content/images.md: fix indentation in `picture` snippet.

diff --git a/docs/4.0/content/images.md b/docs/4.0/content/images.md
index 4601dcc6db5c7e32d67d9b77fd9cb7f013897f34..5c8e194708dd0d99d93862bcb295e8b9fcdc1668 100644 (file)
--- a/docs/4.0/content/images.md
+++ b/docs/4.0/content/images.md
@@ -77,7 +77,7 @@ If you are using the `<picture>` element to specify multiple `<source>` elements
 
 {% highlight html %}
 ​<picture>
- <source srcset="..." type="image/svg+xml">
- <img src="..."  class="img-fluid img-thumbnail" alt="...">
+  <source srcset="..." type="image/svg+xml">
+  <img src="..." class="img-fluid img-thumbnail" alt="...">
 </picture>
 {% endhighlight %}