@media screen and max-width: 1000px {
    .sliding-menu { display:none; }
    .col-poster { display: none; }
}

* {
  box-sizing: border-box;
}

img {
    max-width: 100%;
}

.row::after {
    content: "";
    clear: both;
    display: block;
}

[class*="col-"] {
  width: 100%;
  float: left;
  padding: 10px;
  margin-top: 10px;
  margin-bottom: 10px;
  margin-left: 0px;
  margin-right: 0px;
}

.col-poster, .col-header {
    text-align:center;
    background-color: lightblue;
    padding: 10px;
    margin-bottom: 10px;
}

@media only screen and (min-width: 1000px) {
  /* For desktop: */
    .col-poster, .col-menu {width: 25%;}
    .col-header, .col-main, .col-footer {float: right; width: 74%; margin-left: 1%;}

div.col-menu { position: fixed; }

.col-menu {
  background-color: lightgreen;
}

.col-main {
    background-color: azure;
}

.col-footer {
    text-align: center;
    background-color: orange;
    padding: 10px;
    margin-bottom: 10px;
}

h1,h2,h3,h4,h5 { font-family: sans-serif; color: midnightblue; margin-top: 2%; } 
h1 {  font-size: 150%; font-variant: small-caps; }
h2 {  font-size: 115%; }
h3 {  text-align:left; font-size: 120%; }
h4 {  font-size: 105%; }
h5 {  font-size: 100%; }
h6 {  font-size: 100%; }
h7 {  text-align:center; font-family: sans-serif; font-size: 90%; }

center { text-align:center; }
thick { font-weight:bold; }

a:link { color:blue; text-decoration: none}
a:visited { color:midnightblue; text-decoration: none}*/
a:hover { text-decoration: underline }

ul { list-style-type: square; }
li { margin-top:1em; margin-bottom:1em; padding:0em }

.col-menu>ul {
  list-style-type: none;
  margin: 0;
  padding: 0;
}

.col-menu>ul>li {
    padding: 5px;
    margin-bottom: 1px;
}


.col-menu>ul>li>a:hover { background-color: green; }

.col-menu>ul>li>a {
    width: 100%;
}

a[target="_blank"]::before {
    content: "\2192  ";   
}

table, th, td {
    padding:15px;
    border: 1px solid black;
    border-collapse: collapse;
}

div.speakers>ol { width: 100%; }  /* float & allow room for the widest item */
div.speakers>ol>li { float: left; width: 40% ; }  /* stop the float */
div.speakers+* { clear: left; }  /* separate the list from subsequent markup */

@media not screen {
    background-color: white;
    .poster {display: none;}
}

[class*="logo"] {
    margin: 0 20px 0 0;
}