.submenu
{
  width:430px;
}

.submenu ul {

  list-style-type: none;
  margin: 0;
  padding: 0;
  overflow: hidden;
  font-size: 16px;
  font-weight: bolder;
  width:410px;
}

.submenu li {
  float: left;
  border-right:1px solid #bbb;
  background-color: #333;
}

.submenu ul li:last-child {
  border-right: 1px solid #bbb;
  display: block;
}

.submenu ul li a {
  display: block;
  color: white;
  text-align: center;
  padding: 4px 6px;
  text-decoration: none;
}

.submenu li a:hover {
  background-color:#bbb;
}

.container {
  position: relative;
  /* overflow: hidden; */
  /* width: 100%;
  height:400px; */
  padding-top: 50%; 
  
}
/* Then style the iframe to fit in the container div with full height and width */
.responsive-iframe {
  border:0;
  position: absolute;
  top: 0;
  left: 0;
  bottom: 0;
  right: 0;
  width: 100%;
  height: 100%;
  line-height: 0;
}

pre
{
  font-size: 17px;
  font-family: 'Courier New', Courier, monospace;
  padding-left: 5px;
  font-weight:bold;
  white-space: pre-line;
  word-wrap: break-word;
  text-align: justify;
 /*  white-space: pre-wrap;
  word-wrap: break-word; */
  text-align: justify;
} 

.problem
{
  background-color:beige;
  font-weight: bold;
  border-top: 2px solid cadetblue;
  border-bottom:2px solid cadetblue;
}
h4
{
  padding-left:5px;
}
h5
{
  padding-left:5px;
}