HTML5 Boilerplate: Default Browser Font Sizes
https://github.com/h5bp/html5-boilerplate/issues/825
IE8, Win7: font-size: 16px, line-height: 18px IE7, Vista: font-size: 16px, line-height: 18px Chrome 15, Mac: font-size: 16px, line-height: 18px Chrome 17, Mac: font-size: 16px, line-height: 18px Safari 5.1, Mac: font-size: 16px, line-height: 18px iPad 2, iOS5: font-size: 16px, line-height: 19px iPad 1, iOS4: font-size: 16px, line-height: 19px iPhone 4s, iOS5: font-size: 26px, line-height: 30px iPhone 3Gs, iOS4: font-size: 16px, line-height: 19px FF 7.0.1, Mac: font-size: 16px, line-height: 21px FF 8b, Mac: font-size: 16px, line-height: 21px FF 3.6 Mac: font-size: 16px, line-height: 16px