Three, CSS
1.CSS basis
CSS representative of Cascading Style Sheets, is a document (modified HTML , XML and SVN language, etc.), you can beautify the presentation in the form of the document content.
CSS language is the core function of the value of the property for a specific set of characteristics of the format:
Attribute name : attribute value (e.g., color: #fff).
CSS declaration block is a plurality of CSS written together declaration, each CSS declaration by " ; " separated using a " { ", " } " multiple CSS declaration enclosed. In the CSS before adding a declaration block selector (e.g. div {width: 200px; background: Yellow;} ), is used to indicate the CSS statement on which the application element.
CSS acting on the HTML document There are three main ways:
( 1 ) Inline style sheet (adding element style properties, style attribute value css style rule)
( 2 ) internal style sheet (the style to the head tab style tag)
( 3 ) an external style sheet (the CSS rules written with a " .css " suffix to the file, and then use the HTML in the <link> tag CSS application files to HTML documents)