Honestly, through a combination of Madoka being too busy staring back for the last time at the place they're leaving while getting on the train and the fact that Evie is uttering the spell under her breath, Madoka doesn't even notice that the other is casting a spell to begin with. All she notices is that when she turns to look into the train instead as she's boarding it, there's suddenly hair changing in front of her eyes.

Fairly mild compared to everything she's seen the past while, but still enough to startle her when it comes out of the blue like that.

"Oh--! Are you okay?" Not like she can tell Evie actually did that herself rather than it being some random thing happening to her.