add src attribute to holder.js-powered <img>s so that they validate

use `data:` URL of empty invalid PNG: src="data:image/png;base64,"

1 files changed, 3 insertions, 3 deletions

diff --git a/css.html b/css.html
index 8b3cc0c50..d4d4c0335 100644
--- a/css.html
+++ b/css.html
@@ -2012,9 +2012,9 @@ For example, <code>&lt;section&gt;</code> should be wrapped as inline.
       <p>Keep in mind that Internet Explorer 8 lacks support for rounded corners.</p>
     </div>
     <div class="bs-example bs-example-images">
-      <img data-src="holder.js/140x140" class="img-rounded" alt="A generic square placeholder image with rounded corners">
-      <img data-src="holder.js/140x140" class="img-circle" alt="A generic square placeholder image where only the portion within the circle circumscribed about said square is visible">
-      <img data-src="holder.js/140x140" class="img-thumbnail" alt="A generic square placeholder image with a white border around it, making it resemble a photograph taken with an old instant camera">
+      <img data-src="holder.js/140x140" src="data:image/png;base64," class="img-rounded" alt="A generic square placeholder image with rounded corners">
+      <img data-src="holder.js/140x140" src="data:image/png;base64," class="img-circle" alt="A generic square placeholder image where only the portion within the circle circumscribed about said square is visible">
+      <img data-src="holder.js/140x140" src="data:image/png;base64," class="img-thumbnail" alt="A generic square placeholder image with a white border around it, making it resemble a photograph taken with an old instant camera">
     </div>
 {% highlight html %}
 <img src="..." alt="..." class="img-rounded">