Create a dreamy abstract background that represents a foggy cityscape at twilight. The design should feature a harmonious blend of deep blues, soft purples, and gentle pinks, creating a serene atmosphere. Use flowing, abstract forms to suggest the outlines of buildings and streets, all softened by layers of mist. The lighting should be subtle, with a focus on creating a luminous glow that emanates from within the fog, hinting at the life and energy of the city. Incorporate a slight texture to the background to evoke the feeling of depth and movement, allowing the viewer to feel as if they are peering into a tranquil, fog-laden urban landscape.