I'm loving these white sheers trimmed out in a dark shade (I think it's navy). While these curtains are likely custom ordered, why not hack this idea for yourself? If you're handy with a sewing machine, you'll know what to do. Non-sewers could use wide ribbon or edges-tucked-under fabrics strips and iron-on tape (used for hemming) or fabric glue. Ikea sheers are cheap, ribbon can be found cheap. Eye-catching and interesting window treatments are just a hack away!
P.S. Love the pale blue paint on the ceilings to add height to the white walls too.