Cross-section diagram of a fresco wall showing all layers in sequence from bottom to top. Bottom layer: rough red brick with mortar. Second layer: coarse gray plaster with visible large sand grains (0.5 cm particles). Third layer: smoother fine plaster with tiny sand grains (0.2 cm particles). Fourth layer: thin colored layer representing pigments bound with limewater (pale earth tones, slightly uneven). Fifth layer: very thin glossy layer representing tempera binder (egg emulsion) with brighter pigments. Top layer: transparent protective coating (subtle sheen). Each layer labeled with a small number (1,2,3,4,5,6) placed directly on the corresponding layer. No text words, only numbers. Clean white or light gray background. Technical illustration style, precise layers, clear boundaries between layers. Realistic materials texture. 16:9 aspect ratio.