SMOG / smog pollution

Air pollution is now a serious global environment problem,and the smog in Beijin, China is the most well known case.
At first, China goverment didn’t take this problem seriously and told people it’s safe, but of course, it’s not.
Thousands of people died because of smog, the element content in smog that harm human most is called PM2.5.
When haze up to a certain standard, the color will turn into yellow, and the color which most represent China is also yellow, so I changed the color of Temple of Heaven to yellow as well.