Follow the next steps:
1. Add a query calculation containing a running-count summary eg running-count([Order_no])
2. Add a second query calculation as follows: mod([First calc],2)
3. Set up a boolean variable in the condition explorer with the expression [Second calc] > 0
4. Select ‘list columns body style’ using the Select Ancestor button, select the Style Variable property, and pick your boolean variable.
5. Hover your mouse over the Condition Explorer, select the ‘Yes’ variable value, then set the Background Colour property. Using the condition explorer, switch to the ‘No’ variable value and repeat using a different colour.
6. If your calculations exist in the query but are not shown in the list, select the list using the Select Ancestor button, go to the Properties property, and enable the calculations as properties of the list.