1, analysis: A dark room means "darkroom", plus "every" and "light" to form a darkroom, and every lamp is on.

2, interpretation: metaphor in distress or confusion, suddenly encountered rescue or guidance.

Synonym: send charcoal in the snow? Never cross the river?

Idiom: Your suggestion makes me feel like a dark room with lights on.

3. Idioms with dark characters are:

Sneaking into a secret place is a metaphor, using fake images to achieve a certain purpose. It is also a metaphor for adultery.

An arrow in the back is hard to prevent, and an arrow in the back is the most difficult to prevent. Metaphor intrigue, hard to prevent.

Darkrooms don't bully people, and they don't do shady things where no one sees them.