Untitled

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>First Steps Into PHP</title>
	<style>
		table * {
			border: 1px solid black;
			width: 50px;
			height: 50px;
		}
    </style>
</head>
<body>
<table>
    <tr>
        <td>
            Red
        </td>
        <td>
            Green
        </td>
        <td>
            Blue
        </td>
    </tr>
<?php
$color = 51;
for ($i = 0; $i<5; $i++, $color+=51){ ?>
    <tr>
        <td style="background: rgb(<?= $color ?>, 0, 0);"></td>
        <td style="background: rgb(0, <?= $color ?>, 0);"></td>
        <td style="background: rgb(0, 0, <?= $color ?>);"></td>
    </tr>
<?php } ?>
</table>
</body>
</html>