Hey could anyone please give me the code in where when you highlight word blue and white (the normal colors) won't come out, instead you can use customize it with your own desired colors...
How do I do that?

As far as I know, you can't do that with CSS. I don't even think you can do it at all, as it's usually a setting that's set by the user in their computer's options panel. I know when I highlight text, the text is usually black, and the background color becomes a light gray.

However, I'll be incredibly surprised if it is possible. Like I said though, I really don't think it is.

Here's an example of a site that can customized the highlighting colors..
http://vanilla-moon.unwinded.com/

(Highlight the part on the left) See the green?

I never thought that would be possible-- it seems kind of frivolous.

Anyway, I found this page: http://www.quirksmode.org/css/selection.html

Using those codes will customize the selection.