HTML设置滚动字幕

<marquee behavior="alternate">来回滚动</marquee>   
  
<marquee behavior="scroll">单方向循环滚动</marquee>   
  
<marquee behavior="scroll" direction="up" height="30">改单方向向上循环滚动</marquee>   
  
<marquee behavior="slide">只滚动一次</marquee>   
  
<marquee behavior="slide" direction="up">改向上只滚动一次了</marquee>   
  
<marquee behavior=="slide" direction="left" bgcolor="red">背景色是红色的</marquee>  
  
<marquee direction="right">我向右滚动</marquee>   
  
<marquee direction="down">向下滚动</marquee>