Ключевые слова: alternative, art, blue, bolt, charge, conservation, contour, ecology, electric, electricity, element, energy, environment, environmental, flash, flat, generator, glowing, growth, icon, illustration, industry, isolated, leaf, leaves, light, line, linear, lineart, natural, neon, organic, outline, plant, power, reuse, seed, seedling, sign, storm, symbol, technology, thunder, turbine, white, windmill,