Historical Context in The Metamorphosis
In the early 20th century, people still used gas lamps in their houses. Here, Kafka contrasts the warm, comforting glow of the gas lamps in the living room with the pale, electric light of the street lamps Gregor noticed on the ceiling of his room. This use of light divides the two rooms, making one seem like a place of warmth and togetherness and the other a tiny room of darkness and misery.
In the early 20th century, a woman's neck was generally covered by a collar or a scarf as a sign of modesty, but women in the work force, who weren't typically thought of as ladies, sometimes went without it. Grete's change in wardrobe should be understood as another kind of transformation, one that traces her development from a young, often thoughtless woman to an adult who's making her way in the world.