<!DOCTYPE html>
<html>
<head>
<style>
a:link{
color:red;
}
a:visited{
color:blue;
}
a:hover {
color: black;
}
a:active {
color: green;
}
</style>
</head>
<body>
<h1>This is a Heading</h1>
<p>This is a paragraph.</p>
<p><a href="http://www.w3schools.com">W3Schools.com</a></p>
</body>
</html>
请问为什么只有蓝 黑 绿 三种颜色能看到呢?
慕虎1618318
sdwsq
GavinZeng
fantacy吴贝
stone310