How to apply a formula to visible columns only?

问题

I need the formula to ignore a range if it`s hidden. I know that there is 'SUBTOTAL' that works for rows, but in my case, I need something for columns. I also tried to go with 'CELL("width")' with no luck.

Here is the sample spreadsheet: https://docs.google.com/spreadsheets/d/10BNrnAyQw89gy-Sj3CLiz4AgVtFI0AjXTvc0REGGTfY/edit?usp=sharing

Is there any other option to ignore hidden columns in a count formula?

来源：https://stackoverflow.com/questions/63241198/how-to-apply-a-formula-to-visible-columns-only