如何用PHP根据数值动态修改HTML TD背景色？附解决代码

我尝试用PHP根据数值动态修改HTML <td> 的背景色，但代码一直无法正常运行，为此感到困扰。以下是我最初的代码：

<td data-column="% Over 0.5 SH" style="background-color: <?php echo $backgroundColorOver05SH; ?>">
<?php 
if (($row['TotalMatch']) > 9){ 
$percover05sh = $row['OK_05sh'] / $row['TotalMatch'] * 100; 
echo sprintf("%.2f", $percover05sh);

if ($percover05sh > 80){
    $backgroundColorOver05SH = "green";
} elseif ($percover05sh >= 70 and $percover05sh <= 79.99  ){
    $backgroundColorOver05SH = "yellow";
} else {
    $backgroundColorOver05SH = "red";
}

我认为思路是对的，但找不到正确的解决方案，希望能得到建议！

更新： 代码现已正常运行，以下是完整代码：

<?php 
if (($row['TotalMatch']) > 9){ 
$percover05sh = $row['OK_05sh'] / $row['TotalMatch'] * 100; 

if ($percover05sh >= 80){
    $backgroundColorOver05SH = "green";
} elseif ($percover05sh >= 70 && $percover05sh < 80  ){
    $backgroundColorOver05SH = "yellow";
} else {
    $backgroundColorOver05SH = "red";
}

}else{
echo 'No Bet';
}     ?>
<td data-column="% Over 0.5 SH" style="background-color: <?php echo $backgroundColorOver05SH;?>;">
<?php
echo sprintf("%.2f", $percover05sh);    
?>
</td>

内容的提问来源于stack exchange，提问作者marcello gabrielli