.login_user_button {
   cursor:pointer;
   width:32px;
   height:32px;
   background: url(../images/cms_login.png) no-repeat;
}

.login_user_button:hover {
   background: url('../images/cms_login_o.png') no-repeat;
}

.logout_user_button {
   cursor:pointer;
   width:32px;
   height:32px;
   background: url(../images/cms_logout.png) no-repeat;
}

.logout_user_button:hover {
   background: url('../images/cms_logout_o.png') no-repeat;
}