abstract vintage background with colorful wavy lines in 60s-70s style. cool groovy backdrop. trendy cartoon banner template

illustration contemporary background decorative minimalist colourful wallpaper geometric nostalgia nostalgic abstract colorful backdrop template artistic creative ornament vintage cartoon minimal graphic pattern stripes artwork festive playful design 60s70s groovy trendy banner simple pastel vector poster colors joyful spiral lines style retro print cover twirl shape curvy funky 1980s party wavy cool line wave flow art 70s 60s