diff --git a/src/Munee/Asset/Type/Css.php b/src/Munee/Asset/Type/Css.php
index <HASH>..<HASH> 100644
--- a/src/Munee/Asset/Type/Css.php
+++ b/src/Munee/Asset/Type/Css.php
@@ -173,7 +173,8 @@ class Css extends Type
         $changedContent = preg_replace_callback($regEx, function ($match) use ($originalFile, $webroot) {
             $filePath = trim($match[2]);
             // Skip conversion if the first character is a '/' since it's already an absolute path
-            if ($filePath[0] !== '/') {
+            // Also skip conversion if the string has an protocol in url
+            if ($filePath[0] !== '/' && strpos($filePath, '://') === false) {
                 $basePath = SUB_FOLDER  . str_replace($webroot, '', dirname($originalFile));
                 $basePathParts = array_reverse(array_filter(explode('/', $basePath)));
                 $numOfRecursiveDirs = substr_count($filePath, '../');
Ignore urls with protocols in CSS.