No, it's implied that it's a multiple if the font size. In ems, basically.

On 13 Aug 2013, at 09:41 PM, Jack Franklin <notifications@github.com> wrote:

> In css/styles.css:
> 
> > @@ -43,6 +43,7 @@ h1 {
> >  
> >  p, .entry-content ul {
> >    margin-bottom: 1.5em;
> > +  line-height: 1.95;
> excuse my idiocy, but does this not need a unit?!
> 
> —
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