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<h1 id="title">我是h1标题</h1>	    <script type="text/javascript">	    	// 1. 定义变量title	    	// 2. 获取到页面内的#title的元素节点=>title	    	// 3. 修改title的内容为“我已经被修改了。”	    	// 4. 修改title的字体颜色为红色	    		    	// 1. 定义变量title            // 2. 获取到页面内的#title的元素节点=>title	    	var title = document.querySelector("#title");	    		    	// 3. 修改title的内容为“我已经被修改了。”	    	title.innerHTML = "我已经被修改了。";	    		    	// 4. 修改title的字体颜色为红色	    	title.style.color = "red";	    </script>