Great book! I was a bit thrown off by this though, at the end of "Applying Relative Layout Units" - font and line-height are set here:
and usage here:
font: normal 100% Helvetica, Arial, sans-serif; /* 16px */
but then there is an immediate jump of logic to this:
font-size: 0.75em; /* 12px */
padding: 0.5em; /* 6px */
the explanation given is:
font: normal inherit 400 1em/1.5 Helvetica, Arial, sans-serif;
It's a bit vague. Is this another example of the same p tag written like this? This is the first use of 'inherit' and I'm not sure how the number 400 was arrived at and what is 1em/1.5 doing as a CSS selector? And why is the font family in there at all when it's already in the body tag?
The simple formula (target ÷ context = result) we used for generating relative font sizes is going to come to our rescue once more with our fluid grid solution.