My chickens are scared of what I wear sometimes?!?!

So its summer here where i live and its hot sometimes and i like to wear dresses on occasion i only recently started wearing dresses, in the past more often than not i wore shorts and a tank top i do now also and i raised my birds mostly wearing tank tops and shorts. anyway recently i went outside to take care of my chooks wearing this flowy longish mostly green dress it had brown spots and patterns on it of some other colors like white and black. when i walked outside and called them they kinda watched me and wanted to come near me cause they knew it was me but wasnt so i walked over to where they were and they freaked out and started flying everywhere and clucking and screaming and i was confused and finally figured out what it was they were scared of the dress. this happened once before but it was a long beige jacket that was sorta flowy also. Anyway does anyone know why they are afraid of this sort of stuff or habe hesrd of chickens being afraid or have any experience training them not to be afraid of this sorta stuff? Thank you.

It most likely makes you look bigger, and the movement scares them.
Just like cattle, they won't charge cause your wearing red, they will charge because they are scared and frightened.

Chickens are strange. I can run my mower by the coop and they don't so much as blink. I pick up a piece of wood to move it and they freak out.

I suspect it was the waving of the fabric. That movement would disturb them in the same way as waving your arms about would. To them, it would be like other birds flapping about. They'd assume there's something to be flapping about over.