title: SCSS: multiple box-shadow declaration in mixin
body: <p>I have a following mixin for box-shadow:</p>
  
  <pre><code>@mixin box-shadow($horizontal, $vertical, $blur, $spread, $r, $g, $b, $a, $inset:"") {
      -webkit-box-shadow: $horizontal $vertical $blur $spread rgba($r, $g, $b, $a) unquote($inset);
      box-shadow: $horizontal $vertical $blur $spread rgba($r, $g, $b, $a) unquote($inset);
  }
  </code></pre>
  
  <p>It works fine if I use it like this, for example:</p>
  
  <pre><code>@include box-shadow(0px, 2px, 4px, 0px, 0, 0, 0, 0.4)
  </code></pre>
  
  <p>But how can I chain 2 shadows?</p>
  
  <p>Eventually I want to have a CSS like that, for example:</p>
  
  <pre><code>-webkit-box-shadow: 0px 2px 4px 0px rgba(0, 0, 0, 0.4), 0px 0px 6px 2px rgba(255,255,255,0.5) inset;
  </code></pre>
  
  <p>I tried it with the following code:</p>
  
  <pre><code>@include box-shadow(0px, 2px, 4px, 0px, 0, 0, 0, 0.4), box-shadow(0px, 0px, 6px, 2px, 255, 255, 255, 0.5, inset);
  </code></pre>
  
  <p>But that didn't work. So, is it possible?</p>