I'm a little confused as to the problem here. Most templating systems have a looping construct. They also allow you to know whether you're in an odd or even row. Just vary the background depending on the row number's modulo 2. Or, would that not work?

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We are the carpenters and bricklayers of the Information Age.

Don't go borrowing trouble. For programmers, this means Worry only about what you need to implement.

Please remember that I'm crufty and crochety. All opinions are purely mine and all code is untested, unless otherwise specified.