Catch Evolution Pro – Problem by displaying on Tablet

Dear all, Since few time I am facing a small problem with the graphics displaying the site on the tablet (in horizzontal position): In shortly, the last button of the menu (9 pieces at all) will be not displayed on the same menu-line but rather in an additional second line below (unwanted) and the width of right part of the the header-image will be reduced. In it place will be displayed the background color of the website. Otherwise, displaying on PC or Mobile phone is OK ! Have you got an idea where I could modify/change something to solve this issue? At best, please take a look on the website ( www.astrolive.ch ) yourself ! Please, let me know if you need more infos about this issue!