This is the 4012th most frequent Swedish word.
mörk
Dark.
In this sentence, 'mörkt' is used as an adjective to describe the color or shade of the hair.
Hennes hår är mörkt och glänsande.
Her hair is dark and shiny.
Here, 'mörk' acts as a descriptor for the noun 'natt' (night), illustrating a lack of light or brightness.
Det var en mörk natt med stormande vindar.
It was a dark night with stormy winds.
In this usage, 'mörk' forms a compound adjective 'mörkblå', indicating a specific shade of blue that is dark.