代碼哪里有錯？？？為什么都沒有效果？
<!DOCTYPE html>
<html>
<head>
<title>制作</title>
<style type="text/css">
body{margin:0;padding:0;color:#66c;}
.demo1{width:800px;position: relative;}
.demo1.left: {width:300px;float:left;}
?.demo1.left img{margin-left: 20px;}
?.demo1.right{width:458px;padding:20px; float:right;background:#97c;border: 1px solid #ccc}
?.demo1.right p{font-size: 15px;line-height: 20px;}
?.demo1 span{position:absolute;right: 20px;top:10px;font-size:12px; }
</style>
</head>
<body>
<div class="demo1">
<div class="left">
<img src="http://img2.woyaogexing.com/2017/09/24/d76786da97e3acf6!200x200.jpg">
</div>
<div class="right">
<h6>廢物</h6>
<p>而是吃這個的時候人與人之間好溝通，吃小龍蝦得兩個手，就不用玩手機了</p>
<span>10分鐘之前</span>
</div>
</div>
</body>
</html>
2018-06-19
確實是沒空格,要寫成demo1 . right
demo1 .left 這樣
2018-06-10
會不會是 .demo1后面沒有空格