body {
  margin: 0;
}

header {
  color: silver;
  background-color: black;
  height: 60px;
  border-bottom: green 2px dotted;
  padding: 30px;
  text-align: center;
  font-size: 60px;
}
.container {
  background-image: url(http://cdn.playbuzz.com/cdn/4f027569-d451-43f0-b51b-db41e63a64af/9d180e8d-786e-4a91-ad0a-5074a68e358f_560_420.jpg);
  background-size: cover;
  min-height: 85vh;
  background-color: rgba(255, 255, 255, 0.85);
  display: flex;
  flex-direction: column;
  align-items: center;
}
section {
  width: 100%;
  text-align: center;
}
.addBtn {
  width: 200px;
  margin: 20px;
  line-height: 2em;
  font-size: 2em;
  text-transform: uppercase;
  background-color: #000;
  color: #fff;
  border: 1px solid rgba(0, 0, 0, 0.2);
  border-bottom-width: 2px;
  border-radius: 5px; font-size: inherit;
  padding: .5em 1em;
  cursor: pointer;
}
main {
  width: 100%;
  background-color: rgba(255, 255, 255, 0.9);
  padding: 5em;
  flex-grow: 1;
  text-align: center;
}
section,
.planetContainer {
  padding-top: 30px;
  background-color: rgba(255, 255, 255, 0.85);
}
.planetContainer {
  display: flex;
  flex-wrap: wrap;
  flex-basis: 400px;
  overflow-y: scroll;
}
.planet {
  cursor: pointer;
  padding: 2em;
  height: 40px;
  min-width: 40px;
  border: 2px solid black;
  margin: 5px;
  background-color: rgba(0, 0, 0, 0.5);
  color: #fff;
  border-radius: 5%;
  position: relative;
}
.removeBtn {
  cursor: inherit;
  color: inherit;
  position: absolute;
  top: 0;
  right: 0;
  background-color: #000;
}