.fa:hover {
    opacity: 0.7;
}
.body
{
  background-color: green;
}
.b1
{
  background-color:black;
  border-radius: 10px;
  padding-left: 15px;
  padding-right: 15px;
  padding-top: 10px;
  padding-bottom: 10px;
  color:white;
}
.b1:hover
{
  color:grey;
}

.dropbtn {
  background-color: black;
  color: white;
  padding: 16px;
  font-size: 16px;
  border: none;
}

.dropdown {
  position: relative;
  display: inline-block;
}

.dropdown-content {
  display: none;
  position: absolute;
  background-color: blue;
  min-width: 160px;
  box-shadow: 0px 8px 16px 0px rgba(0,0,0,0.2);
  z-index: 1;
}

.dropdown-content a {
  color: black;
  padding: 12px 16px;
  text-decoration: none;
  display: block;
}

.dropdown-content a:hover {background-color: #ddd;}

.dropdown:hover .dropdown-content {display: block;}

.dropdown:hover .dropbtn {background-color: #3e8e41;}