document.addEventListener('DOMContentLoaded', function () { const urlParams = new URLSearchParams(window.location.search); // Ensure elements exist before trying to set values const utmSourceElement = document.getElementById('utm_source'); const utmMediumElement = document.getElementById('utm_medium'); const utmCampaignElement = document.getElementById('utm_campaign'); if (utmSourceElement) { utmSourceElement.value = urlParams.get('utm_source') || ''; } if (utmMediumElement) { utmMediumElement.value = urlParams.get('utm_medium') || ''; } if (utmCampaignElement) { utmCampaignElement.value = urlParams.get('utm_campaign') || ''; } // Add other UTM parameters if necessary, following the same pattern });