Hi @Marc Reed,
I think what is happening in the old Cognos charts is that the query and chart rendering occurs on the server side prior to the page rendering. Then the image of the chart is built and converted into a .png and saved on the server. Then the SVG for the client side chart uses this image as a background from which the svg polyline tags provide the interaction capabilities like tooltips, and highlighting, and axis labels with fonts etc. 
This makes it almost impossible to remove the borders through the Cognos UI because those CSS elements you want to manipulate have no client side connection to the chart settings.
The reason the axis label font color works is because it is rendered server side and configured in the report as a default available style for predetermined chart nodes like a category axis title or label.
The only way I can think to modify this would be to mess with the report specification and insert a custom CSS style attribute to a specific tag in the charts XML tags so at runtime the query passes the css class to the image renderer on the server. The only difficult thing is finding out what the class/id/name of those borders are in the backend and the way a report spec handles injected CSS for these charts means CSS selectors don't really work the same. I don't currently have the ability to check the server side files for the chart renderer code so I can't help you there but that is the first place I would look to modify this.
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Michael Webb
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Original Message:
Sent: Tue June 24, 2025 05:26 AM
From: Marc Reed
Subject: Cognos Charts with nested chart members - border formats
The only thing I have found is that the borders respect the axis label font colour.
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Marc Reed
Reporting Lead
Original Message:
Sent: Tue June 24, 2025 05:14 AM
From: Thomas Wolf
Subject: Cognos Charts with nested chart members - border formats
I gave up on that quite a while ago. Let's hope someone comes up with a genius idea.
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Thomas Wolf
BI Professional
Techniker Krankenkasse
Hamburg
Original Message:
Sent: Tue June 24, 2025 04:52 AM
From: Marc Reed
Subject: Cognos Charts with nested chart members - border formats
Hi all.
With a Cognos chart (the pre CA ones), when you nest members on an axis you have an option to display as nested or concatenated.
When you display as nested you end up with a chart that looks like :
Does anyone know of a method to control the borders draw around the nested members?
I have tried a few things but have never been able to change the borders from a solid black line. Given how many formatting options there are on a chart I must not have found the option that controls these borders. Normally these charts are so flexible and let you format anything, so it must be doable!
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Marc Reed
Reporting Lead
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