Floor-to-ceiling vertical blinds

I'd like to hang vertical blinds on my floor-to-ceiling windows (272 cm in height). Ceiling is concrete and has a rail already mounted.

The off the shelf solutions I see have mounts that are fixed to a wall, not to the ceiling.

• Can I fix a mount to the white window frame shown in the picture?
• If not, is it a good idea to remove the existing rail, and use the existing holes in the concrete to hang a mount for the vertical blinds mount? Perhaps with a right angle bracket?