LED switching

Good day I really need help on a tricky topic for me. I’ve been reading about it for days now but I just don’t get smart! You’re my last hope and hope you can help me on the subject! I have the following plans: I wanted to make a kind of ambient lighting for the doors for my car. I already have everything I need here. But now I still lack a suitable circuit. I plan to equip the ambient lighting with 2 LEDs, one discreet blue and a bright white. And the whole thing should look like this: -door closed, dipped light on, the blue LED light on -deep light on, door opened, blue LED goes out abruptly and the white LED goes off abruptly, so blue 100% on 0% and white 0% on 100% dipped light, door closed, white LED dimmes slowly darker while the blue LED at the same time slowly dimmes to full brightness I hope you can follow my thoughts. I already have a touch n stuff read in the net about PWM dimming etc… but as far as I’m concerned, I’m pretty layman and what is described there is backwards for me like Chinese. It’s all described only for experts, but not for newcomers What I would need would be a list of needed components and a sketch of how the circuit is built up. Soldering is on it. So what the board would need would be an input for +12V, one for mass, one for the signal of the door warning light and 2 outputs for the two LEDs. I am grateful to you for any help and wish you a nice Valentine’s Day MfG Christopher