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

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

.ck-list {
  list-style: none;
  margin: 0;
  padding: 0;
  width: min(240px, 78vw);
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.ck-item {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px;
  border-radius: 16px;
  background: #fff0f5;
}

.ck-item__box {
  position: relative;
  width: 24px;
  height: 24px;
  flex: 0 0 auto;
  border: 2px solid #ff9ebb;
  border-radius: 4px;
  background: #ffffff;
  cursor: pointer;
  display: grid;
  place-items: center;
  transition: background 300ms cubic-bezier(0.2, 1.4, 0.4, 1);
}

.ck-item__box:focus-visible {
  outline: 2px solid #2f6df6;
  outline-offset: 2px;
}

.ck-item__box svg {
  width: 14px;
  height: 14px;
  color: #ffffff;
  transform: scale(0.4);
  opacity: 0;
  transition: transform 300ms cubic-bezier(0.2, 1.4, 0.4, 1), opacity 300ms cubic-bezier(0.2, 1.4, 0.4, 1);
}

.ck-item.is-checked .ck-item__box {
  background: #ff9ebb;
}

.ck-item.is-checked .ck-item__box svg {
  transform: scale(1);
  opacity: 1;
}

.ck-item__text {
  position: relative;
  font-size: 13px;
  color: #17141a;
  transition: opacity 300ms cubic-bezier(0.2, 1.4, 0.4, 1);
}

.ck-item__text::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: 50%;
  height: 2px;
  background: #ff9ebb;
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 300ms cubic-bezier(0.2, 1.4, 0.4, 1);
}

.ck-item.is-checked .ck-item__text {
  opacity: 0.5;
}

.ck-item.is-checked .ck-item__text::after {
  transform: scaleX(1);
}

.ck-item.is-demo .ck-item__box {
  animation: ck-box-loop 2s cubic-bezier(0.2, 1.4, 0.4, 1) infinite;
}

.ck-item.is-demo .ck-item__box svg {
  animation: ck-check-loop 2s cubic-bezier(0.2, 1.4, 0.4, 1) infinite;
}

.ck-item.is-demo .ck-item__text {
  animation: ck-text-loop 2s cubic-bezier(0.2, 1.4, 0.4, 1) infinite;
}

.ck-item.is-demo .ck-item__text::after {
  animation: ck-line-loop 2s cubic-bezier(0.2, 1.4, 0.4, 1) infinite;
}

@keyframes ck-box-loop {
  0%, 10% {
    background: #ffffff;
  }
  35%, 80% {
    background: #ff9ebb;
  }
  95%, 100% {
    background: #ffffff;
  }
}
@keyframes ck-check-loop {
  0%, 10% {
    transform: scale(0.4);
    opacity: 0;
  }
  40% {
    transform: scale(1.15);
    opacity: 1;
  }
  50%, 80% {
    transform: scale(1);
    opacity: 1;
  }
  95%, 100% {
    transform: scale(0.4);
    opacity: 0;
  }
}
@keyframes ck-text-loop {
  0%, 10% {
    opacity: 1;
  }
  35%, 80% {
    opacity: 0.5;
  }
  95%, 100% {
    opacity: 1;
  }
}
@keyframes ck-line-loop {
  0%, 10% {
    transform: scaleX(0);
  }
  40%, 80% {
    transform: scaleX(1);
  }
  95%, 100% {
    transform: scaleX(0);
  }
}
@media (prefers-reduced-motion: reduce) {
  .ck-item__box, .ck-item__box svg, .ck-item__text, .ck-item__text::after {
    transition: none;
  }
}