Specificity
If you have two conflicting CSS rules that point to the same element, there are some basic rules that a browser follows to determine which one is most specific and therefore wins out. More Specific = Greater Precedence If the selectors are the same then the last one will always take precedence. p { color: red } p { color: blue } This will make the text blue. But look at this exit might seem that a p within a div would be colored blue, seeing as a rule to color p boxes blue comes last, but they would actually be colored red ample: div p { color: red } p { color: blue } In this example due to the specificity of the first selector. Basically, the more specific a selector, the more preference it will be given when it comes to conflicting styles.
Calculating Specificity
The actual specificity of a group of nested selectors takes some calculating. Basically, you give every ID selector (“#whatever”) a value of 100, every class selector (“.whatever”) a value of 10 and every HTML selector (“whatever”) a value of 1. Then you add them all up and hey presto, you have the specificity value. p has a specificity of 1 (1 HTML selector) div p has a specificity of 2 (2 HTML selectors, 1+1) .tree has a specificity of 10 (1 class selector) div p.tree has a specificity of 12 (2 HTML selectors + a class selector, 1+1+10) #baobab has a specificity of 100 (1 id selector) body #content .alternative p has a specificity of 112 (HTML selector + id selector + class selector + HTML selector, 1+100+10+1) So if all of these examples were used, div p.tree (with a specificity of 12) would win out over div p (with a specificity of 2) and body #content .alternative p would win out over all of them, regardless of the order.

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