body, html {
  height: 100%;
  margin: 0;
}
.example_d {
  color: #20bf6b !important;
  text-transform: uppercase;
  background: #ffffff;
  padding: 20px;
  border: 4px solid #20bf6b !important;
  border-radius: 6px;
  display: inline-block;
  transition: all 0.3s ease 0s;
}

.example_d:hover {
  color: #494949 !important;
  border-radius: 50px;
  border-color: #494949 !important;
  transition: all 0.3s ease 0s;
}

.container{
  width:100%;
  height:2000px;
  overflow:hidden;
}
.img {
  width:100%;
}