Center main-menu text items in mobile menu, with or without caret

Hi, the link below you will take you to a screenshot of the MOBILE version of the main menu for one of my WordPress sites (its URL is at the top of the screenshot):
https://drive.google.com/file/d/0B2FXLUvdhG4INmpGb3ljWG55OVU/view?usp=sharing

Note that the menu items are not consistently centered because some of them have a down-pointing caret and some don’t. Please provide the CSS I should add to the site’s child theme in order to center all these menu items, whether they have a caret or not.

Thanks!