Conditional Formatting Columns based off Cell Input

Hello all-

Instructions are in the attached excel as well. Please see attached

If a person puts in a price in column A, that results in column B "Everyday Price Per Unit" being greater than column C "NDP", then highlight column A cell input red.

=Column B>Column C, then turn input cells in Column A Red.

First four highlighted are examples of thise formula scenario

** All based off an input into column

Does anybody know how to use conditional formatting to do so???