vintage-style pi day banner with old-school mathematical notations

pi day mathematics math background symbol geometric pattern abstract design digital wallpaper equations mathematical art futuristic theme neon glow minimalist chalkboard style galaxy golden ratio number sequence educational poster infographics diy craft handmade gift creative typography vintage notations circular printable chart maththemed banner geeky handdrawn elements sticker icon set scientific symbols fun formula celebration equation stem geek culture academic nerdy science graphic vector