I need to disable the highlighting of selected text on my web app. I have a good reason for doing this and know that this is generally a bad idea. But I need to do it anyway
I think you're looking for the :focus pseudo class. Try this:
input:focus {
background-color: #f0f;
}
It will give your input a pretty purple/pink color when selected.
I'm not sure which properties you have to (un)set, but I think you can find out yourself using trial and error.
Also note that the highlighting or absence thereof is browser specific!