html,
body {
  height: 100%;
}

*,
*::before,
*::after {
  box-sizing: border-box;
  touch-action: manipulation;
}

body {
  display: flex;
  margin: 0;
  font: 14px -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background: #079992;
  perspective: 3000px;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  color: #fff;
  gap: 3rem;
}

.calendar {
  width: 360px;
  height: 430px;
  color: gray;
  background: #fff;
  border-radius: 1rem;
  padding: 1rem;
  transform-origin: 50% 100%;
  transition: 0.5s transform ease-in;
}

.calendar.fallen {
  transform: rotateX(92deg);
}

.controls {
  display: flex;
  flex-flow: column;
  align-items: center;
}

.controls > * {
  width: 100%;
}

.select {
  width: 100%;
  text-align: center;
  display: grid;
}

.select::before {
  content: attr(data-value);
  grid-area: 1/1;
}

.select select {
  grid-area: 1/1;
  opacity: 0;
  cursor: pointer;
}

.slider {
  width: 100%;
  text-align: center;
  display: grid;
}

.slider::before {
  content: attr(data-value);
  grid-area: 1/1;
  display: flex;
  align-items: center;
  justify-content: center;
}

.slider input:active,
.slider input:active + div {
  opacity: 1;
}

.slider input,
.slider div {
  grid-area: 1/1;
  opacity: 0;
  transition: 0.3s opacity;
}

.slider input {
  z-index: 1;
  cursor: pointer;
  width: 100%;
}

.slider div {
  background: #fff;
}

.buttons {
  display: flex;
  gap: 0.5rem;
}

.buttons > * {
  flex: 1;
}

.buttons button {
  flex: 0;
  background: transparent;
  transition: 0.3s background;
  border: 0;
  border-radius: 0.25rem;
  padding: 0.5rem 1rem;
  cursor: pointer;
  color: inherit;
  font: inherit;
}

.buttons button:hover {
  background: #eee;
}

.buttons button svg {
  width: 16px;
  height: 16px;
  stroke: currentColor;
  stroke-width: 2;
  fill: none;
  stroke-linecap: round;
  stroke-linejoin: round;
  vertical-align: middle;
}

.month {
  display: grid;
  margin-top: 2rem;
  gap: 0.125rem;
  grid-template-columns: repeat(7, 1fr);
}

.month span {
  text-align: center;
  padding: 0.25rem;
  font-size: 0.8rem;
  font-weight: bold;
}

.month button {
  position: relative;
  border: 0;
  background: transparent;
  font: inherit;
  color: inherit;
  cursor: pointer;
  padding: 0;
  border-radius: 50%;
  transition: 0.3s background;
}

.month button:hover {
  background: #eee;
}

.month button::after {
  content: attr(data-day);
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
}

.month button::before {
  margin-top: 100%;
  content: "";
  display: block;
}

cite {
  font-size: 0.8rem;
}

a {
  color: inherit;
}