Ключевые слова: abstract, background, barrier, black, blue, border, braided, cage, chain, chained, close, design, element, enclose, enclosure, fence, freedom, graphic, green, grid, industrial, industry, iron, isolated, jail, keep, link, mesh, metal, nature, net, old, pattern, prison, protection, safety, security, shape, sky, steel, system, texture, tone, tree, up, wall, white, wire,