BMI calculator

<?php include 'header.php'; ?>

<script language="JavaScript">
<!--
function calculateBmi() {
var weight = document.bmiForm.weight.value
var height = document.bmiForm.height.value
if(weight > 0 && height > 0){
var finalBmi = weight/(height/100*height/100)
document.bmiForm.bmi.value = finalBmi
if(finalBmi < 18.5){
document.bmiForm.meaning.value = "You are too thin."
}
if(finalBmi > 18.5 && finalBmi < 25){
document.bmiForm.meaning.value = "Your are healthy."
}
if(finalBmi > 25){
document.bmiForm.meaning.value = "You have overweight."
}
}
else{
alert("Please Fill in everything correctly")
}
}
//-->
</script>
<style>
td {
	height:20px;
}
</style>
<?php if(!isset($_SESSION['u_name']) && empty($_SESSION['u_name'])){

echo '<div class="bigbox">
	<div class="heading" style="margin-top:50px;">Sorry ! you are not logged in. | Login to view this Page</div>
	<hr></div>';
}else {

	echo'
<div class="bigbox">
	<div class="heading" style="margin-top:50px;">Calculate Your Body Mass Index (BMI) | Calculator is Below</div>
	<hr>
<table border="0" style="width:650px;margin:0 auto;border:2px solid #F25822;
border-radius:5px;padding-top:15px;padding-left:5px;padding-bottom:15px;padding-right:5px;box-shadow:0px 0px 5px 5px grey;margin-top:40px;">
<tr>
	<form name="bmiForm">
		<td>Your Weight(kg):</td><td><input type="text" name="weight" placeholder="Your Weight (Kg)"></td>

		<td>Your Height(cm): </td><td><input type="text" name="height" placeholder="Your Height (CM)"></td></tr>
		<tr><td colspan="4"><hr style="display:none;"></td></tr>
		<tr><td colspan="4" align="right"><input type="button" value="Calculate BMI" style="width:200px;margin-right:30px;" onClick="calculateBmi()" class="button"></td></tr>
		<tr><td colspan="4"><hr ></td></tr>
		<tr><td>Your BMI:</td><td colspan="3"><input type="text" readonly style="border:none;font-weight:bold;" size="65" name="bmi" placeholder="Your BMI Calculations will show here"></td></tr>
		<tr><td>Remarks: </td><td colspan="3"><input type="text" readonly style="border:none;font-weight:bold;" size="65" name="meaning" placeholder="Remarks"></td></tr>
		<tr><td colspan="4"><hr style="display:none;"></td></tr>
		<tr><td colspan="4" align="right"><input type="reset" value="Reset" style="width:200px;margin-right:30px;" class="button" /></td></tr>
	</form>
	</table>
</div>';}

?>
<?php include 'footer.php'; ?>