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);
}

.sac {
  display: grid;
  justify-items: center;
  gap: 16px;
}

.sac__ringwrap {
  position: relative;
  display: grid;
  place-items: center;
}

.sac__ring {
  transform: rotate(-90deg);
}

.sac__track {
  fill: none;
  stroke: rgba(23, 20, 26, 0.12);
  stroke-width: 8;
}

.sac__prog {
  fill: none;
  stroke: #0a4fe8;
  stroke-width: 8;
  stroke-linecap: round;
  transition: stroke 300ms ease-out;
}

.sac--saving .sac__prog {
  stroke: #4cd4a6;
}

.sac__mid {
  position: absolute;
  display: grid;
  justify-items: center;
}

.sac__num {
  font: 800 30px/1 -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
  color: #17141a;
  font-variant-numeric: tabular-nums;
}

.sac__unit {
  font: 500 10px/1 -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
  color: rgba(23, 20, 26, 0.6);
}

.sac__btn {
  border: 0;
  border-radius: 12px;
  padding: 8px 16px;
  background: #17141a;
  color: #fff7e6;
  font: 700 13px/1 -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
  cursor: pointer;
  transition: transform 140ms ease-out;
}
.sac__btn:active {
  transform: scale(0.96);
}

@media (max-width: 340px) {
  .sac__ring {
    width: 92px;
    height: 92px;
  }
  .sac__num {
    font-size: 24px;
  }
}
@media (prefers-reduced-motion: reduce) {
  .sac__prog {
    transition: none;
  }
  .sac__btn {
    transition: none;
  }
}