Dan -- This problem tends to crop up when folks don't leave well enough alone. I suggest you stick with 0 (zero) as the display width for everything and let your browser scale the columns as best it can. This generally will give the best performance on a largest variety of devices (phones/tablets/desktop).
If you choose to ignore this advice and specify something anyway, keep in mind that Display Width is in
pixels, not characters or percent.
Hope this helps,
Bruce
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