.content {
   width:100%;
}

#skbcontent {
   margin-left: 305px;
   margin-right: 15px;
   position: relative;
   vertical-align: top;
}

.toc {
   background-color: whitesmoke;
   border: 2px solid gainsboro;
   position: fixed;
   overflow: auto;
   vertical-align: top;
   white-space: nowrap;
   width: 295px;
}
 
.toc ul li {
   margin: 0;
   list-style: none;
   background-position: 5px 0px;
   padding-left: 25px;
   background-repeat: no-repeat;
   background-image: url(topic.gif);
}

.toc ul, .toc li {
    list-style: none;
    margin: 0;
    padding: 0;
    overflow: visible;
    width: 100%;
}

.toc a {
   display: inline-block;
   margin-bottom: 3px;
   text-decoration: none;
   width: 100%;
}

.toc a:hover {
   background-color: skyblue;
}

.toc a.selected {
   background-color: gold;
}

/* Collapsed state for list element */
.toc .collapsed {
    background-image: url(cbook.gif);
}
/* Expanded state for list element */
/* NOTE: This class must be located AFTER the collapsed one */
.toc .expanded {
    background-image: url(obook.gif);
}

.tocmenu {
   background-color: white;
   border:2px solid silver;
   border-radius: 5px;
   box-shadow: 10px 10px 5px #888888;
   color: white;
   display: none;
   position: absolute;
   width: 150px;
}

.tocmenu ul, .tocmenu li {
   list-style: none;
   margin: 0;
   padding: 0;
   overflow: visible;
   width: 100%;
}

.tocmenu img {
   margin: 0 5px;
}

.tocmenu a {
   color: dimgray;
   display: inline-block;
   text-decoration: none;
   width: 100%;
}

.tocmenu a:hover {
   background-color: gray;
   color: white;
}

.popup_overlay {
   background: rgba( 0, 0, 0, 0.6 );
   display:none;
   position: absolute;
   top: 0%;
   left: 0%;
   width: 100%;
   height: 100%;
   z-index:1001;
   text-align: center;
}

.popup_content {
   background-color: white;
   border:2px solid gray;
   border-radius: 5px;
   display: block;
   margin: auto;
   position: fixed;
   top: 50%;
   left: 50%;
   margin-left: -90px;
   margin-top: -55px;
   width: 180px;
   height: 110px;
   padding: 5px;
   z-index:1002;
   overflow: auto;
}