Layerslider, menu and other problems

Greetings, layerslider is blank (I have 2 in the homepage). The thing is that the theme presents suddenly, (everything worked so far) some problems.

1. The menu items that have submenus don’t show the plus icon of the theme and when I hover the subitems don’t show
2. The problem with the hovering also happens in the backend where I can’t easily see the subitems of the sidebar
3. I have a comment area on the lower section for anyone to comment and now when you press the button comment it doesn’t do anything

There are other problems (for a week everything worked) but I wrote some for you to understand what’s happening.

Can you help me?