Help me! body Tag callbacks not work

[romy2012]

body,html{height: 100%;}

$("body").mCustomScrollbar({ theme:"minimal-dark", scrollButtons:{ enable:true }, callbacks:{ onScrollStart:function(){ myCallback(this,"#onScrollStart") }, onScroll:function(){ myCallback(this,"#onScroll") }, onTotalScroll:function(){ myCallback(this,"#onTotalScroll") }, onTotalScrollOffset:60, onTotalScrollBack:function(){ myCallback(this,"#onTotalScrollBack") }, onTotalScrollBackOffset:50, whileScrolling:function(){ console.log('xxxxx') }, alwaysTriggerOffsets:false } });