retro-futuristic 4-door chevy hhr fleetmaster, sleek black body, streamlined design with subtle curves, reduced bubble effect, large rounded headlights with integrated LED rings, bold fenders, refined chrome grille with vertical slats, aerodynamic roofline, low and wide stance, smooth doors seamlessly integrated, deep glossy black finish, chrome accents around windows and lights, sculpted rear with modern rounded taillights, jet-age-inspired design, futuristic yet classic, elegant and refined, four-door layout, sophisticated coupe silhouette, ultra-realistic textures, high-resolution, timeless design combining classic elegance with futuristic elements, subtle chrome highlights, powerful yet sleek appearance, (excessive curves:-1.5), (boxy design:-1.6), (supercar influence:-1.6), (flat shapes:-1.6), (over-the-top luxury cues:-1.5)