Specificity describes the weight of a selector and any declarations associated with it. The following table summarizes the components of specificity summation.

Specificity values are cumulative; thus, a selector containing two element identifiers and a class identifier (e.g., div.aside p) has a specificity of 0,0,1,2. Specificity values are sorted in right-to-left precedence; thus, a selector containing 11 element identifiers (0,0,0,11) has a lower specificity than a selector containing just a single class identifier (0,0,1,0).

The !important directive gives a declaration more weight than nonimportant declarations. The declaration retains the specificity of its selectors and is used only in comparison with other important declarations.