Smooth scrolling lors des ancres internes

scroll.js

/**!
 * Smoothscrolling to an id
 *
 * @contributors: Damien Senger (Alsacréations)
 * @date-created: 2015-07-20
 * @last-update: 2015-07-20
 * */

(function($) {
  $(document).ready(function() {
    $('a[href^="#"]').click(function() {
      // when we click on an element
      var width = $('body').width(),
        target = $(this).attr('href');


      if ($(target).length && target != "#") {
        var position = $(target).offset().top,
          decalage = 200,
          destination = position - decalage,
          speed = 750; // Animation duration in ms

        // we move to the destination
        $('html, body').animate({
          scrollTop: destination,
        }, speed);
      }

      // we cancel the click on this link
      return false;
    });
  });
}(jQuery));