Calculator 2 in HTML , CSS

<html>
<head>
<title>Calculator</title>
<script></script>
<style>
#d1{
position:absolute;
top:25%;
left:25%;
margin:auto;
text-align:center;
background-color:#9DCBEE;
box-shadow: 10px 10px 5px #C8D8DF;}
</style>
</head>
<body style="background:#DDEEFF">
<div align="center" id="d1">
<table>
<tr>
<td colspan="3"><input type="text" width="100%"/></td>
</tr>
<tr>
<td><input type="button" value="C" style="width:100%"/></td>
<td><input type="button" value="+" style="width:100%"/></td>
<td><input type="button" value="=" style="width:100%"/></td>
</tr>
<tr>
<td><input type="button" value="-" style="width:100%"/></td>
<td><input type="button" value="*" style="width:100%"/></td>
<td><input type="button" value="/" style="width:100%"/></td>
</tr>
<tr>
<td><input type="button" value="1" style="width:100%"/></td>
<td><input type="button" value="2" style="width:100%"/></td>
<td><input type="button" value="3" style="width:100%"/></td>
</tr>
<tr>
<td><input type="button" value="4" style="width:100%"/></td>
<td><input type="button" value="5" style="width:100%"/></td>
<td><input type="button" value="6" style="width:100%"/></td>
</tr>
<tr>
<td><input type="button" value="7" style="width:100%"/></td>
<td><input type="button" value="8" style="width:100%"/></td>
<td><input type="button" value="9" style="width:100%"/></td>
</tr>
<tr>
<td><br/></td>
<td><input type="button" value="0" style="width:100%"/></td>
<td><br/></td>
</tr>
</table>
</div>
</body>