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/**
 * Smooth Anchor Links
 *
 * This works with the anchor links in the URL too. It also changes the 
 * URL hash 
 *
 * Replace .offset_element_selector with the offset element, e.g., .navbar
 */
jQuery(document).ready(function($) {

  var hash         = window.location.hash,
      $offsetEl   = $('.offset_element_selector'),
      $links      = $('a[href^="#"]'),
      $wpadminbar = $('#wpadminbar');

  // Check if URL has hash and smooth scroll to that. 
  if ( hash ) {
    var $hashEl = $(hash);
    if ( $hashEl.length ) {
      scrollToAnchor( $hashEl );
      $(window).load(function() {
        scrollToAnchor( $hashEl );
      });
    }
  }

  $links.on('click', function(e) {
    var $this  = $(this),
        thisHref    = $this.attr('href');

    if ( thisHref !== '#' ) {
      if ( $(thisHref).length ) {
        e.preventDefault();
        scrollToAnchor( $(thisHref) );
      }
    }
  });

  function scrollToAnchor( $el ) {
    offset = $offsetEl.outerHeight() + $wpadminbar.outerHeight();
    $('html, body').animate({
      scrollTop: $el.offset().top - offset
    }, 500);
  }
});