A background should sit behind the text, not in place of it. This paragraph lies on the tile at its true scale — if it reads without effort, the tile can go under content.
Concentric rings of magenta, green, yellow and cyan surround paired blue-cyan lobes arranged in four clusters around a small diamond at each tile's center, with diamonds and wavy outlines filling the gaps between tiles. The repeat steps across the grid in a regular, grid-aligned rhythm, so each tile's rings meet its neighbors' rings along the boundaries.
CC0 — use it for anything, no attribution needed. Read the FAQ