2.3.1 Set opening paragraphs flush left

The function of a paragraph indent is to mark a pause, setting the paragraph apart from what precedes it. If a paragraph is preceded by a title or subhead, the indent is superfluous and can therefore be omitted.”

Paragraphs, and other block level elements, are indented using the text-indent property. To ensure a paragraph is set flush left, the text-indent should be set to zero:

p {
  text-indent: 0;
}

This rule is rarely necessary, however, because CSS specifies that the default initial value for text-indent should be 0.

Rhythm & Proportion

§ Blocks & Paragraphs

Reference

Cover of ‘The Elements of Typographic Style’ by Robert Bringhurst