Explanation
This formula uses two named ranges, "range1" (B5:B12) and "range2" (D5:D10).
The core of this formula is the COUNTIF function, which returns a count of each value in both range inside the AND function:
COUNTIF(range1,B5) // count in range1
COUNTIF(range2,B5) // count in range2
COUNTIF will either return zero (evaluated as FALSE) or a positive number (evaluated as TRUE) for each value in both ranges.
If both counts are positive (i.e. non-zero), the AND function will return TRUE and trigger the conditional format.