I want to change the CSS style when a WinJS Listivew item is selected, like in the picture.
Basically I would like the purple part to be grey, and this should to be done via CSS I guess because we are in WinJS.
win-selectionborder
win-selectionbackground
win-selectionhint
win-selectioncheckmark
win-selectioncheckmarkbackground
I've tried them all, but they all give strange results, changing everything but that.
Here are the images from Chapter 5 of my free ebook, Programming Windows Store Apps with HTML, CSS, and JavaScript, Second Edition, where I show how all the styles related to the checkbox. These are specifically in the section called "Styling Gallery: WinJS Controls". In these images I show the default styling as compared with custom styling. You'll see that the trick is really having the right selectors for the styling hierarchy, as it's often not just a single class you have to concern yourself with. Note also that the use of .win-selectionstylefilled distinguishes between that and the outline style.
Also note that the styles I show here are not scoped to a particular list or page; gbellman's answer gives some of that.