Let’s set the padding on the body element to a single unit of our baseline.

[annathefoodie.livejournal.com]

Let’s set the padding on the bodyelement to a single unit of our baseline.

Речь идет о плавающей типографике. Padding в данном случае отступ? Тогда вторая часть предложения не очень понятна. Unit здесь - это единиц измерения (em, rem)

With fluid typography, the baseline can be fluid, just like the font size. In fact, if we have already set the root element to a fluid value, we can use em or remunits, and we can use calc() to make this easy.

Let’s say we make 1.5rem our baseline. Let’s set the padding on the bodyelement to a single unit of our baseline.

We’ll do the same for the line height and margins.

For heading elements, I want a different line height. However, I want the height of the line plus the margins to equal an increment of the baseline. This is where calc() helps.