#table-wrapper {
  position:relative;
}
#table-scroll {
  height: 750px;
  overflow:auto;  
  margin-top:20px;
}

#table-wrapper table {
  width:75%;
  position:center;
}

table {
  border-collapse: collapse;
  width: 50%;
}

tr:hover {background-color: #D6EEEE;}

th {
  position: sticky;
  top: 0;
  background: white;
  padding: 8px;
  text-align: left;
  border-bottom: 1px solid #DDD;
}

td {
  padding: 8px;
  text-align: left;
  border-bottom: 1px solid #DDD;
}