.sub     {display:none; }
.subexp  {display:block;}
li.exp   {list-style-image:url("plus.png");}
li.col   {list-style-image:url("minus.png");}
li.basic {list-style:square;}
ol.subexp li {list-style:decimal;}

li.exp_active {list-style-image:url("plus.png");color:blue}
li.col_active {list-style-image:url("minus.png");color:red}
li.basic_active {list-style:square;color:green}