var Box = {      
  roundTop: function(element, fgcolor, bgcolor, size, style) {   
    size = size || 4;
    style = style || "r";
    var dummy = document.createElement("b");
    dummy.className = style + "top";
    dummy.style.backgroundColor = bgcolor;
    for(var i=1; i<=size; i++) {
      var dummy_child=document.createElement("b");
      dummy_child.className= style + i;
      dummy_child.style.backgroundColor = fgcolor;
      dummy.appendChild(dummy_child);
    }       
    $(element).insertBefore(dummy, $(element).firstChild);
  },             
    
  roundBottom: function(element, fgcolor, bgcolor, size, style) {
    size = size || 4;
    style = style || "r";
    var dummy = document.createElement("b");
    dummy.className = style + "bottom";
    dummy.style.backgroundColor = bgcolor;
    for(var i=size; i > 0; i--) {
      var dummy_child=document.createElement("b");
      dummy_child.className= style + i;
      dummy_child.style.backgroundColor = fgcolor;
      dummy.appendChild(dummy_child);
    }       
    $(element).appendChild(dummy, $(element).firstChild); 
  },                 
                                           
  round: function(element, fgcolor, bgcolor, size, style) {
    Box.roundTop(element, fgcolor, bgcolor, size, style);                       
    Box.roundBottom(element, fgcolor, bgcolor, size, style);
  }
};