diff --git a/site/_docs/continuous-integration.md b/site/_docs/continuous-integration.md
index 17823e1b..0b671e21 100644
--- a/site/_docs/continuous-integration.md
+++ b/site/_docs/continuous-integration.md
@@ -158,9 +158,11 @@ environment variable `NOKOGIRI_USE_SYSTEM_LIBRARIES` to `true`.
 
 ### Exclude `vendor`
 
-Travis bundles all gems in the `vendor` directory on its build servers,
-which Jekyll will mistakenly read and explode on. To avoid this, exclude
-`vendor` in your `_config.yml`:
+<div class="note warning">
+  <h5>Be sure to exclude <code>vendor</code> from your <code>_config.yml</code></h5>
+  <p>Travis bundles all gems in the <code>vendor</code> directory on its build servers,
+which Jekyll will mistakenly read and explode on.</p>
+</div>
 
 {% highlight yaml %}
 exclude: [vendor]