I would like to say "A gradually will become B while you keep doing C" using "as" like this:
As I use it for a long time, it gradually becomes a treasure for me.
But I feel "as" requires a situation in which something gradually changes explained right after the word if a situation explained after comma also gradually changes. For example:
As it got darker, the winds blew stronger.
Could you please tell me how I can express the first sentence properly?