关于左右浮动依照relative父元素的基线是什么?是父元素的content,还是border?
我的right_span标签让它靠右,但必须要设置right:5px;效果如下:
要是设置right:0px;就会顶到border。
再者:为什么我的left_span设置为left:0px;,它却紧贴着content内容呢?
<!doctype html>
<html>
<head>
<meta charset="utf-8">
<title></title>
<meta name="viewport" content="width=device-width,initial-scale=1,minimum-scale=1,maximum-scale=1,user-scalable=no" />
<link href="css/mui.css" rel="stylesheet" />
<style>
*{
margin: 0px;
padding: 0px;
}
#box{
width: 500px;
height: 200px;
border: 1px solid #9ACD32;
padding: 5px;
margin: 100px auto;
position: relative;
}
#inner{
width: 500px;
height: 200px;
overflow: hidden;
position: relative;
}
#inner ul{
width: 3000px;/* 让其子元素进行浮动,必须给其空间 */
position: absolute;
list-style: none;
}
#inner ul li {
float: left;
}
#arr span{
width: 50px;
height: 50px;
background-color: #000000;
opacity: 0.3;
color: #F0F0F0;
font-size: 32px;
text-align: center;
position: absolute;
top: 50%;
margin-top: -20px;
}
/*=================重点在这================*/
#left{
left: 0px;
}
#right{
right: 0px;
left: auto;
}
</style>
</head>
<body>
<div id="box">
<div id="inner">
<ul>
<li><img src="img/1.jpg" alt=""></li>
<li><img src="img/1.jpg" alt=""></li>
</ul>
<ol>
</ol>
</div>
<div id="arr"><span id="left:"><</span><span id="right">></span></div>
</div>
<script type="text/javascript">
</script>
</body>
</html>
我本来是准备做轮播图的,用到这点html+css浮动问题,想知道形成这样的原理是什么?浮动元素左浮动、右浮动他们的依照的基线是父元素的什么?