What best practices should be followed when creating a countdown timer in PHP that counts down from a specific time without date information?

When creating a countdown timer in PHP that counts down from a specific time without date information, it is important to calculate the remaining time in seconds and then convert it to hours, minutes, and seconds for display. To achieve this, you can use the PHP functions time() to get the current time and strtotime() to convert the specific time to a timestamp. By subtracting the two timestamps and formatting the remaining time, you can create a countdown timer that accurately displays the time remaining.

$specific_time = strtotime('15:30:00'); // Specific time to count down from
$current_time = time(); // Current time
$remaining_time = $specific_time - $current_time; // Calculate remaining time in seconds

$hours = floor($remaining_time / 3600);
$minutes = floor(($remaining_time % 3600) / 60);
$seconds = $remaining_time % 60;

echo "Time remaining: " . $hours . " hours, " . $minutes . " minutes, " . $seconds . " seconds";