Slate-blue, white and light to medium shades of wood are great colour combos to promote the serenity of a bedroom. This one is also rich in textural difference, from the sleek gloss of what looks like polished concrete, to the wood texture, to the soft throw and upholstered mid-century chair.
This room is very restrained and coordinated in its colour usage. For instance, that great chair has a white frame behind the great slate-blue upholstery.
The blue throw at the foot of the bed perfectly balances all the white bed linens. There is a rather unusual approach to art on the wall behind the headboard: It looks to me like small cubes (but can't tell for sure)