- <!DOCTYPE html>
- <html lang="en">
- <head>
- <meta charset="UTF-8">
- <meta http-equiv="X-UA-Compatible" content="IE=edge">
- <meta name="viewport" content="width=device-width, initial-scale=1.0">
- <title>Document</title>
- <style>
- /* 找到div的儿子p设置文字颜色是红色 */
- /* 父选择器 后代选择器 {} */
- div p {
- color: red;
- }
- </style>
- </head>
- <body>
- <!-- 后代: 儿子, 孙子, 重孙子..... -->
- <p>这是一个p标签</p>
- <div>
- <p>这是div的儿子p</p>
- </div>
- </body>
- </html>
-
- <!DOCTYPE html>
- <html lang="en">
- <head>
- <meta charset="UTF-8">
- <meta http-equiv="X-UA-Compatible" content="IE=edge">
- <meta name="viewport" content="width=device-width, initial-scale=1.0">
- <title>Document</title>
- <style>
- /* 空格隔开的是后代, 儿子,孙子,重孙子 */
- /* div a {
- color: red;
- } */
-
- /* 只想选中儿子a */
- /* div的儿子a文字颜色是红色 */
- div>a {
- color: red;
- }
- </style>
- </head>
- <body>
- <div>
- 父级
- <a href="#">这是div里面的a</a>
- <p>
- <a href="#">这是div里面的p里面的a</a>
- </p>
- </div>
- </body>
- </html>
-
- <!DOCTYPE html>
- <html lang="en">
- <head>
- <meta charset="UTF-8">
- <meta http-equiv="X-UA-Compatible" content="IE=edge">
- <meta name="viewport" content="width=device-width, initial-scale=1.0">
- <title>Document</title>
- <style>
- /* p div span h1 文字颜色是红色 */
- /* 选择器1, 选择器2 {} */
- p,
- div,
- span,
- h1 {
- color: red;
- }
- </style>
- </head>
- <body>
- <p>ppp</p>
- <div>div</div>
- <span>span</span>
- <h1>h1</h1>
-
- <h2>h2</h2>
- </body>
- </html>
-
- <!DOCTYPE html>
- <html lang="en">
- <head>
- <meta charset="UTF-8">
- <meta http-equiv="X-UA-Compatible" content="IE=edge">
- <meta name="viewport" content="width=device-width, initial-scale=1.0">
- <title>Document</title>
- <style>
- /* p {
- color: red;
- } */
-
- /* .box {
- color: red;
- } */
-
- /* 必须是p标签,而且添加了box类 */
- /* p.box {
- color: red;
- } */
- /* #dilireba {
- color: red;
- } */
-
- .box1 {
- color: green;
- }
- </style>
- </head>
- <body>
- <!-- 找到第一个p,带box类的, 设置文字颜色是红色 -->
- <p class="box box1" id="dilireba">这是p标签:box</p>
- <p class="box">这是p标签:box</p>
- <p>pppppp</p>
- <div class="box">这是div标签:box</div>
- </body>
- </html>
-
- <!DOCTYPE html>
- <html lang="en">
- <head>
- <meta charset="UTF-8">
- <meta http-equiv="X-UA-Compatible" content="IE=edge">
- <meta name="viewport" content="width=device-width, initial-scale=1.0">
- <title>Document</title>
- <style>
- /* 悬停的时候文字颜色是红色 */
- a:hover {
- color: red;
- background-color: green;
- }
-
- /* 用户鼠标悬停到div的时候, 文字是绿色 */
- div:hover {
- color: green;
- }
- </style>
- </head>
- <body>
- <a href="#">这是超链接</a>
- <!-- 任何标签都可以添加伪类, 任何一个标签都可以鼠标悬停 -->
- <div>div</div>
- </body>
- </html>
-
- <!DOCTYPE html>
- <html lang="en">
- <head>
- <meta charset="UTF-8">
- <meta http-equiv="X-UA-Compatible" content="IE=edge">
- <meta name="viewport" content="width=device-width, initial-scale=1.0">
- <title>Document</title>
- <style>
- div {
- width: 400px;
- height: 400px;
- /* background-color: pink; */
- /* background-color: #ccc; */
- /* 红绿蓝三原色, a是透明度0-1 */
- /* background-color: rgba(0, 0, 0, 0.5); */
- background-color: rgba(0, 0, 0, .5);
- }
- </style>
- </head>
- <body>
- <div>div</div>
- </body>
- </html>
-
- <!DOCTYPE html>
- <html lang="en">
- <head>
- <meta charset="UTF-8">
- <meta http-equiv="X-UA-Compatible" content="IE=edge">
- <meta name="viewport" content="width=device-width, initial-scale=1.0">
- <title>Document</title>
- <style>
- div {
- width: 400px;
- height: 400px;
- background-color: pink;
- background-image: url(./images/1.jpg);
- }
- </style>
- </head>
- <body>
- <div>文字</div>
- </body>
- </html>
-
- <!DOCTYPE html>
- <html lang="en">
- <head>
- <meta charset="UTF-8">
- <meta http-equiv="X-UA-Compatible" content="IE=edge">
- <meta name="viewport" content="width=device-width, initial-scale=1.0">
- <title>Document</title>
- <style>
- div {
- width: 400px;
- height: 400px;
- background-color: pink;
- background-image: url(./images/1.jpg);
- /* background-repeat: repeat; */
- /* 不平铺: 图片只显示一个 */
- /* background-repeat: no-repeat; */
- /* background-repeat: repeat-x; */
- /* background-repeat: repeat-y; */
- }
- </style>
- </head>
- <body>
- <div>文字</div>
- </body>
- </html>
-
- <!DOCTYPE html>
- <html lang="en">
- <head>
- <meta charset="UTF-8">
- <meta http-equiv="X-UA-Compatible" content="IE=edge">
- <meta name="viewport" content="width=device-width, initial-scale=1.0">
- <title>Document</title>
- <style>
- div {
- width: 400px;
- height: 400px;
- background-color: pink;
- background-image: url(./images/1.jpg);
- background-repeat: no-repeat;
- /* background-position: right 0; */
- /* background-position: right bottom; */
- /* background-position: center center; */
- /* background-position: center; */
- /* background-position: 50px 0; */
- /* background-position: 50px 100px; */
- background-position: -50px -100px;
-
- /* 正数: 向右向下移动; 负数:向左向上移动 */
- /* 注意: 背景色和背景图只显示在盒子里面 */
- }
- </style>
- </head>
- <body>
- <div>文字</div>
- </body>
- </html>
-
- <!DOCTYPE html>
- <html lang="en">
- <head>
- <meta charset="UTF-8">
- <meta http-equiv="X-UA-Compatible" content="IE=edge">
- <meta name="viewport" content="width=device-width, initial-scale=1.0">
- <title>Document</title>
- <style>
- div {
- width: 400px;
- height: 400px;
- /* 不分先后顺序 背景色 背景图 背景图平铺 背景图位置 */
- /* background: pink url(./images/1.jpg) no-repeat center bottom; */
- /* 背景图位置如果是英文单词可以颠倒顺序 */
- background: pink url(./images/1.jpg) no-repeat bottom center ;
-
- /* 测试背景图位置如果是数值 不要颠倒顺序 */
- /* 水平50px, 垂直100px */
- /* background: pink url(./images/1.jpg) no-repeat 50px 100px; */
- background: pink url(./images/1.jpg) no-repeat 100px 50px;
-
-
- }
- </style>
- </head>
- <body>
- <div></div>
- </body>
- </html>
-
img标签和背景图片的区别
- <!DOCTYPE html>
- <html lang="en">
- <head>
- <meta charset="UTF-8">
- <meta http-equiv="X-UA-Compatible" content="IE=edge">
- <meta name="viewport" content="width=device-width, initial-scale=1.0">
- <title>Document</title>
- <style>
- /* 块: 独占一行; 宽度默认是父级100%; 添加宽度都生效 */
- div {
- width: 300px;
- height: 300px;
- background-color: pink;
-
- /* 块 换行*/
- display: block;
-
- /* 行内块 可以设置宽高*/
- /* display: inline-block; */
-
- /* 行内 不可以设置宽高*/
- /* display: inline; */
- }
- </style>
- </head>
- <body>
- <div>11111</div>
- <div>22222</div>
- </body>
- </html>
-
- <!DOCTYPE html>
- <html lang="en">
- <head>
- <meta charset="UTF-8">
- <meta http-equiv="X-UA-Compatible" content="IE=edge">
- <meta name="viewport" content="width=device-width, initial-scale=1.0">
- <title>Document</title>
- <style>
- /* 行内: 不换行; 设置宽高不生效; 尺寸和内容的大小相同 */
- span {
- width: 300px;
- height: 300px;
- background-color: pink;
-
- /* 行内块 不换行*/
- /* display: inline-block; */
-
- /* 块 换行*/
- /* display: block;*/
-
- /* 行内 不可以设置宽高*/
- display: inline;
- }
- </style>
- </head>
- <body>
- <span>span</span>
- <span>span</span>
- </body>
- </html>
-
- <!DOCTYPE html>
- <html lang="en">
- <head>
- <meta charset="UTF-8">
- <meta http-equiv="X-UA-Compatible" content="IE=edge">
- <meta name="viewport" content="width=device-width, initial-scale=1.0">
- <title>Document</title>
- <style>
- /* 行内: 不换行; 设置宽高不生效; 尺寸和内容的大小相同 */
- span {
- width: 300px;
- height: 300px;
- background-color: pink;
-
- /* 行内块 不换行*/
- /* display: inline-block; */
-
- /* 块 换行*/
- /* display: block;*/
-
- /* 行内 不可以设置宽高*/
- display: inline;
- }
- </style>
- </head>
- <body>
- <span>span</span>
- <span>span</span>
- </body>
- </html>
-
- <!DOCTYPE html>
- <html lang="en">
- <head>
- <meta charset="UTF-8">
- <meta http-equiv="X-UA-Compatible" content="IE=edge">
- <meta name="viewport" content="width=device-width, initial-scale=1.0">
- <title>Document</title>
- <style>
- /* 行内块: 一行显示多个; 加宽高生效 */
- img {
- width: 100px;
- height: 100px;
- }
- </style>
- </head>
- <body>
- <img src="./images/1.jpg" alt="">
- <img src="./images/1.jpg" alt="">
- </body>
- </html>
-
- <!DOCTYPE html>
- <html lang="en">
- <head>
- <meta charset="UTF-8">
- <meta http-equiv="X-UA-Compatible" content="IE=edge">
- <meta name="viewport" content="width=device-width, initial-scale=1.0">
- <title>Document</title>
- <style>
- div {
- color: red;
- font-size: 30px;
- height: 300px;
- }
- </style>
- </head>
- <body>
- <div>
- 这是div标签里面的文字
- <span>这是div里面的span</span>
- </div>
- </body>
- </html>
-
➢ 有哪些常见属性可以继承?
- color
- font-style、font-weight、font-size、font-family
- text-indent、text-align
- line-height
继承的应用
好处:可以在一定程度上减少代码
➢ 常见应用场景:
- 可以直接给ul设置 list-style:none 属性,从而去除列表默认的小圆点样式
- 直接给body标签设置统一的font-size,从而统一不同浏览器默认文字大小
继承失效的特殊情况
- <!DOCTYPE html>
- <html lang="en">
- <head>
- <meta charset="UTF-8">
- <meta http-equiv="X-UA-Compatible" content="IE=edge">
- <meta name="viewport" content="width=device-width, initial-scale=1.0">
- <title>Document</title>
- <style>
- div {
- color: red;
- color: green;
- }
-
- .box {
- font-size: 30px;
- }
- </style>
- </head>
- <body>
- <div class="box">文字</div>
- </body>
- </html>
-
- <!DOCTYPE html>
- <html lang="en">
- <head>
- <meta charset="UTF-8">
- <meta http-equiv="X-UA-Compatible" content="IE=edge">
- <meta name="viewport" content="width=device-width, initial-scale=1.0">
- <title>Document</title>
- <style>
- /* a 显示模式是行内, 加宽高默认不生效, 转显示模式: 行内块 */
- /*text-decoration:
- none 默认。定义标准的文本。
- underline 定义文本下的一条线。
- overline 定义文本上的一条线。
- line-through 定义穿过文本下的一条线。
- blink 定义闪烁的文本。
- inherit 规定应该从父元素继承
- text-decoration 属性的值。*/
- a {
- text-decoration: none; /*设置文本样式。*/
- width: 100px;
- height: 50px;
- background-color: red;
- display: inline-block;
- color: #fff;
- text-align: center;
- line-height: 50px;
- }
-
- a:hover {
- background-color: orange;
- }
- </style>
- </head>
- <body>
- <!-- a*5 -->
- <!-- 选多行加内容删除 alt + shift + 鼠标左键单击 -->
- <a href="#">导航1</a>
- <a href="#">导航2</a>
- <a href="#">导航3</a>
- <a href="#">导航4</a>
- <a href="#">导航5</a>
- </body>
- </html>
-
- <!DOCTYPE html>
- <html lang="en">
- <head>
- <meta charset="UTF-8">
- <meta http-equiv="X-UA-Compatible" content="IE=edge">
- <meta name="viewport" content="width=device-width, initial-scale=1.0">
- <title>Document</title>
- <style>
- a {
- text-decoration: none;
- width: 120px;
- height: 58px;
- background-color: pink;
- display: inline-block;
- text-align: center;
- line-height: 50px;
- color: #fff;
- }
- /* 每个a的背景图不同, 单独找到每个a, 设置不同的背景图片 */
- .one {
- background-image: url(./images/bg1.png);
- }
-
- .two {
- background-image: url(./images/bg2.png);
- }
-
- .three {
- background-image: url(./images/bg3.png);
- }
-
- .four {
- background-image: url(./images/bg4.png);
- }
-
- .one:hover {
- background-image: url(./images/bg5.png);
- }
-
- .two:hover {
- background-image: url(./images/bg6.png);
- }
-
- .three:hover {
- background-image: url(./images/bg7.png);
- }
-
- .four:hover {
- background-image: url(./images/bg8.png);
- }
- </style>
- </head>
- <body>
- <a href="#" class="one">五彩导航</a>
- <a href="#" class="two">五彩导航</a>
- <a href="#" class="three">五彩导航</a>
- <a href="#" class="four">五彩导航</a>
- </body>
- </html>
-