adjust site url setting

src/client/js/components/Admin/App/SiteUrlSetting.jsx

@@ -43,7 +43,7 @@ class SiteUrlSetting extends React.Component {
           && (<p className="alert alert-danger"><i className="icon-exclamation"></i> {t('admin:app_setting.site_url_warn')}</p>)}
 
         <div className="row form-group">
-          <div className="col-9 offset-3">
+          <div className="col-md-9 offset-md-3">
             <table className="table settings-table">
               <colgroup>
                 <col className="from-db" />