一 伪类选择器复习
注意点：
#1 a标签的伪类选择器可以单独出现，也可以一起出现
#2 a标签的伪类选择器如果一起出现，有严格的顺序要求，否则失效
编写的顺序必须要严格遵循： l v h a
a:link{
color: skyblue;
}
a:visited {
color: green;
} a:hover {
color: #e9289c;
} a:active {
color: pink;
}
二 过渡模块的基本使用
#1、过渡三要素
1.1 必须要有属性发生变量，如
div:hover {
width: 300px;
}
1.2 必须告诉系统哪个属性需要执行过渡效果
transition-property: width;
1.3 必须告诉系统过渡效果持续时长
transition-duration: 5s; #2、注意：
当多个属性需要同时执行过渡效果时，用逗号分隔即可
transition-property:width,background-color;
transition-duration: 5s,5s;
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title> <style>
* {
margin: 0;
padding: 0;
}
div {
width: 100px;
height: 50px;
background-color: red; /*
告诉系统哪个系统需要执行过渡效果
transition-property: width;
/*告诉系统过渡效果持续的时长
transition-duration: 5s; css是层叠样式表，这么写会跟上面的冲突，所以我们需要修改
transition-property: background-color;
transition-duration: 5s;
*/ transition-property:width,background-color;
transition-duration: 5s,5s;
} /*
hover这个伪类选择器除了可以用在a标签上，还可以用在任何其他的标签上
*/
div:hover {
width: 300px;
background-color: green;
}
</style>
</head>
<body>
<div></div>
</body>
</html>
示范
三 控制过渡的速度transition-timing-function
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
<style>
* {
margin: 0;
padding: 0;
}
div {
width: 100px;
height: 50px;
background-color: red; transition-property: width;
transition-duration: 5s; /*告诉系统延迟多少秒开始动画*/
transition-delay: 2s;
} div:hover {
width: 300px;
} ul {
width: 800px;
height: 500px;
margin: 0 auto;
background-color: pink;
border: 1px solid #000;
} ul li {
list-style: none;
width: 100px;
height: 50px;
margin-top: 50px;
background-color: blue; transition-property: margin-left;
transition-duration: 10s; } ul:hover li {
margin-left: 700px;
} ul li:nth-child(1) {
transition-timing-function: ease; } ul li:nth-child(2) {
transition-timing-function: linear; } ul li:nth-child(3) {
transition-timing-function: ease-in; } ul li:nth-child(4) {
transition-timing-function: ease-in-out; }
ul li:nth-child(5) {
transition-timing-function: ease-in-out; }
</style>
</head>
<body> <div></div> <ul>
<li>ease</li>
<li>linear</li>
<li>ease-in</li>
<li>ease-out</li>
<li>ease-in-out</li>
</ul> </body>
</html>
示范
四 过渡模块连写
#1 过渡属性连写
transition: 过渡属性 过渡时长 运动速度 延迟时间; #2 过渡连写注意点
2.1 和分开写一样，如果想给多个属性添加过渡效果也是用逗号隔开即可
2.2 连写的时间，可以省略后面的两个参数，因为只要编写了前面两个参数
就满足了过渡的三要素 2.3 如果多个属性运动的速度、延迟时间、持续时间都一样，那么可以简写为
transition: all 5s;
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
<style>
* {
margin: 0;
padding: 0;
}
div {
width: 100px;
height: 50px;
background-color: red; /*transition: width 5s linear 0s;*/
/*transition: width 5s linear 0s,background-color*/
/*5s linear 0s;*/ /*transition: width 5s,background-color 5s;*/
/*transition: width 5s,background-color,height 5s;*/ transition: all 5s; } div:hover {
width: 500px;
background-color: blue; height: 500px;
} </style>
</head>
<body>
<div></div>
</body>
</html>
示范
五 练习
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title> <style>
* {
margin: 0;
padding: 0;
} div {
height: 100px;
background-color: grey;
margin-top: 100px;
text-align: center; } span {
font-size: 50px;
line-height: 100px; transition: all 5s; } div:hover span {
margin-left: 50px;
} </style>
</head>
<body>
<div>
<span>EGON</span>
<span>是</span>
<span>讲</span>
<span>师</span>
<span>界</span>
<span>的</span>
<span>恐</span>
<span>怖</span>
<span>分</span>
<span>子</span>
</div>
</body>
</html>
弹性效果
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title> <style>
* {
margin: 0;
padding: 0;
} div {
width: 1000px;
height: 300px;
margin: 0 auto;
} img {
width: 200px;
height: 300px;
} ul {
width: 1000px;
height: 300px;
background-color: grey;
list-style: none;
margin: 100px auto; /*
最后一张图片超出了，因为每一张图片很大
但默认情况我们不想看到，所以剪裁掉多余
*/
overflow: hidden;
} ul li {
width: 100px;
height: 300px;
float: left; transition: all 0.3s;
} ul:hover li {
width: 88px;
} /*谁更具体谁的优先级更高，ul 下的li更具体，而ul可能指定有很多li*/
ul li:hover {
width: 200px;
} </style>
</head>
<body>
<div>
<ul>
<li><img src="https://images2018.cnblogs.com/blog/1036857/201805/1036857-20180516225724530-539090864.jpg" alt=""></li>
<li><img src="https://images2018.cnblogs.com/blog/1036857/201805/1036857-20180516225751362-1832630751.jpg" alt=""></li>
<li><img src="https://images2018.cnblogs.com/blog/1036857/201805/1036857-20180516225809591-1990809146.jpg" alt=""></li>
<li><img src="https://images2018.cnblogs.com/blog/1036857/201805/1036857-20180516225816920-580320384.jpg" alt=""></li>
<li><img src="https://images2018.cnblogs.com/blog/1036857/201805/1036857-20180516225828392-1011509025.jpg" alt=""></li>
<li><img src="https://images2018.cnblogs.com/blog/1036857/201805/1036857-20180516225836490-1526815653.jpg" alt=""></li>
<li><img src="https://images2018.cnblogs.com/blog/1036857/201805/1036857-20180516225847998-887601490.jpg" alt=""></li>
<li><img src="https://images2018.cnblogs.com/blog/1036857/201805/1036857-20180516225853390-460353134.jpg" alt=""></li>
<li><img src="https://images2018.cnblogs.com/blog/1036857/201805/1036857-20180516225859796-1981914722.jpg" alt=""></li>
<li><img src="https://images2018.cnblogs.com/blog/1036857/201805/1036857-20180516225906468-571800433.jpg" alt=""></li>
</ul>
</div>
</body>
</html>
手风琴效果
