Highlight search terms in Wordpress

function search_excerpt_highlight()
{
    $content = get_the_content();
    $content = wp_strip_all_tags($content);

    // Set the excerpt length
    $excerpt_length = 100; // You can adjust this value to your desired excerpt length
    $padding = 10; // Add padding around the search term

    $keys = explode(' ', get_search_query());
    $first_key = $keys[0];

    // Find the first occurrence of the search term
    $term_pos = stripos($content, $first_key);

    if ($term_pos !== false) {
        $start = max(0, $term_pos - $padding);
        $prefix = $start > 0 ? '...' : ''; // Add "..." prefix if the excerpt doesn't start from the beginning
        $excerpt = mb_strimwidth($content, $start, $excerpt_length, '...');
        $excerpt = $prefix . $excerpt;
    } else {
        // If the search term is not found, use the original content with a trimmed excerpt
        $excerpt = mb_strimwidth($content, 0, $excerpt_length, '...');
    }

    // Highlight the search terms
    $pattern = '/(' . implode('|', $keys) . ')/iu';
    $excerpt = preg_replace($pattern, '<span class="highlighted">\0</span>', $excerpt);

    return $excerpt;
}