half correct. Your motherboard is definitely a micro atx, but the case specifies:
"Motherboard Compatibility: Micro ATX / ATX"
This will be the case with most atx cases. Generally case makers take the step to add holes for the smaller motherboards too. It's pretty much the standard that ATX cases will take mATX or atx, or Eatx cases will also take atx & matx, etc.
good on you for trying to at least understand it. The clearest answer is that YES this case will take your motherboard. ATX is the largest size it will take, but they also have the correct (extra) mounting points for a mATX motherboard, so that fits too. Mid-towers also tend to be the cheapest because smaller cases require special engineering and larger cases require more, and more expensive materials.. so mid-towers are the budget range.