set of paper mockup cards with colorful polygonal backgrounds. made of shiny triangles for invitation, web pages, apps, party

red blue silver purple violet orange paper card set gold grey golden white shiny triangles polygonal triangular year winter empty space copy textured metallic foil bright vector background geometric polygon abstract modern design shape pattern mosaic triangle template futuristic luxury wallpaper texture graphic decoration yellow geometry mockup cards colorful backgrounds invitation web pages apps party flyer simple design