現在每個網站都很流行的鎖定選單列語法

HTML

 

menu

">Menu goes here - home - links - blah blah

CSS

.menu {background:#00a; color:#fff; height:40px; line-height:40px;letter-spacing:1px; width:100%;}

SCRIPT

// Create a clone of the menu, right next to original.
$('.menu').addClass('original').clone().insertAfter('.menu').addClass('cloned').css('position','fixed').css('top','0').css('margin-top','0').css('z-index','500').removeClass('original').hide();

scrollIntervalID = setInterval(stickIt, 10);


function stickIt() {

  var orgElementPos = $('.original').offset();
  orgElementTop = orgElementPos.top;              

  if ($(window).scrollTop() >= (orgElementTop)) {
    // scrolled past the original position; now only show the cloned, sticky element.

    // Cloned element should always have same left position and width as original element.    
    orgElement = $('.original');
    coordsOrgElement = orgElement.offset();
    leftOrgElement = coordsOrgElement.left;
    widthOrgElement = orgElement.css('width');
    $('.cloned').css('left',leftOrgElement+'px').css('top',0).css('width',widthOrgElement).show();
    $('.original').css('visibility','hidden');
  } else {
    // not scrolled past the menu; only show the original menu.
    $('.cloned').hide();
    $('.original').css('visibility','visible');
  }
}


參考資料來源：
http://codepen.io/senff/pen/ayGvD