lass="hljs-keyword">warn</span> <span class="hljs-string">"grid-max-width: #{$grid-max-width} is not a number"</span>;</span>
    $valid<span class="hljs-value">: false;</span>
  }
  <span class="hljs-at_rule">@<span class="hljs-keyword">if</span><span class="hljs-preprocessor"> type-of</span>($grid-columns) != <span class="hljs-string">"number"</span> {</span>
    <span class="hljs-at_rule">@<span class="hljs-keyword">warn</span> <span class="hljs-string">"grid-columns: #{$grid-columns} is not a number"</s