diff --git a/cdn.basic.css.inc b/cdn.basic.css.inc
index be7175d..457c0b9 100644
--- a/cdn.basic.css.inc
+++ b/cdn.basic.css.inc
@@ -152,5 +152,9 @@ function _cdn_build_css_path($matches, $base = NULL) {
     $path = preg_replace('`(^|/)(?!\.\./)([^/]+)/\.\./`', '$1', $path);
   }
 
+  // Ensure that $path begins with a /, so that file_create_url() does not
+  // try to encode the path with drupal_encode_path().
+  $path = '/' . ltrim($path, '/');
+
   return 'url(' . file_create_url($path) . ')';
 }