.cards {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  padding: 0 20px;
}
div {
  padding: 70px 50px;
  margin: 20px;
  border-radius: 5%;
  color: white;
  font-weight: bold;
}
.green {
  background: green;
}
.blue {
  background: blue;
}
.red {
  background: red;
}
.yellow {
  background: yellow;
}
button {
  background: white;
  border: solid 1px black;
  padding: 10px;
  border-radius: 10px;
}