In Beijing, I was told "Blue is for the Heavens, yellow is for the Emperor, green for the Empress, and grey for the people". Beijing is nothing if not sensory overload, but the colors mostly are the same. Blue is usually bright cobalt blue (except for beautiful ultramarine tiled roofs) and red is always bright red, "the color of blood". Buildings are a soft warm grey.
The yellow spiky fruit on the right is durian, which has a smell so objectionable it is banned from hotels and public transportation in Southeast Asia (but maybe not in China). A friend called it 'corpse fruit'.
When my father visited mainland China in 1980, it was so filthy they couldn't use the towels and brushed their teeth with Scotch whiskey. Not anymore. The parts of Beijing a tourist is apt to see are spotless. The Beijing airport, with its spit-and-polish officials, make most US airports look even worse than you thought. 
The Ishtar Gate on display is the smaller of two gates erected in Babylon around 575 BC. The gate is constructed of bright blue ceramic tile that was excavated in the 1930s; one wonders how they dug this out. This gate is roughly 45 feet high, and extends through a long gallery. The larger gate is in storage. 
