Ключевые слова: alternative, art, battery, blue, charge, clean, color, colorful, concept, contour, design, eco, ecological, ecology, electric, electrical, electricity, element, energy, environment, environmental, global, green, icon, illustration, isolated, leaf, light, line, linear, lineart, modern, natural, nature, object, outline, plant, power, recycle, recycling, renewable, sign, single, symbol, technology,