第1个回答 推荐于2016-03-15
<style>
.aa{background-color:#ff9966;width:200;color:green;}
</style>
<span type="button" class="aa" id="sp1">关于改变CSS</span><br>
<INPUT TYPE="button" onclick="document.styleSheets[0].rules[0].style.color='red'" value="红色">
<INPUT TYPE="button" onclick="document.styleSheets[0].rules[0].style.color='blue'" value="蓝色">
<INPUT TYPE="button" onclick="document.styleSheets[0].rules[0].style.width='300'" value="300">
<INPUT TYPE="button" onclick="document.styleSheets[0].rules[0].style.width='400'" value="400">
<INPUT TYPE="button" onclick="document.styleSheets[0].rules[0].style.backgroundColor='#E066FF'" value="背景紫色">
<INPUT TYPE="button" onclick="document.styleSheets[0].rules[0].style.backgroundColor='#F4A460'" value="背景黄色">本回答被提问者采纳