Casdcading Style Sheets
A Cascading Style Sheet (CSS) provides the ability to separate the layout and styles of a web page from the data or information. Styles such as fonts, font sizes, margins, can be specified in one place, then the Web pages feed off this one master list, with the styles cascading throughout the page or an entire site.
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An internal style sheet should be used when a single document has a unique style. You define internal styles in the head section by using the <style> tag.
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An external style sheet is ideal when the style is applied to many pages. With an external style sheet, you can change the look of an entire Web site by changing one file. Each page must link to the style sheet using the <link> tag. The <link> tag goes inside the head section:
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