abstract air-bubbles air-pockets appearance backgrounds blue bubble bubble-plastic bubbles colorful colourful cool cushioned cushioning cushioning-material dark firm light perspectives plastic plastic-bubble-technology protection protective roll shapes sheets surface surfaces texture textured textures wallpaper Australian background bare bark branches brown colors colours contours cream edges gnarled layers lines Melaleuca mottled paperbark paperbark tree shadows shedding soft sunlight tree tree trunk trunk uneven variations wood