console 命令行工具 X clear

console

	function order(){
				//定义
				var hb =parseInt(document.getElementById("hb").value) ;
				var fr =parseInt(document.getElementById("fr").value) ;
				var cola =parseInt(document.getElementById("cola").value) ;
				
				//计算
				var result = Math.floor(3.55*hb + 1.88*fr + 0.75*cola);
				
				//输出
				document.getElementById("total").value=result;
				
			}

	<body>
		<div class="top" style="height:70px;border-bottom:1px solid #ddd;">
<img class="logoIndex" height="60" src="https://www.zenitour.com/img/logoIndex.png" style="margin-left:10px;margin-top:5px;">
</div>
		<div class="content" style="text-align:center;margin-top:50px;height: 78%;">
		<label >Hamburger&nbsp;&nbsp;$3.55</label>
		<input type="text" id="hb" /><br />
		<label >&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Fries $1.88&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</label>
		<input type="text" id="fr" /><br />
		<label >Coca Cola   $0.75&nbsp;&nbsp;&nbsp;</label>
		<input type="text" id="cola"  /><br />
		<p style="margin-left:10%;"><button type="button" onclick="order()">Order</button></p>
		<label style="margin-left:5%;">Tatal</label>
		<input type="text" id="total" /><br />
		</div>
<div id="bottom" style="text-align:center;border-top:1px solid #ddd;">
<span class="centerspan" style="font-size:10px">Copyright © 2017 Zenitour lnc All Rights Reserved　版权所有-哲途教育  渝ICP备13002955号-2</span>
</div>
	</body>

         html,body {
            width: 100%;
            height: 100%;
            margin: 0;
            padding: 0;
        }