Mobile Menu Not Showing

Hello. First post and I'm really enjoying this theme. I'm using a freshly installed version of the theme and editing under a child theme on the latest version of WP. I have searched for this topic and tried the solutions but they've not worked. I'm having 2 issues: #1- the menu disappears in the mobile version, displays as it should on desktop & tablet. In Customise mode when I select mobile view it literally flies off the screen to the right, I've tried padding it but doesn't seem to do anything #2- I can't seem to identify the correct css class to change the orange hover colour in menus as a whole. Website address is: http://s827832082.websitehome.co.uk/ Any help you can provide will be great!