@charset "UTF-8";
html, body {
  margin: 0;
  overflow: hidden;
}

.stage {
  box-sizing: border-box;
  min-height: 100vh;
  display: grid;
  place-items: center;
  margin: 0;
  background: #e8e6f0;
  font-family: -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
  padding: clamp(8px, 4vw, 24px);
}

.nu {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 20px;
}

.nu__dock {
  display: flex;
  gap: 12px;
  padding: 12px 16px;
  border-radius: 999px;
  background: #e8e6f0;
  box-shadow: 8px 8px 16px #a9a3c0, -8px -8px 16px #ffffff;
}

.nu__btn {
  flex: 0 0 auto;
  width: 48px;
  height: 48px;
  display: grid;
  place-items: center;
  padding: 0;
  border: 0;
  border-radius: 50%;
  background: #e8e6f0;
  color: rgba(60, 54, 84, 0.6);
  cursor: pointer;
  /* 떠오른 상태 — 바깥 그림자 두 개 */
  box-shadow: 5px 5px 10px #a9a3c0, -5px -5px 10px #ffffff;
  transition: box-shadow 220ms ease-out, color 220ms ease-out;
}

.nu__btn svg {
  width: 22px;
  height: 22px;
  display: block;
}

.nu__btn:focus-visible {
  outline: 2px solid #6d5fae;
  outline-offset: 4px;
}

.nu__btn[aria-pressed=true] {
  color: #6d5fae;
  /* 눌린 상태 — 같은 그림자를 inset 으로 뒤집는다 */
  box-shadow: inset 5px 5px 10px #a9a3c0, inset -5px -5px 10px #ffffff;
}

.nu__cap {
  margin: 0;
  font-size: 13px;
  line-height: 1.5;
  color: rgba(60, 54, 84, 0.82);
}

/* 자동 재생 — 왼쪽부터 하나씩 눌렸다 떠오른다. 마지막은 84% 에 풀린다 */
.is-demo .nu__btn {
  animation-name: nu-press;
  animation-duration: 2s;
  animation-timing-function: ease-out;
  animation-iteration-count: infinite;
}

.is-demo .nu__btn:nth-child(2) {
  animation-delay: 0.34s;
}

.is-demo .nu__btn:nth-child(3) {
  animation-delay: 0.68s;
}

.is-demo .nu__btn:nth-child(4) {
  animation-delay: 1.02s;
}

.is-demo .nu__btn:nth-child(5) {
  animation-delay: 1.36s;
}

@keyframes nu-press {
  0% {
    box-shadow: 5px 5px 10px #a9a3c0, -5px -5px 10px #ffffff;
    color: rgba(60, 54, 84, 0.6);
  }
  8% {
    box-shadow: inset 5px 5px 10px #a9a3c0, inset -5px -5px 10px #ffffff;
    color: #6d5fae;
  }
  17% {
    box-shadow: inset 5px 5px 10px #a9a3c0, inset -5px -5px 10px #ffffff;
    color: #6d5fae;
  }
  24% {
    box-shadow: 5px 5px 10px #a9a3c0, -5px -5px 10px #ffffff;
    color: rgba(60, 54, 84, 0.6);
  }
  100% {
    box-shadow: 5px 5px 10px #a9a3c0, -5px -5px 10px #ffffff;
    color: rgba(60, 54, 84, 0.6);
  }
}
@media (max-width: 340px) {
  .nu__dock {
    gap: 8px;
    padding: 8px 12px;
  }
  .nu__btn {
    width: 44px;
    height: 44px;
  }
}
@media (prefers-reduced-motion: reduce) {
  .is-demo .nu__btn {
    animation-name: none;
  }
  .nu__btn {
    transition: none;
  }
}