My Japanese girlfriend said she’d be wearing a 振袖姿 for her coming-of-age ceremony next year. What kind of kimono is this? What can you tell me about it?

I’m not sure if it’s meant to be 振り袖姿 or 振袖姿. I think she used the latter. Currently, we do long distance, so I got sent this nugget in a Snapchat message which has now dusted away, unfortunately! By her tone, though, she seemed pretty passionate about this! I was wondering if you guys could help me understand it! I get the first two kanji to make up ふりそで　or long-sleeved kimono, but I’m not sure about the last kanji. Does it change the type of kimono? If so, in what way? What should I know? Am I asking this in the wrong subreddit? I’d love to know your thoughts! Thanks!!

by JalapenoMan999