How HTML introduces CSS, and CSS selectors

Four ways to introduce CSS in HTML

1. Inline type

Style= "XXX" is written in the label

<= "color: #000;" >

2. Embedded type

Write the style tag in the head tag

< style >     H1{color:  #000; }</style>

3. Import type

Use @import= "Css_file" in the Style tab

< style >     @import "style.css"</style>

4. LINK Type

Using the link tag and href= "Css_file"

<rel= "stylesheet"  href= "Style.css " type ="" Media ="" />

Basic selector for CSS

1. Tag Selector: tagname{}

2. Category selector:. classname{}

3. ID selector: #idName {}

4. Wildcard: *{} means the element within the page

CSS Composite selector (Permissions: direct > Space > Comma)

1, intersection selection: Middle no space (between the basic selector)

Indicates that multiple selectors are satisfied

2. Set selection: separated by commas (",") (between basic selectors)

Indicates that the front and back selectors satisfy one of the

3. Descendant selection: separated by a space ("") (between the basic selectors)

Represents the latter in the former

Precedence in CSS

Style inline > #id样式 >.class style >tag styles

How HTML introduces CSS, and CSS selectors