Python full stack development day37-css three introduction methods, base selector, advanced selector, supplemental selector

One, yesterday content Review Div: Split the whole site, lots of blocks

(1) Layout label

(2) block-level label exclusive line can be set high and wide, if not set width, the default is the width of the parent box

Span

(1) Small area (2) text label (3) display in one line, cannot place container class (block) box

(4) Width height cannot be set (5) Width height is related to span content

A:

(1) Text level label (2) cannot set high and wide (3) Hyperlink href: Connection resource title of mouse hover

Top of Jump:

<div id= ' top ' > <div>

.......

<a href= ' #top ' > Jump top <a>

Block the default event for a label

<a href = ' javascript:; ' > Jump Top <a>

<a hred = ' javascript:void (0); ' > Jump Top <a>

P:

(1) Paragraph label (2) Exclusive line (3) can only place text, pictures, form elements, cannot place container (block) (4) have margin

Img:

(1) Display content in one line (2) You can set the width height

SRC: Link Picture resource

ALT: The content displayed when a picture fails to load

Ul:ol, DL

Children are always Li

Li is a block-level label, exclusive line, can be set to a wide height, including any label

Form

XMLHttpRequest Object

: Interacting with the server

Type:text, submit, checkbox, ratio, button,

Select (option), Textarea,fieldset,

TABLE:TR\TD Ii. Summary of today's content 1 CSS Introduction

HTML: Structural standards

CSS: Style standard cascading style sheet cascading style sheet

Role: Define the effect of a Web page

JS: Behavioral Standards

　　　　

2 CSS three ways to introduce

1). Inline style

<p style= "color:red;" > Ju Pain </p>
Cons: Poor maintenance

2) inner-connection style

Style type= "Text/css" >
div{
Color:yellow;

}
p{
Color:black;
}
</style>

3) External style

LINK Type

<link rel= ' stylesheet ' type= "Texl/css" href= "./main.css" >

Import type

<style type= ' text/css ' >

@import url ('./main.css ')

</style>

3 Base selector for CSS * * * 1) Tag Selector

1. Check the label 2. No matter how deep the label is hidden, you can select 3. The selection is commonality, not the attribute

2) ID Selector

<!--only one ID value in a page--
<a href= "#" title= "id=" anchor "> Hyperlinks </a>

#anchor {
color:red;
}

3) class selector 4) wildcard selector 4 CSS Advanced Selector * *

1) descendant Selector

Div p{}

2) descendant Selector

div>p{}

3) and set selector

div,p,ul,ol{}

4) Intersection Selector

h3.active{}

5 CSS Supplement selector 1) Property selector 2) CSS3 selector Nth-child () 3) Pseudo class Selector

The code of Love and Hate
Remember A:hover.

4) pseudo element selector

p:after{

}

　　

Python full stack development day37-css three introduction methods, base selector, advanced selector, supplemental selector