RGB circuit - 12VDC

Hi Forum,

Apologies for the newbie questions here…

Scenario - planning to setup a backlit illuminated panel for the car (carling switches -12VDC). The backlit panel will be illuminated via LEDs-

the objective:

if possible would the to use a sequence of RGB LEDS which change colour depending on corresponding Carling (rocker) switch position.

the resting backlight would be Blue (which is handy) but i want to colour to change based on the switch (some are SPST, some are SPDT), Which would mean at some level the RGB led would operate independently. (with an inline resistor for 12VDC or do this via the common earth - see below)

Secondary control LED brightness - have i got this wrong but i can use the common ground via a PWM to set brightness across all LEDS whilst the 12VDC will operate the RGB led?