How to create a simple calculator using HTML-CSS.

Creating a simple calculator on your own is a good basic thing.

This is a simple calculator -HTML-CSS code:

HTML code:
                                		
 <form>
 <table id="table">
            <tr>
                <td id="td">Enter First Number
                <td colspan="1">
 
                    <input name="firstnumber" type="number" />
            <tr>
                <td id="td1">Select Operator
                <td>
                    <select id="select" name="operator"/>
<option>+</option>
<option>-</option>
<option>*</option>
<option>/</option>

               
            <tr>
                <td id="td">Enter Second Number
                <td class="auto-style5">
                    <input name="secondnumber" type="number"  />
 
            
            <tr>
                <td>
                <td><input type="submit" name="calculate" value="Calculate" id="td3" />
 
            
            <tr>
                <td id="td2">Output = 
                <td>
 
            
       </table>
 </form>
 
CSS code;
#table {
	float: right;
	margin-right: 40%;
	outline: double;
}

#td {

	background-color:#FF66FF;
	color:#000;
	font-family:'Times New Roman';

}
#select {
	width: 63px;

}
#td1 {

	background-color:#3399FF;
	color:#000;
	font-family:'Times New Roman';

}
#td2 {

	background-color:#9999FF;
	color:#000;
	font-family:'Times New Roman';

}
#td3 {
	background-color:#0099FF;
	color:wheat;

	

}