test.js

;(function($) {
   $.fn.fixMe = function() {
      return this.each(function() {
         var $this = $(this),
            $t_fixed;
         function init() {
            $this.wrap('<div class="container" />');
            $t_fixed = $this.clone();
            $t_fixed.find("tbody").remove().end().addClass("fixed").insertBefore($this);
            resizeFixed();
         }
         function resizeFixed() {
            $t_fixed.find("th").each(function(index) {
               $(this).css("width",$this.find("th").eq(index).outerWidth()+"px");
            });
         }
         function scrollFixed() {
            var offset = $(this).scrollTop(),
            tableOffsetTop = $this.offset().top,
            tableOffsetBottom = tableOffsetTop + $this.height() - $this.find("thead").height();
            if(offset < tableOffsetTop || offset > tableOffsetBottom)
               $t_fixed.hide();
            else if(offset >= tableOffsetTop && offset <= tableOffsetBottom && $t_fixed.is(":hidden"))
               $t_fixed.show();
         }
         $(window).resize(resizeFixed);
         $(window).scroll(scrollFixed);
         init();
      });
   };
})(jQuery);
/*
$(document).ready(function(){
   $("table").fixMe();
   $(".up").click(function() {
      $('html, body').animate({
      scrollTop: 0
   }, 2000); 
 });*/
});

body{
font:12px normal Arial,sans-serif;
color:#000;
}

h1{
text-align:center;
text-transform:uppercase;
letter-spacing:-2px;
font-size:2.5em;
margin:20px 0;
}

.container{
width:90%;
margin:auto;
}

table{
border-collapse:collapse;
width:100%;
}

.blue{
/* border:2px solid red; */
}

.blue thead{
background:red;
}

.purple{
border:2px solid #9B59B6;
}

.purple thead{
background:#9B59B6;
}

thead{
color:white;
}

th,td{
text-align:center;
padding:2px 0;
}

tbody tr:nth-child(even){
background:red;
color:white;
}

tbody tr:hover{
background:#BDC3C7;
color:#FFFFFF;
}

.fixed{
top:0;
position:fixed;
width:auto;
display:none;
border:none;
}

.scrollMore{
margin-top:600px;
}

.up{
cursor:pointer;
}