Font Baseline Metrics in CSS & JavaScript

Demos:

• https://georgecrawford.com/portfolio/font-baseline
• https://georgecrawford.com/portfolio/font-baseline/fonts
• https://georgecrawford.com/portfolio/font-baseline/metrics

Based on an original idea by Alan Stearns

see also:

• http://stackoverflow.com/questions/23247467/how-css-line-height-is-measured
• http://blog.typekit.com/2010/07/14/font-metrics-and-vertical-space-in-css/
• http://static.zealous-studios.co.uk/projects/web_tests/line%20box.xhtml
• http://jeffyam.com/node/189
• https://mudcu.be/journal/2011/01/html5-typographic-metrics/#baselineCSS
• http://dev.labs.ft.com/george/baseline/
• http://christopheraue.net/2014/03/05/vertical-align/