html, body {
  margin: 0;
  overflow: hidden;
}

.stage {
  box-sizing: border-box;
  min-height: 100vh;
  display: grid;
  place-items: center;
  margin: 0;
  background: #ffd23f;
  font-family: -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
  padding: clamp(8px, 4vw, 24px);
}

.qs {
  --cell: 56px;
  box-sizing: border-box;
  display: grid;
  grid-template-rows: 1fr auto;
  align-items: center;
  gap: 16px;
  width: clamp(288px, 92vw, 392px);
}

.qs__body {
  display: grid;
  grid-template-rows: auto auto;
}

.qs__quote {
  grid-area: 1/1;
  margin: 0;
  color: #1c1b22;
  font-weight: 700;
  font-size: clamp(17px, 4.4vw, 22px);
  line-height: 1.4;
  opacity: 0;
  visibility: hidden;
}

.qs__quote.is-on {
  opacity: 1;
  visibility: visible;
}

.qs__by {
  grid-area: 2/1;
  align-self: start;
  margin: 0;
  padding-top: 12px;
  color: #1c1b22;
  font-weight: 500;
  font-size: 12.5px;
  line-height: 1.3;
  opacity: 0;
  visibility: hidden;
}

.qs__by.is-on {
  opacity: 1;
  visibility: visible;
}

.qs__rail {
  --i: 0;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  width: calc(4 * var(--cell));
}

.qs__ring {
  grid-row: 1;
  grid-column: 1;
  border: 3px solid #1c1b22;
  border-radius: 50%;
  pointer-events: none;
  transform: translateX(calc(var(--i) * 100%));
  transition: transform 300ms cubic-bezier(0.2, 0.8, 0.2, 1);
}

.qs__cell {
  grid-row: 1;
  display: grid;
  place-items: center;
  width: var(--cell);
  height: var(--cell);
}

.qs__cell:nth-child(2) {
  grid-column: 1;
}

.qs__cell:nth-child(3) {
  grid-column: 2;
}

.qs__cell:nth-child(4) {
  grid-column: 3;
}

.qs__cell:nth-child(5) {
  grid-column: 4;
}

.qs__face {
  display: grid;
  place-items: center;
  width: 48px;
  height: 48px;
  padding: 0;
  border: 0;
  border-radius: 50%;
  background: rgba(28, 27, 34, 0.14);
  color: #1c1b22;
  cursor: pointer;
  transform: translateY(0);
  transition: transform 220ms cubic-bezier(0.2, 1.4, 0.4, 1), background-color 220ms ease-out;
}

.qs__initial {
  font-weight: 700;
  font-size: 15px;
  line-height: 1;
}

.qs__face.is-on {
  background: #fbf7ef;
  transform: translateY(-4px);
}

.qs__face:focus-visible {
  outline: 2px solid #1c1b22;
  outline-offset: 3px;
}

.qs.is-demo .qs__quote,
.qs.is-demo .qs__by {
  animation-name: qsCut;
  animation-duration: 2s;
  animation-timing-function: steps(1, end);
  animation-iteration-count: infinite;
  animation-fill-mode: backwards;
  visibility: visible;
}

.qs.is-demo .qs__quote--1 {
  animation-delay: -2s;
}

.qs.is-demo .qs__quote--2 {
  animation-delay: -1.5s;
}

.qs.is-demo .qs__quote--3 {
  animation-delay: -1s;
}

.qs.is-demo .qs__quote--4 {
  animation-delay: -0.5s;
}

.qs.is-demo .qs__by--1 {
  animation-delay: -2s;
}

.qs.is-demo .qs__by--2 {
  animation-delay: -1.5s;
}

.qs.is-demo .qs__by--3 {
  animation-delay: -1s;
}

.qs.is-demo .qs__by--4 {
  animation-delay: -0.5s;
}

.qs.is-demo .qs__ring {
  animation-name: qsRing;
  animation-duration: 2s;
  animation-timing-function: cubic-bezier(0.2, 0.8, 0.2, 1);
  animation-iteration-count: infinite;
  animation-fill-mode: backwards;
}

.qs.is-demo .qs__face {
  animation-name: qsFacePop, qsFaceTone;
  animation-duration: 2s, 2s;
  animation-timing-function: cubic-bezier(0.2, 1.4, 0.4, 1), steps(1, end);
  animation-iteration-count: infinite, infinite;
  animation-fill-mode: backwards, backwards;
  transition: none;
}

.qs.is-demo .qs__face--1 {
  animation-delay: -2s, -2s;
}

.qs.is-demo .qs__face--2 {
  animation-delay: -1.5s, -1.5s;
}

.qs.is-demo .qs__face--3 {
  animation-delay: -1s, -1s;
}

.qs.is-demo .qs__face--4 {
  animation-delay: -0.5s, -0.5s;
}

@keyframes qsCut {
  0% {
    opacity: 1;
  }
  25% {
    opacity: 0;
  }
  100% {
    opacity: 0;
  }
}
@keyframes qsRing {
  0%, 16% {
    transform: translateX(0);
  }
  24.5%, 41% {
    transform: translateX(100%);
  }
  49.5%, 66% {
    transform: translateX(200%);
  }
  74.5%, 79% {
    transform: translateX(300%);
  }
  88%, 100% {
    transform: translateX(0);
  }
}
@keyframes qsFacePop {
  0% {
    transform: translateY(0);
  }
  6% {
    transform: translateY(-4px);
  }
  19% {
    transform: translateY(-4px);
  }
  25%, 100% {
    transform: translateY(0);
  }
}
@keyframes qsFaceTone {
  0% {
    background-color: #fbf7ef;
  }
  25%, 100% {
    background-color: rgba(28, 27, 34, 0.14);
  }
}
@media (max-width: 340px), (max-height: 220px) {
  .qs {
    gap: 8px;
    width: 100%;
  }
  .qs__quote {
    font-size: 13.5px;
    line-height: 1.45;
  }
  .qs__by {
    font-size: 10.5px;
    padding-top: 8px;
  }
  .qs {
    --cell: 40px;
  }
  .qs__face {
    width: 32px;
    height: 32px;
  }
  .qs__initial {
    font-size: 12px;
  }
  .qs__ring {
    border-width: 2px;
  }
}
@media (prefers-reduced-motion: reduce) {
  .qs__quote, .qs__by, .qs__ring, .qs__face {
    animation: none !important;
    transition: none !important;
  }
  .qs__quote, .qs__by {
    opacity: 0 !important;
    visibility: hidden !important;
  }
  .qs__quote.is-on, .qs__by.is-on {
    opacity: 1 !important;
    visibility: visible !important;
  }
}