You could paint the walls and ceilings the same colour so they blend together.
你可以把这些墙和天花板漆成相同的颜色，这样它们就浑然一体。
《柯林斯英汉双解大词典》
2
It isn't just lizards that can use colour to blend into the background the spidery world also has many 8-legged chameleons including the four spot orb weaver and the crab spider.