nav
{
    text-align: center;
    font-family: Arial, Helvetica, sans-serif;
}

body
{
  background-color:#f0f8ff;
  font-family: 'Times New Roman', Times, serif;
}

h1
{
    text-align: center;
    font-family: Arial, Helvetica, sans-serif;
}

h2
{
    font-family: Arial, Helvetica, sans-serif;
}


table {
  width: 100%;
  border-color:black;
  border-style: solid;
  margin-bottom: 1.5rem;
  background-color: white;
}

th, td {
  padding: 10px 10px;
  text-align: left;
  border-color:black;
  border-style: solid;
}

tr:first-child
{
  background-color: #7dffff;
}

nav
{
  font-size: large;
}

img
{
  height: 100px;
}

.screenshot
{
  text-align: center;
}

.popup {
  position: relative;
  display: inline-block;
  cursor: pointer;
}

/*The css code from the pop-up
comes from https://www.w3schools.com/howto/howto_js_popup.asp 
*/

.popup .popuptext {
  visibility: hidden;
  background-color: #555;
  border-radius: 6px;
  padding: 8px 0;
  position: absolute;
  z-index: 1;
  bottom: 125%;
  left: 50%;
  margin-left: -80px;
}

.popup .show {
  visibility: visible;
  -webkit-animation: fadeIn 1s;
  animation: fadeIn 1s
}