.vibration {
  display: flex;
  justify-content: center;

  margin-top: 220px;
}

.vibration__button {
  /* Margin, paddings */
  padding: 9px 15px;

  font-size: 20px;
  background-color: #f1f1f1;
  cursor: pointer;
  border: none;
  border-radius: 5px;
}

.vibration__button:hover {
  background-color: #cccccc;
}

.vibration__button:not(:last-child) {
  margin-right: 20px;
}

@media only screen and (max-width: 320px) {
  .vibration {
    display: block;
    margin-top: 10px;
  }

  .vibration__button {
    width: 100%;
    max-width: 300px;

    margin-bottom: 10px;
  }

  .vibration__button:not(:last-child) {
    margin-right: 0px;
  }
}