diff --git a/core/template.php b/core/template.php
index 2f2e442..f9e546b 100644
--- a/core/template.php
+++ b/core/template.php
@@ -148,6 +148,7 @@ function om_preprocess_page(&$vars) {
   }
   // aggregate css files
   $preprocess_css = variable_get('preprocess_css', 0);
+  $query_string = '?' . substr(variable_get('css_js_query_string', '0'), 0, 1);
   if (!$preprocess_css) {
     $styles = '';
     foreach ($vars['css'] as $media => $types) {
@@ -155,7 +156,7 @@ function om_preprocess_page(&$vars) {
       $counter = 0;
       foreach ($types as $files) {
         foreach ($files as $css => $preprocess) {
-          $import .= '@import "'. base_path() . $css .'";'."\n";
+          $import .= '@import "'. base_path() . $css . $query_string .'";'."\n";
           $counter++;
           if ($counter == 15) {
             $styles .= "\n".'<style type="text/css" media="'. $media .'">'."\n". $import .'</style>';