.header {
  background-image: url("https://singularityhub.com/wp-content/uploads/2018/08/circuit-board-electronic-computer-hardware-technology_shutterstock_515152267.jpg"); 
  padding: 20px;
  color:white; 
  text-align:center;
}

.column {float: left;
  width: 30%;
  padding: 15px;
}

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

/* Dropdown Button */
.dropbtn {
  background-color: #3498DB;
  color: white;
  padding: 16px;
  font-size: 16px;
  border: none;
  cursor: pointer;
  width: 24%;
  border-radius: 10px;
  position: sticky;
}

/* Dropdown button on hover & focus */
.dropbtn:hover, .dropbtn:focus {
  background-color: #ddd;
  color: black;
}

/* The container <div> - needed to position the dropdown content */
.dropdown {
  position: relative;
  display: inline-block;
}

/* Dropdown Content (Hidden by Default) */
.dropdown-content {
  display: none;
  position: sticky;
  top: 70px;
  background-color: #3f98d4;
  min-width: 160px;
  box-shadow: 0px 8px 16px 0px rgba(0,0,0,0.2);
  z-index: 1;
  width: 24%;
  border-radius: 10px;
  Opacity:90%;
}

.dropdown-content h1 {
  font-size: 20px;
  padding: 0px 20px;
  
}

#myDropdown1{
  position: sticky;
  top: 70px;
  left: 24%;
}

#myDropdown2{
  position: sticky;
  top: 70px;
  left: 48%;
}

#myDropdown3{
  position: sticky;
  top: 70px;
  left: 73%;
}
/* Links inside the dropdown */
.dropdown-content a {
  color: black;
  padding: 12px 16px;
  text-decoration: none;
  display: block;
}

#myDropdown2 a {
  display: inline-block;  
}

#myDropdown3 button {display: inline-block;
  width: 35%; 
  background-color: #3498DB;
  color: black;
  padding: 16px;
  font-size: 16px;
  border: none;
  cursor: pointer;
  border-radius: 10px;
  position: sticky;
}

#myDropdown3 button:hover, #myDropdown3 button:focus {
  background-color: #ddd;
  color: black;
}
.line a {
  display: inline-block;  
}

.topnav {position:sticky; top:10px;background-color:#3f98d4; overflow: hidden; justify-content:space-between;border-radius: 10px; opacity:90%}


/* Change color of dropdown links on hover */
.dropdown-content a:hover {background-color: #ddd;
border-radius: 10px;
}
/* Show the dropdown menu (use JS to add this class to the .dropdown-content container when the user clicks on the dropdown button) */
.show {display:block;}

body {background-color:lightblue;}

h2 {color:red;}

.footer {
  position: fixed; 
  left: 0px; 
  bottom: 10px; 
  width: 100%; 
  background-color: #3f98d4; 
  color: white; 
  text-align: center; 
  border-radius: 10px; 
  Opacity:90%;
}

#footer{
  font-size:25;
  line-height:50%
}

.br {height: 10px;}

.show {display:block;}