JavaScript实现鼠标移入随机变换颜色

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		<style>
			/* 这里定义一下div（块元素）已下span 标签的宽.高.边框线以及边框线的颜色*/
			span{
				display: block;
				width: 80px;
				height: 80px;
				border: 1px solid #000000;
				float: left;
			}
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		</div>
		<script type="text/javascript">
			var a=document.getElementsByTagName("span");
			/* 获取一下span标签 */
				for(var i=0;i<=a.length;i++){
					a[i].onmouseover=function(){
						/* 循环出每一个方块，加入鼠标移入 */
						this.style.backgroundColor="#"+Math.floor(Math.random()*16777215).toString(16);
						/* 颜色随机颜色 */
					}
				}
		</script>
	</body>
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