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

.stage {
  box-sizing: border-box;
  min-height: 100vh;
  display: grid;
  place-items: center;
  margin: 0;
  background: #17141a;
  font-family: -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
  padding: clamp(8px, 4vw, 24px);
}

.bt {
  display: grid;
  justify-items: center;
  gap: 12px;
  width: 100%;
}

.bt__art {
  display: block;
  width: clamp(176px, 60vw, 320px);
  height: auto;
}

.bt__seg {
  transform-box: view-box;
  transform-origin: var(--ox) var(--oy);
}

.bt__line {
  stroke-linecap: round;
}

.bt__line--a {
  stroke: #fff7e6;
}

.bt__line--b {
  stroke: #2f6df6;
}

.bt__bar {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: center;
  gap: 8px;
}

.bt__seed {
  margin: 0;
  display: inline-flex;
  align-items: center;
  gap: 4px;
  color: rgba(255, 247, 230, 0.8);
  font-weight: 700;
  font-size: clamp(9px, 2.4vw, 11px);
}

.bt__btn {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  border: 0;
  border-radius: 999px;
  padding: 4px 12px;
  background: #fff7e6;
  color: #17141a;
  font-family: inherit;
  font-weight: 700;
  font-size: clamp(9px, 2.4vw, 11px);
  cursor: pointer;
}

.bt__btn:focus-visible {
  outline: 3px solid #2f6df6;
  outline-offset: 2px;
}

.bt__ic {
  width: 12px;
  height: 12px;
  flex: none;
}

.bt.is-demo .bt__seg {
  animation-name: btGrow;
  animation-duration: 2s;
  animation-timing-function: cubic-bezier(0.7, 0, 0.85, 0.4);
  animation-iteration-count: infinite;
  animation-fill-mode: backwards;
  animation-delay: calc(var(--i) * 70ms);
}

.bt.is-draw .bt__seg {
  animation-name: btSprout;
  animation-duration: 600ms;
  animation-timing-function: ease-out;
  animation-iteration-count: 1;
  animation-fill-mode: backwards;
  animation-delay: calc(var(--i) * 60ms);
}

@keyframes btGrow {
  0% {
    transform: scale(0);
    animation-timing-function: cubic-bezier(0.7, 0, 0.85, 0.4);
  }
  40% {
    transform: scale(1);
    animation-timing-function: linear;
  }
  54% {
    transform: scale(1);
    animation-timing-function: ease-out;
  }
  86% {
    transform: scale(0);
  }
  100% {
    transform: scale(0);
  }
}
@keyframes btSprout {
  from {
    transform: scale(0);
  }
  to {
    transform: scale(1);
  }
}
@media (max-width: 340px) {
  .bt {
    gap: 8px;
  }
  .bt__ic {
    width: 10px;
    height: 10px;
  }
}
@media (prefers-reduced-motion: reduce) {
  .bt.is-demo .bt__seg,
  .bt.is-draw .bt__seg {
    animation: none !important;
    transform: scale(1) !important;
  }
}