1.2.2. Grouping/Distinction by Format, 1.3. Immediate Feedback, 2.2. Information Density
The hierarchy of the menus and sub-menus needs to be clarified.
The sub-menu is visually larger than the main menu, which should dictate the sub-menu content.
Inverse the size of the menu and sub-menu.
The colors could also be switched, the attention being more drawn to the menu with the white background.