gradient shahmatnuy
background-image: repeating-linear-gradient(45deg, transparent 12px, transparent 27px, red 20px, red 30px, transparent 30px, transparent 49px, red 40px, red 53px, transparent 53px), repeating-linear-gradient(-45deg, transparent 8px, transparent 27px, red 20px, red 30px, transparent 30px, transparent 47px, red 40px, red 50px, transparent 50px)