Document .card-*-outline variants

docs/components/card.md

@@ -312,6 +312,61 @@ Cards include their own variant classes for quickly changing the `background-col
 </div>
 {% endexample %}
 
+## Outline variants
+
+In need of a colored card, but not the hefty background colors they bring? Replace the default modifier classes with the `.card-*-outline` ones to style just the `border-color` of a card.
+
+{% example html %}
+<div class="card card-primary-outline text-xs-center">
+  <div class="card-block">
+    <blockquote class="card-blockquote">
+      <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Integer posuere erat a ante.</p>
+      <footer>Someone famous in <cite title="Source Title">Source Title</cite></footer>
+    </blockquote>
+  </div>
+</div>
+<div class="card card-secondary-outline text-xs-center">
+  <div class="card-block">
+    <blockquote class="card-blockquote">
+      <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Integer posuere erat a ante.</p>
+      <footer>Someone famous in <cite title="Source Title">Source Title</cite></footer>
+    </blockquote>
+  </div>
+</div>
+<div class="card card-success-outline text-xs-center">
+  <div class="card-block">
+    <blockquote class="card-blockquote">
+      <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Integer posuere erat a ante.</p>
+      <footer>Someone famous in <cite title="Source Title">Source Title</cite></footer>
+    </blockquote>
+  </div>
+</div>
+<div class="card card-info-outline text-xs-center">
+  <div class="card-block">
+    <blockquote class="card-blockquote">
+      <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Integer posuere erat a ante.</p>
+      <footer>Someone famous in <cite title="Source Title">Source Title</cite></footer>
+    </blockquote>
+  </div>
+</div>
+<div class="card card-warning-outline text-xs-center">
+  <div class="card-block">
+    <blockquote class="card-blockquote">
+      <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Integer posuere erat a ante.</p>
+      <footer>Someone famous in <cite title="Source Title">Source Title</cite></footer>
+    </blockquote>
+  </div>
+</div>
+<div class="card card-danger-outline text-xs-center">
+  <div class="card-block">
+    <blockquote class="card-blockquote">
+      <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Integer posuere erat a ante.</p>
+      <footer>Someone famous in <cite title="Source Title">Source Title</cite></footer>
+    </blockquote>
+  </div>
+</div>
+{% endexample %}
+
 ## Groups
 
 Use card groups to render cards as a single, attached element with equal width and height columns. By default, card groups use `display: table;` and `table-layout: fixed;` to achieve their uniform sizing. However, enabling [flexbox mode]({{ site.baseurl }}/getting-started/flexbox) can switch that to use `display: flex;` and provide the same effect.