<?php
$html = file_get_contents('full_page.html');
$pos = strpos($html, 'content-between px-3 box-product-details');
if ($pos !== false) {
    $start = max(0, $pos - 1000);
    echo substr($html, $start, 1200);
} else {
    echo "Pattern not found\n";
    // Find another marker
    $pos = strpos($html, 'box-product-details');
    if ($pos !== false) {
        $start = max(0, $pos - 1000);
        echo "At box-product-details:\n" . substr($html, $start, 1200);
    }
}
