[udemy]WebDevelopment

Your First CSS(Cascading Style Sheets)

Cascading means it always takes selector that is at the end 即后面的可以覆盖前面的。比如

在以下css文件中定义了两次 <p></p> 的颜色，最终它会呈现green。

 h2{

     color: red;

 }

 p{

     color: pink;

 }

 p{

     color: green;

 }

syntactic rule is very straightforward:

Selector{

    Property: value;

}

How to comment:

command + /

比如我们很喜欢某个网站的feature

we can right click

do'inspect'

我想<h2>Home</h2>变成红色，怎么办

 <!DOCTYPE html>

 <html>

 <head>

     <title>CSS learning</title>

 </head>

 <body>

     <header>

         <ul>

             <li>Home</li>

             <li><a href="about.html">About</a></li>

             <li><a href="login.html">login</a></li>

         </ul>

     </header>

     <section>

         <h2>Home</h2>

         <p>Lollll</p>

     </section>

 </body>

 </html>

新一个css文件

但是refresh之后，为何index.html的h2没变色？

Obviously

How does index.html know style.css exist ?

We need to link each other

So we add link in the <head></head>

 <!DOCTYPE html>

 <html>

 <head>

     <title>CSS learning</title>

     <link rel="stylesheet" type="text/css" href="style.css">

 </head>

 <body>

     <header>

         <ul>

             <li>Home</li>

             <li><a href="about.html">About</a></li>

             <li><a href="login.html">login</a></li>

         </ul>

     </header>

     <section>

         <h2>Home</h2>

         <p>Lollll</p>

     </section>

 </body>

 </html>

And make sure these two files in the same folder

we can create multiply style sheets

Beside <1>creating style.css file, we can also <2>'inline style' which is by specifying within the element

 <!DOCTYPE html>

 <html>

 <head>

     <title>CSS learning</title>

     <link rel="stylesheet" type="text/css" href="style.css">

 </head>

 <body>

     <header style="background-color: yellow">

         <ul>

             <li>Home</li>

             <li><a href="about.html">About</a></li>

             <li><a href="login.html">login</a></li>

         </ul>

     </header>

     <section>

         <h2>Home</h2>

         <p>Lollll</p>

     </section>

 </body>

 </html>

<3> using 'style' tags inside of <head></head>

 <!DOCTYPE html>

 <html>

 <head>

     <title>CSS learning</title>

     <link rel="stylesheet" type="text/css" href="style.css">

     <style >

         li{

             background-color: purple;

         }

     </style>

 </head>

 <body>

     <header style="background-color: yellow">

         <ul>

             <li>Home</li>

             <li><a href="about.html">About</a></li>

             <li><a href="login.html">login</a></li>

         </ul>

     </header>

     <section>

         <h2>Home</h2>

         <p>Lollll</p>

     </section>

 </body>

 </html>

CSS Properties

recommend website for CSS Properties : CSS Tricks

make your text in the center

text-align: center;

define the border

border: 5px solid purple;

add background image

/*本地图片*/

body{

    background-image: url(backgroundimage.jpg);

}

/*网上图片*/

body{

    background-image: url(www.unsplash.com/image2);

}

make background image fits the screen

body{

    background-image: url(www.unsplash.com/image2);

    background-size: cover;

}

add cursor(光标)

p{

    color: pink;

    cursor: pointer;

}

display in line

li{

    list-style: none;

    display: inline-block;

}

find the specific color: paletton.com

choose hex or RGB whichever way

h2{

    color: #AA9739;

    text-align: center;

    border: 5px solid rgb(170, 151, 57);

}

Cascading Style Sheets at the most basic level it indicates that the order of CSS rules matter.

.class

we can give any value we want, whatever we want to call it

<p class="webtext">Lollll</p>

.webtext{

    border:  5px dashed purple;

}

#id

similar to .class except that you can use only once

    <div id="div1">

            <p class="webtext">Lollll</p>

            <p>Lollll</p>

            <p>Lollll</p>

        </div>

#id{

    background: blue;

}

element

p{

    color: green;

}

element, element

h2, p {

    color: #AA9739;

    text-align: center;

    border: 5px solid rgb(170, 151, 57);

}

element element

I want you to select all 'p' s inside 'h2'

<h2>Home<p>Jennifer's home</p></h2>

h2  p {

    color: #AA9739;

    text-align: center;

    border: 5px solid rgb(170, 151, 57);

}

element > element

I want to select all 'p's that have a parent of 'h2'

h2 > p {

    color: #AA9739;

    text-align: center;

    border: 5px solid rgb(170, 151, 57);

}

element + element

I want to select any 'p' that is exactly after an 'h2' element

h2 + p {

    color: #AA9739;

    text-align: center;

    border: 5px solid rgb(170, 151, 57);

}

:hover

nothing happens but when I hover my mouse, it changes the style to what we just wrote down

h2 + p: hover{

    color: #AA9739;

    text-align: center;

    border: 5px solid rgb(170, 151, 57);

}

:last-child

only the last child of each webtext changes

.webtext:last-child{

    border:  5px dashed purple;

}

:first-child

same as last-child

!important (not recommended)

overrides any of the css rules and say, hey I don't care what anybody else says , 'p' should always be pink

p{

    color: pink !important;

    cursor: pointer;

}

p{

    color: green;

}

add underline to text

p{

    text-decoration: underline;

}

change text to uppercase

p{

    text-transform: uppercase;

}

make space between text

p{

    line-height: 20px;

}

change font style

font-family: "Times New Roman", Georgia; means if former one doesn't exist, pick the latter one

Use Google Fonts, we can add some specific fonts in own website

当然，这样会减慢你的网页反应速度

因为你的字体需要通过Google的链接响应

p{

    line-height: 20px;

    font-style: italic;

    font-weight: bold;

    font-size: 80%;

    font-family: "Times New Roman", Georgia;

}

add image

<img src="https://previews.123rf.com/images/tharun15/tharun151606/tharun15160600056/58764289-a-circular-geometric-design-for-summer-solstice-day-in-june-on-a-white-background.jpg"  width="50px" height="40">

critical render path

For now, sever is our computer

we request html

and the browser check I need css file

grab css file

hold on, the browser check I need font file

after that, it could render the page(display)

So you won't be able to render a web page until you receive css file and

sometimes font files you also have to wait for the font file to render the page

So if want your website faster, use your own font files and don't make css file too big

So you can enter you css code into minify CSS https://www.cleancss.com/css-minify/ to make it seem smaller

Flexbox

Flex 是 Flexible Box 的缩写，意为"弹性布局"，用来为盒状模型提供最大的灵活性。

https://css-tricks.com/snippets/css/a-guide-to-flexbox/

http://flexboxfroggy.com/

<!DOCTYPE html>

<html>

<head>

    <title>CSS</title>

    <link rel="stylesheet" type="text/css" href="style.css">

</head>

<body>

    <h1>Life in the wild</h1>

    <div class="container">

        <img src="https://static.pexels.com/photos/52500/horse-herd-fog-nature-52500.jpeg">

        <img src="https://static.pexels.com/photos/66898/elephant-cub-tsavo-kenya-66898.jpeg">

        <img src="https://static.pexels.com/photos/213399/pexels-photo-213399.jpeg">

        <img src="https://static.pexels.com/photos/158471/ibis-bird-red-animals-158471.jpeg

">

        <img src="https://static.pexels.com/photos/133459/pexels-photo-133459.jpeg">

        <img src="https://static.pexels.com/photos/50988/ape-berber-monkeys-mammal-affchen-50988.jpeg">

    </div>

</body>

</html>

.container{

    display: flex;

    flex-wrap: wrap;

    justify-content: center;

}

h1{

    font-family: fantasy;

    font-size: 3em;

    border-bottom: 2px solid pink;

    border-right: 2px solid pink;

    width: 400px;

    text-align: center;

}

img{

    width: 450px;

    height: 300px;

    margin: 10px;

}

Exercise

 <!DOCTYPE html>

 <html>

 <head>

     <title>RoboPage</title>

     <link rel="stylesheet" type="text/css" href="style.css">

     <link href="https://fonts.googleapis.com/css?family=Roboto" rel="stylesheet">

 </head>

 <body>

     <h1>Robot Friend</h1>

     <div class="robots">

         <div class="android">

             <div class="head">

                 <div class="eyes">

                     <div class="left_eye"></div>

                     <div class="right_eye"></div>

                 </div>

             </div>

             <div class="upper_body">

                 <div class="left_arm"></div>

                 <div class="torso"></div>

                 <div class="right_arm"></div>

             </div>

             <div class="lower_body">

                 <div class="left_leg"></div>

                 <div class="right_leg"></div>

             </div>

         </div>

     </div>

 </body>

 </html>

 h1 {

     text-align: center;

     font-family: 'Roboto', sans-serif;

 }

 .robots {

     flex-wrap: wrap;

     display: flex;

     justify-content: center;

 }

 .head,

 .left_arm,

 .torso,

 .right_arm,

 .left_leg,

 .right_leg {

      background-color: #5f93e8;

 }

 .head {

     width: 200px;

     margin: 0 auto;

     height: 150px;

     border-radius: 200px 200px 0 0;

     margin-bottom: 10px;

 } 

 .eyes {

     display: flex

 }

 .head:hover {

     width: 300px;

     transition: 1s ease-in-out;

 }

 .upper_body {

     width: 300px;

     height: 150px;

     display: flex;

 } 

 .left_arm, .right_arm {

     width: 40px;

     height: 125px;

     border-radius: 100px;

 } 

 .left_arm {

     margin-right: 10px;

 } 

 .right_arm {

     margin-left: 10px;

 } 

 .torso {

     width: 200px;

     height: 200px;

     border-radius: 0 0 50px 50px;

 } 

 .lower_body {

     width: 200px;

     height: 200px;

     /* This is another useful property. Hmm what do you think it does?*/

     margin: 0 auto;

     display: flex;

 } 

 .left_leg, .right_leg {

     width: 40px;

     height: 120px;

     border-radius: 0 0 100px 100px;

 } 

 .left_leg {

     margin-left: 45px;

 } 

 .left_leg:hover {

     -webkit-transform: rotate(20deg);

     -moz-transform: rotate(20deg);

     -o-transform: rotate(20deg);

     -ms-transform: rotate(20deg);

     transform: rotate(20deg);

 }

 .right_leg {

     margin-left: 30px;

 }

 .left_eye, .right_eye {

     width: 20px;

     height: 20px;

     border-radius: 15px;

     background-color: white;

 } 

 .left_eye {

     /* These properties are new and you haven't encountered

     in this course. Check out CSS Tricks to see what it does! */

     position: relative;

     top: 100px;

     left: 40px;

 } 

 .right_eye {

     position: relative;

     top: 100px;

     left: 120px;

 }

Responsive UI

should be a priority when building websites

It would show you what your website will look like on iPhone

Reponsive means your website, on no matter what platform, looks good, no cut-offs

[udemy]WebDevelopment_CSS的更多相关文章

Udemy上免费的angualr2视频教程分享
福利大分享本文作者:苏生米沿本文地址:http://blog.csdn.net/sushengmiyan/article/details/52592518 一晚上听了10几节课程,整体感觉很不错的 ...
[Udemy] Recommender Systems and Deep Learning in Python
1. Welcome 主要讲四部分内容: non-personized systems popularity: 基于流行度或者最大利益化的推荐. 缺点也明显:你可能在特殊地方有些特殊需求, 或者你本来 ...
Udemy - Angular 2 - The Complete Guide 笔记
1. install > npm install -g angular-cli 2. create app > ng new first-app 3. build app > cd ...
[udemy]WebDevelopment_HTML5
Build Your First Website 装一个subline text HTML default rule tags with opening and closing <!DOCTY ...
[udemy]WebDevelopment_History of The Web
WWW vs Internet For the begining, Internet was there. it was for the academics among universities Th ...
[udemy]WebDevelopment_How the Internet Works
Browsing the web Enter google.com, who is this google.com This question gets asked all the way down ...
[udemy]WebDevelopment_Bootstrap,Templates
Bootstrap Introduction Bootstrap 相对于CSS, JS 就像PPT模板相对于PPT 说白了就是前人已经做好了(pre-build)很多模板,你可以直接拿来主义 Boot ...
[Udemy] ES 7 and Elastic Stack - part 3
Section 7: Analyzing Log Data with the Elastic Stack
[Udemy] ES 7 and Elastic Stack - part 2
Section 3: Searching with Elasticsearch query with json 分页返回 Sort full text 的内容不能用来sort, 比如movie的 ti ...

随机推荐

Socket编程中检测端口是否被占用
一般检测一个端口是否被占用的方法是看bind是否成功,其实在Windows中有两个API可以获取到当前系统端口的占用情况(GetTcpTable/GetUdpTable),利用这两个函 ...
C++ wait捕捉的信号处理WIFEXITED/WEXITSTATUS/WIFSIGNALED
当一个进程正常或异常终止的时候,内核就像其父进程发送SIGCHLD信号,因为子进程是个异步事件,所以这种信号也是内核给那个父进程发的异步通知.父进程可以选择忽略该信号,或者提供一个该信号发生时即被调用 ...
把字符串中的空格替换为"%20"
这个需要注意的是字符串的结尾最后一个字符为'\0',并不是空字符,复制时要一块复制,算法思想就是先计算出字符串中总的空格数,然后重新计算字符串的长度,由于"%20"为3个字符,比 ...
bootstrap table教程--使用入门基本用法
笔者在查询bootstrap table资料的时候,看了很多文章,发觉很多文章都写了关于如何使用bootstrap table的例子,当然最好的例子还是官网.但是对于某部分技术人员来说,入门还是不够详 ...
【python】常用的日期和时间操作
#-*- coding: utf-8 -*- import datetime #给定日期向后N天的日期 def dateadd_day(days): d1 = datetime.datetime.no ...
配置 host only 后 nat不能上网了
如果只有nat 网关为nat 中设置的网关 eth0 启动第二块网卡host_only 网关就变成了 host_only中的网关 eth1 解决放法 route -n 看启用的是哪个网关 [roo ...
generatorConfig.xml
<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE generatorConfiguration ...
转转转！[Spring MVC] - 500/404错误处理-SimpleMappingExceptionResolver
参考博客: http://www.cnblogs.com/dongying/p/6129937.html http://www.cnblogs.com/rollenholt/archive/2012/ ...
[Android] 开发第五天
布之前开发的 Android 电话拨号器 Android-Studio 已经带了发布菜单, Build -> Generate Signed APK 进入发布界面我们新增一个证书,或者使用已有 ...
根据插件Swipe,结合jQuery封装成的新的jQuery插件
swipe支持电脑上的自动滑动,也支持手机端的滑动效果.但是每次调用只能支持一个效果或者说一个页面出现n个这样的效果,我们就得调用n次这个插件. 我使用swipe+jQuery使得swip变得方便使用 ...

[udemy]WebDevelopment_CSS

[udemy]WebDevelopment_CSS的更多相关文章

随机推荐

热门专题