l-hammer/YDTemplate

/**
 * Created by LHammer on 18/03/07.
 * ES5 version
 * @function scrollToTop 返回顶部
 */

var $ = 'jquery',
  scrollToTop;

scrollToTop = function () {
  $(window).scrollTop() === 0 ? null : ($('html, body').stop(true).animate({
    scrollTop: 0,
  }, 600));
};
// 滚动时高亮指定悬浮导航
$(window).scroll(function () {
  var i,
    d = 589,
    wst = $(window).scrollTop(),
    wstmid = wst + ($(window).height() / 2);
  if (wst > d) {
    $('.float_menu').fadeIn();
  } else {
    $('.float_menu').fadeOut();
  }
  for (i = 2; i < 5; i++) {
    if ($('#floor' + i).offset().top <= wstmid) {
      $('.menu_item').removeClass('active');
      $('a[href="#floor' + i + '"]').addClass('active');
    }
  }
});

/**
 * e.g.
 */
scrollToTop();