为网页添加样式
术语解释
h1{
color: brown;
background-color: lightblue;
text-align: center;
}
css规则=选择器+声明块
选择器
选择器:选中元素h1
- ID选择器: 选中的是对应ID值的元素 #id名
- 元素选择器 h1
- 类选择器
<!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>
.red{
color: brown;
font-size: 2em;
background-color: lightblue;
text-align: center;
}
.big{
font-size: 3em;
text-align: center;
}
</style>
</head>
<body>
<h1 class="big red">
现在太难紧挨阳朔
</h1>
<p class="red">Lorem ipsum dolor sit amet consectetur adipisicing elit. Quam unde tempora necessitatibus reprehenderit, eius aliquid enim, veniam accusamus ab, nobis numquam non ullam cumque consectetur distinctio voluptate saepe! Modi, minus!</p>
<p>Molestias tenetur illo adipisci provident, hic at sequi assumenda odit, officia excepturi corporis accusamus culpa optio commodi laborum ipsa nemo cum voluptatem mollitia quasi. Quam dolore reiciendis adipisci architecto aut.</p>
<p>Atque facere unde ipsam, a numquam vero temporibus quas quae non doloremque iusto ut fuga neque sapiente distinctio expedita itaque cumque officiis. Pariatur minima amet culpa vero architecto sapiente quos!</p>
<p>Debitis, rem! Neque repudiandae molestias cupiditate quaerat voluptatem rem aliquid similique labore ducimus ex aut sapiente quo doloremque ut quidem deserunt, minima molestiae animi nam nihil error tempora? Hic, ullam?</p>
</body>
</html>
声明块
出现在{}内
声明块中包含很多声明(属性),每个声明表示一个样式规则
css代码书写位置
-
内部样式表
书写在style元素内(head)内,希望浏览器最先加载 -
内联样式表 元素样式
-
外部样式表(推荐)
写到独立的css文件中
好处:
3.1 解决多页面样式重复的问题
(Ctrl+点击——>新页面打开)
3.2 有利于浏览器缓存,提高页面响应速度
3.3 有利于代码分离(HTML和CSS),容易阅读和维护
css文件:
.red-big-center{
color: red;
font-size: 5em;
text-align: center;
}
HTML里用相对路径:
<!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>
<link rel="stylesheet" href="./inde.css">
</head>
<body>
<div class="red-big-center">
Lorem ipsum dolor sit amet.
</div>
</body>
</html>
link空元素 写在head里面, href里写相对路径