Figured it out. The developer who made my theme was loading jQuery in the footer, not through WordPress’s enqueue scripts function. For those who find this, try adding this to your functions.php file:
function include_custom_jquery() {
wp_deregister_script('jquery');
wp_enqueue_script('jquery', 'https://ajax.googleapis.com/ajax/libs/jquery/3.0.0/jquery.min.js', array(), null, true);
}
add_action('wp_enqueue_scripts', 'include_custom_jquery');