<?php
$content = file_get_contents('index.php');
$open = substr_count($content, '<div');
$close = substr_count($content, '</div');
echo "Open: $open, Close: $close\n";

// Trace where it goes wrong
$lines = explode("\n", $content);
$depth = 0;
foreach ($lines as $i => $line) {
    $line_open = substr_count($line, '<div');
    $line_close = substr_count($line, '</div');
    $old_depth = $depth;
    $depth += $line_open - $line_close;
    if (($i + 1) >= 760 && ($i + 1) <= 780) {
        echo "Line " . ($i + 1) . ": Depth $old_depth -> $depth | " . trim($line) . "\n";
    }
}
echo "Final depth: $depth\n";