为什么没有任何效果？
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<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>我们互动下</title>
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var content=prompt("输入JS进阶篇");
if(content=="JS进阶篇"){
alert("关注JS高级篇");
}
</script>
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<body>
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