body { background:#fff; padding:50px;}

#dotgrid { margin:0px auto; position:relative; border:0px solid white; background:white; overflow: hidden}
#dotgrid .marker { width:2px; height:2px; background:#ccc; position:absolute; margin-top:-1px; margin-left:-1px; border-radius:4px; z-index:50;}
#dotgrid .marker.block { background:black; }
#dotgrid #cursor { width:6px; height:6px; background:red; margin-top:-3px; margin-left:-3px; position:absolute; z-index:25; border-radius:10px;}
#dotgrid #cursor_from { width:6px; height:6px; background:white; margin-top:-5px; margin-left:-5px; position:absolute; z-index:25; border-radius:10px; left:-100px;border:2px solid black;}
#dotgrid #cursor_to { width:6px; height:6px; background:white; margin-top:-5px; margin-left:-5px; position:absolute; z-index:25; border-radius:10px; left:-100px; border:2px solid black;}
input { padding:2px 5px; border-radius:20px; margin:0px auto; display:none;}
.vector { position:relative; z-index:900; }
pre { font-family:courier; font-size:11px; position:fixed; left:0px; bottom:20px;}