Ключевые слова: aqua, arrow, art, banner, bin, bio, can, clean, color, colorful, contour, danger, drop, eco, ecology, electric, energy, environment, environmental, faucet, garbage, hand, hazard, icon, illustration, isolated, leaf, line, linear, natural, nature, outline, planet, plastic, pop, popart, problem, recycle, recycling, reload, set, sign, symbol, tag, toxic, water, world,