How to change my log on screen and boot skin.?

I am not going to tamper with the computer files or anything like that.

I don't know if there is a simple program or a simple and non-risk way to do this but if there is I would like to know how.



Please, do not answer with things that need code or change the system in any way. If there is no other way then Oh well.



Thanks!



Ps. if you know of a place where I can download or make my own that would be great.



I am specifically looking for (resident evil's) Umbrella corp. type log on etc.

Thanks!How to change my log on screen and boot skin.?
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