Several menu items shown with grey background

Hello,
with iphone4 und Samsung S4 there are several menu items with a grey background, though these items weren't visited. There's no change in configuration. I have no idea what it could be. Can you help me?
Thx in advance.

Hi
give me your url
this is coming from the theme, on the :hover class and can be removed
CEd

this is in the file
plugins/system/accordeonmenumobileck/themes/default/accordeonmenuckmobile.css

line 48 on

.mobileaccordeonck div.accordeonck:hover, .mobileaccordeonck div.accordeonck:focus

you can remove the background color
CEd