（图片来源：wiki）
参考资料：
[1]https://www.livescience.com/6679-clean-dirty-keyboard.html
[2]https://home.howstuffworks.com/home-improvement/household-hints-tips/cleaning-organizing/germier-than-your-toilet-clean-your-keyboard-now2.htm
[3]https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6210060/
[4]https://abcnews.go.com/Health/Healthday/story?id=4509937&page=1
