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);
}

.eq {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
}

.eq__key {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 62px;
  height: 62px;
  margin: 0;
  padding: 0;
  border: 0;
  border-radius: 12px;
  cursor: pointer;
  color: #17141a;
  background-color: rgba(23, 20, 26, 0.09);
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.65), inset 0 -2px 0 rgba(23, 20, 26, 0.18), 0 3px 0 rgba(23, 20, 26, 0.16), 0 6px 5px rgba(23, 20, 26, 0.15);
  transform: translateY(0);
  transition: transform 140ms cubic-bezier(0.2, 0.8, 0.2, 1), box-shadow 140ms cubic-bezier(0.2, 0.8, 0.2, 1), background-color 220ms ease-out, color 220ms ease-out;
}

.eq__key:active {
  transform: translateY(2px);
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.65), inset 0 -2px 0 rgba(23, 20, 26, 0.18), 0 1px 0 rgba(23, 20, 26, 0.16), 0 2px 2px rgba(23, 20, 26, 0.12);
}

.eq__key:focus-visible {
  outline: 2px solid #0a4fe8;
  outline-offset: 3px;
}

.eq__key.is-on {
  background-color: #0a4fe8;
  color: #fff7e6;
}

.eq__icon {
  width: 30px;
  height: 30px;
}

.eq__key.is-on .eq__icon path[opacity=".2"] {
  opacity: 0.7;
}

.eq.is-demo .eq__key {
  animation-name: eqPress, eqFill, eqIcon;
  animation-duration: 2s;
  animation-timing-function: cubic-bezier(0.2, 0.8, 0.2, 1), steps(1, end), steps(1, end);
  animation-iteration-count: infinite;
}

.eq.is-demo .eq__key:nth-child(2) {
  animation-delay: calc(2s / -3 * 2);
}

.eq.is-demo .eq__key:nth-child(3) {
  animation-delay: calc(2s / -3);
}

@keyframes eqPress {
  0% {
    transform: translateY(0);
    box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.65), inset 0 -2px 0 rgba(23, 20, 26, 0.18), 0 3px 0 rgba(23, 20, 26, 0.16), 0 6px 5px rgba(23, 20, 26, 0.15);
  }
  3% {
    transform: translateY(2px);
    box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.65), inset 0 -2px 0 rgba(23, 20, 26, 0.18), 0 1px 0 rgba(23, 20, 26, 0.16), 0 2px 2px rgba(23, 20, 26, 0.12);
  }
  8%, 100% {
    transform: translateY(0);
    box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.65), inset 0 -2px 0 rgba(23, 20, 26, 0.18), 0 3px 0 rgba(23, 20, 26, 0.16), 0 6px 5px rgba(23, 20, 26, 0.15);
  }
}
@keyframes eqFill {
  0%, 4% {
    background-color: rgba(23, 20, 26, 0.09);
  }
  10%, 40% {
    background-color: #0a4fe8;
  }
  46%, 100% {
    background-color: rgba(23, 20, 26, 0.09);
  }
}
@keyframes eqIcon {
  0%, 4% {
    color: #17141a;
  }
  10% {
    color: #fff7e6;
  }
  46%, 100% {
    color: #17141a;
  }
}
@media (max-width: 340px) {
  .eq__key {
    width: 48px;
    height: 48px;
  }
  .eq__icon {
    width: 20px;
    height: 20px;
  }
}
@media (prefers-reduced-motion: reduce) {
  .eq .eq__key {
    transition: none !important;
  }
  .eq.is-demo .eq__key {
    animation: none !important;
  }
}