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The first step is to calculate the value for column a, which we??™ve done in Table 5.1.
If the style rule is specified within the element??™s HTML style attribute, a should
equal 1; otherwise, it should equal 0. In fact, this is the only case where there is a
value in column a.
129 The Cascade, Specificity, and Inheritance
Table 5.1: Inline Style: Column a = 1
Element Types and
Pseudo-elements
Classes, Attributes, and
Pseudo-classes
IDs Inline Style
0 0 0 1
As you can see, an inline style rule will always have a specificity of 1,0,0,0??”the
highest level of specificity. Here??™s an example of such a style rule:

Red Text

This is one of the reasons why inline styles should be avoided. As inline style rules
always have the highest specificity, the only way to overwrite them within the CSS
cascade is to use the !important statement (p. 124) on the relevant declarations??”an
approach that creates a maintenance nightmare.
For rules other than inline styles, we need to calculate columns b, c, and d.


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