Add custom colors for stacks/columns

Hi.

Currently, it is possible to visually highlight individual cards using colors. However, stacks (columns/lists) cannot be assigned a custom color.

It would be helpful to allow users to choose a color for each stack, for example by adding a colored header, border, or background. This would significantly elevate the readability, make (especially) larger boards easier to navigate and allow different workflow stages or categories to be distinguished more quickly.

Is support for custom stack colors already planned or being considered?

Possible use cases:

• Visually distinguishing workflow stages
• Highlighting important or blocked sections
• Grouping stacks by topic, team, or priority
• Improving readability on boards with many stacks

Thank you!

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No file or test is named in the issue. Start by locating the existing card-color implementation and the stack/column rendering and editing entry points, then determine how a stack color would be selected and stored. Done should mean users can assign a custom color to each stack and see it consistently on the board.