A dark, brooding, and atmospheric digital painting in the style of a classic gothic horror book cover, 1024x1024 resolution. The central focus is an old, dilapidated Victorian mansion silhouetted against a stormy, twilight sky. Wisps of unnatural fog creep from the overgrown grounds towards the house. A single, dimly lit window on the upper floor glows with a faint, eerie light, hinting at secrets within. The color palette is dominated by deep indigos, bruised purples, stormy grays, and muted, ominous greens, with stark contrasts. The mood is one of dread, mystery, and encroaching darkness. The composition is dramatic and foreboding, with the house slightly off-center, drawing the viewer's eye towards the unsettling glow. The overall aesthetic should feel professional, evocative, and unsettling, suitable for a suspenseful thriller audiobook cover. Absolutely no text, letters, or logos.