Description

Currently, the quick search panel has some visual problems regarding the UI like explained below:

• Waste of horizontal space for the categories names
• Lack of common visual elements, like border radius and back shadows
• Deviates a lot from standard Bootstrap elements
• It's not mobile friendly
• It's not using the Icon Theme

My proposal is to do a quick revamp of these visuals to better integrate with other standards of XWiki. 

Nota that here we don't have the "hide suggestions" button. Closing this component will be when:

• Choosing an option;
• Clicking/touching outside;
• Using the Esc button;

Intended Mobile View