jquery animate实现slideup slidedown反向效果

function showLockWarningUI(selection_id){
    var element = $('#' + selection_id + ' .lock-warning-container');
    element.show().find('.lock-warning-section').css('opacity','0').animate({top:'0px',opacity:'1'},500);
    setTimeout(function(){
    hideLockingWarningUI(selection_id);
    },2000);
}
function hideLockingWarningUI(selection_id){
    var element = $('#' + selection_id + ' .lock-warning-container');
    element.find('.lock-warning-section').animate({top:'41px',opacity:'0'},500,function(){
    element.hide();
});
}