Sure, shadows can be a mood lever, but they’re still just light hitting a plane. If you want melancholy, use long, low angles that funnel the eye toward a single dark corner—think a vertical choke point. Drop a foam cube there, give it a jagged edge, and watch the path twist into a sad story. Don’t add random plants or soft rugs, they’ll break the flow and you’ll get a burnout loop of re‑ordering. Stick to clean lines, let the light do the drama, and the room will feel sad without being a cluttered mess.