CSS3: Chapter I & Chapter II & Chapter III

The first chapter:

1.<cite> tags can not only set the page as italic, but also to mark the title, making it easy to search by the search engine.

Chapter II:

1.import instruction Link Style sheet:

The CSS itself has a way to add an external style: @import instructions. Add this command to an HTML <style> tag, like this:

< style >     @import url (css/styles.css); </ style >

To place all @import rows before the CSS rule.

Chapter III:

1. Class selector naming allows only alphanumeric hyphens (-) and underscores (_), and the name must always start with a letter.

2. Class names are case-sensitive.

3. Pseudo-element: First-letter Select the first letter in the paragraph, fitst-line select the first line in the paragraph.

4.: Before and: Usage of After:

(1): Before can add content in front of the specified element. For example, to put "hot TIP" in the label containing the. Tip class, you can write this:

. Tip:before{content: "Hot tip! "}

(2): After can add content after the element.

5.::selection adds a style to text when you click and drag text, such as when you copy text, make the selected text white with a purple background, and add the following style:

:: selection{  color: #ffffff;  Background-color: #993366;    }

The selector can only set both the color and Background-color properties, and must use a double colon.

6. Pseudo-Class:

(1): First-of-type

Acts on a child element with a special label. For example, suppose you have a sidebar element that has a class name of sidebar. To define a style for the first paragraph in the sidebar, you can use this selector:

The. Sidebar P:first-of-type represents the first P label under the Sidebar class.

(2): Last-of-type

Contrary to: First-of-type effect.

(3): Nth-of-type

Used for specific label alternating sub-labels. Suppose you want to let the picture alternately float around, you can do it in the following two styles:

Img:nth-of-type (odd) {float:left;}

Img:nth-of-type (even) {float:right;}

CSS3: Chapter I & Chapter II & Chapter III