I build small calculator tools that run entirely in the visitor's browser. One of them is a Canada overtime calculator, and it kept failing the same way on phones: the Pay column was cut off on the right, and the per-day table lost its last column too.

The first fix looked right. I gave the tables a fit-to-phone rule: fixed layout, full width, smaller padding, normal wrapping. It did not work. The screenshot after that fix showed the same cut-off columns.

There were two causes, and they stacked.

First, the hours were shown twice. A cell said 40.00 (40:00) , decimals and clock time in one cell. On a desktop that reads nicely.…