In this apartment in St. Petersburg, the tones chosen for the furnishings and finishes are certainly harbingers of brightness or multi-colored: dark tones predominate in fact, with however a lighting system worth noting.
Also the use of reflective surfaces, such as graphite ceilings, or iridescent, pearl-like effect, which changes color depending on how light is reflected, gives every room a special charm.
Also note the tendency of a Japanese artist chosen for the bathroom, the only decorative note in an apartment understated elegance.