Fixes #10505: Document more of LESS vars and mixins

_includes/nav-css.html

@@ -105,3 +105,11 @@
     <li><a href="#responsive-utilities-tests">Test cases</a></li>
   </ul>
 </li>
+<li>
+  <a href="#less">Using LESS</a>
+  <ul class="nav">
+    <li><a href="#less-variables">Variables</a></li>
+    <li><a href="#less-mixins-vendor">Vendor mixins</a></li>
+    <li><a href="#less-mixins-utility">Utility mixins</a></li>
+  </ul>
+</li>

docs-assets/css/docs.css

@@ -597,6 +597,35 @@ h1[id] {
 }
 
 
+/*
+ * Color swatches
+ *
+ * Color swatches and associated values for our grayscale and brand colors.
+ */
+
+.color-swatches {
+  margin: 0 -5px;
+  overflow: hidden; /* clearfix */
+}
+.color-swatch {
+  float: left;
+  width:  100px;
+  height: 100px;
+  margin: 0 5px;
+  border-radius: 3px;
+}
+.color-swatches .gray-darker   { background-color: #222; }
+.color-swatches .gray-dark     { background-color: #333; }
+.color-swatches .gray          { background-color: #555; }
+.color-swatches .gray-light    { background-color: #999; }
+.color-swatches .gray-lighter  { background-color: #eee; }
+.color-swatches .brand-primary { background-color: #428bca; }
+.color-swatches .brand-success { background-color: #5cb85c; }
+.color-swatches .brand-warning { background-color: #f0ad4e; }
+.color-swatches .brand-danger  { background-color: #d9534f; }
+.color-swatches .brand-info    { background-color: #5bc0de; }
+
+
 /*
  * Team members
  *