Do I put the <code>animation</code> calls within <code>.progress-anim</code>?</p>