My mom, who is 46, won't stop rearranging my stuff.

If something is placed in a specific location in my room, it's because that's the most convenient spot for me to keep it, even if it might not look perfectly organized. (And yes, I do try to maintain a presentable space.) It's nothing extreme; I usually just keep certain items within reach of my bed and desk. However, my mother often rearranges things in my room according to her preferences, claiming it makes the space "presentable" (but for whom?). She never tells me when she does this, leaving me to discover the changes on my own. Whenever I bring this up, she responds in the same way. She denies doing anything, and when I point out her changes, she claims she only moved a few things. When I highlight even more alterations that bother me, she either insists I should be grateful for her "cleaning" my room or mocks me for getting upset over minor issues. If she ever admits to her actions and promises to stop, I inevitably catch her doing the same thing again just a few days later. It's nothing major, nor am I trying to hide anything; it's simply frustrating and inconvenient for me. I feel powerless since she can easily dismiss any concerns I raise. I’ve even tried rearranging things myself to see how she likes it (I admit, it's a bit childish), but she seems unfazed. What can I do to put an end to this behavior?