.index #btn2_acc {background-image:url('img/btn_acc.png');}
.index #btn2_lin {background-image:url('img/btn_lin.png');}
.index #btn2_oeu {background-image:url('img/btn_oeu.png');}
.index #btn2_exp {background-image:url('img/btn_exp.png');}
.index #btn2_con {background-image:url('img/btn_con.png');}
#btn2_acc {background-image:url('img/btn_acc2.png');}
#btn2_lin {background-image:url('img/btn_lin2.png');}
#btn2_oeu {background-image:url('img/btn_oeu2.png');}
#btn2_exp {background-image:url('img/btn_exp2.png');}
#btn2_con {background-image:url('img/btn_con2.png');}