header {
  display: flex;
  justify-content: space-between;
  padding: 30px calc(max(30px, (100vw - 900px) / 2));
  align-items: center;
}

#countOut {
  font-size: 30px;
  font-weight: bold;
}

#cards {
  padding: 30px calc((100vw - 900px) / 2);
  display: flex;
  flex-direction: column;
  gap: 40px;
  background-color: #bbb;
  min-height: calc(100vh - 200px);
}

.card {
  width: 400px;
  font-size: 30px;
  background-color: #eee;
  padding: 40px;
  border-radius: 30px;
  display: flex;
  flex-direction: column;
  gap: 30px;
}

.selected {
  background-color: #ccc;
}

:not(.selected)>.del-btn {
  display: none;
}