WeVividWeVividPick a colour from your light theme and get its dark-mode counterpart — lightness inverted and saturation tamed for a dark background.
Dark-mode counterparts roughly invert lightness and reduce saturation slightly, so bright, saturated light-theme colours don’t glare against a dark background.
A colour that reads well on white can look washed out or too intense on a near-black background — dark themes usually need slightly lighter, less saturated versions of brand colours.
It's a solid starting point based on common design practice, but always eyeball the result against your actual dark background and adjust if needed.