Characters or objects matching each other in color, or creating a sense of symmetry.
There must be multiple groups of separate colors to create the sense of "coordination". If there is only a single group with a single color, use color connection and the corresponding color theme tag instead. For instance, post #4734135 is yellow theme.
If there are multiple color groups but the characters are simply cosplaying and their matching pair isn't present (e.g. post #1490134), use color connection instead.
This technique is often associated with lineups or column lineups. When the columns are each completely monochromatically themed on a single color, it becomes multiple monochrome.
If the coordinated colors form a rainbow, it's also rainbow order.
