Why does font ignore line-height in CSS while font-size doesn't?

Why does font ignore line-height in CSS while font-size doesn't?

pI experienced a very weird behavior. Why does test2 ignore line-height
while test1 works fine? (the background-color is just to identify the
containers better)/p precodebody { line-height:0.8; } .test1 {
background:#fdf; font-size:24px; font-family:Arial,sans-serif; } .test2 {
background:#ffd; font:24px Arial,sans-serif; } /code/pre plive demo: a
href=http://jsfiddle.net/tHUeg/4/
rel=nofollowhttp://jsfiddle.net/tHUeg/4//a/p