line-height property is defined by the spec in the following way:
On a block container element whose content is composed of inline-level elements,
line-heightspecifies the minimal height of line boxes within the element. The minimum height consists of a minimum height above the baseline and a minimum depth below it ...
So there is a base font size of text, which amounts to 1em, a vertical space between the ascent and descent lines, and the line-height is designed to extend this space.
Are there any rules that calculate what a specific place at the extended line box the text, limited by the 1em space, must take? I mean this possible distinction:
(all the free space is just put below the text)
(the free space is allocated proportionally)
It seems that the second option is in use (jsfiddle) but I want to find out the specific rules of space allocation, or they are unspecified exactly?
