.instrument-main {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 0 16px 60px;
}

.piano-explainer {
  width: min(96vw, 680px);
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.section-title {
  margin: 0;
  font-size: 1.4rem;
  text-align: center;
}

.intro-text,
.summary-text {
  margin: 0;
  color: #cfd8ff;
  font-size: 1rem;
  line-height: 1.5;
  text-align: center;
}

.summary-text {
  color: #ffd166;
  font-weight: bold;
  margin-top: 8px;
}

.step-list {
  list-style: none;
  margin: 8px 0 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.step-card {
  position: relative;
  padding: 16px 52px 16px 16px;
  border-radius: 16px;
  border: 1px solid rgba(255, 255, 255, 0.15);
  background: rgba(255, 255, 255, 0.06);
}

.step-card h3 {
  margin: 0 0 8px;
  font-size: 1.05rem;
  color: #ffd166;
}

.step-card p {
  margin: 0;
  color: #e8ecff;
  font-size: 0.95rem;
  line-height: 1.45;
}

.step-icon {
  position: absolute;
  top: 16px;
  right: 16px;
  font-size: 1.6rem;
}

.coming-soon {
  margin: 8px 0 0;
  color: #94a3b8;
  font-size: 0.95rem;
  text-align: center;
}

.piano-play {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 14px;
  margin-top: 12px;
  padding-top: 20px;
  border-top: 1px solid rgba(255, 255, 255, 0.12);
  width: 100%;
}

.piano-canvas {
  width: 100%;
  max-width: 640px;
  border-radius: 16px;
  border: 1px solid rgba(255, 255, 255, 0.15);
  background: #2a2040;
  touch-action: none;
}

.piano-keyboard {
  display: flex;
  justify-content: center;
  gap: 6px;
  width: 100%;
  max-width: 640px;
  padding: 4px 0;
}

.piano-key {
  flex: 1 1 0;
  min-width: 0;
  min-height: 88px;
  padding: 8px 4px;
  border-radius: 0 0 10px 10px;
  border: 2px solid rgba(0, 0, 0, 0.15);
  border-top: none;
  background: linear-gradient(180deg, #fff 0%, #e8ecf4 100%);
  color: #334155;
  cursor: pointer;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: flex-end;
  gap: 2px;
  transition: transform 0.06s ease, background 0.06s ease;
  touch-action: manipulation;
  user-select: none;
}

.piano-key:hover {
  background: linear-gradient(180deg, #fff 0%, #dce3ef 100%);
}

.piano-key.pressed,
.piano-key:active {
  transform: translateY(3px);
  background: linear-gradient(180deg, #dce3ef 0%, #cbd5e1 100%);
}

.piano-key-label {
  font-size: 0.95rem;
  font-weight: bold;
  color: #1e293b;
}

.piano-key-note {
  font-size: 0.65rem;
  color: #64748b;
}

.why-box {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  min-height: 2.5rem;
}

.why-btn {
  padding: 8px 18px;
  border-radius: 999px;
  border: 1px solid rgba(255, 255, 255, 0.25);
  background: rgba(255, 255, 255, 0.05);
  color: #cfd8ff;
  cursor: pointer;
}

.why-text {
  margin: 0;
  max-width: 28rem;
  text-align: center;
  color: #7dffb3;
  font-size: 0.95rem;
  line-height: 1.4;
}

.why-text[hidden] {
  display: none !important;
}

.song-play {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 10px;
  width: 100%;
  max-width: 640px;
  padding: 14px;
  border-radius: 16px;
  border: 1px solid rgba(255, 255, 255, 0.12);
  background: rgba(255, 255, 255, 0.04);
}

.song-title {
  margin: 0;
  font-size: 1.05rem;
  color: #ffd166;
}

.song-hint {
  margin: 0;
  color: #cfd8ff;
  font-size: 0.9rem;
  text-align: center;
}

.song-chips {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 6px;
}

.song-chip {
  width: 30px;
  height: 30px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 8px;
  font-size: 0.8rem;
  font-weight: bold;
  color: #cfd8ff;
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.16);
}

.song-chip.done {
  color: #1b1035;
  background: #06d6a0;
  border-color: transparent;
}

.song-chip.current {
  color: #1b1035;
  background: #ffd166;
  border-color: transparent;
  animation: song-chip-pulse 0.9s ease-in-out infinite;
}

@keyframes song-chip-pulse {
  0%, 100% { transform: scale(1); }
  50% { transform: scale(1.14); }
}

.piano-key.song-next {
  box-shadow: 0 0 0 3px #ffd166, 0 0 14px 2px rgba(255, 209, 102, 0.7);
}

.song-done {
  margin: 0;
  color: #7dffb3;
  font-weight: bold;
  font-size: 0.95rem;
}

.song-done[hidden] {
  display: none;
}

@media (prefers-reduced-motion: reduce) {
  .song-chip.current {
    animation: none;
  }
}

.play-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  justify-content: center;
}

.secondary-btn {
  padding: 10px 20px;
  border-radius: 999px;
  border: 1px solid rgba(255, 255, 255, 0.25);
  background: rgba(255, 255, 255, 0.06);
  color: #cfd8ff;
  font-size: 0.9rem;
  cursor: pointer;
}

.secondary-btn:hover {
  background: rgba(255, 255, 255, 0.14);
}

@media (max-width: 480px) {
  .piano-key {
    min-height: 72px;
  }

  .piano-key-label {
    font-size: 0.8rem;
  }

  .piano-key-note {
    display: none;
  }
}

/* ================= 악기나라 로비 + 화면 전환 ================= */
.inst-soundbar {
  width: min(96vw, 680px);
  margin: 0 auto 6px;
  display: flex;
  justify-content: flex-end;
}

.inst-lobby {
  width: min(96vw, 680px);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
  text-align: center;
}

.inst-lobby[hidden] {
  display: none;
}

.inst-card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  gap: 14px;
  width: 100%;
  margin-top: 6px;
}

.inst-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
  padding: 18px 12px;
  border-radius: 16px;
  border: 1px solid rgba(255, 255, 255, 0.15);
  border-top: 3px solid #ff85a1;
  background: rgba(255, 255, 255, 0.06);
  color: inherit;
  cursor: pointer;
  transition: transform 0.15s ease, background 0.15s ease, border-color 0.15s ease;
}

.inst-card:hover,
.inst-card:focus-visible {
  transform: translateY(-3px);
  background: rgba(255, 255, 255, 0.1);
  border-color: #ff85a1;
}

.inst-card-icon {
  font-size: 2rem;
  line-height: 1;
}

.inst-card-name {
  font-size: 1.05rem;
  font-weight: bold;
}

.inst-card-desc {
  font-size: 0.82rem;
  color: #b9c2e6;
  line-height: 1.35;
}

.inst-screen {
  width: min(96vw, 680px);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 14px;
}

.inst-screen[hidden] {
  display: none;
}

.inst-back-btn {
  align-self: flex-start;
  padding: 8px 18px;
  border-radius: 999px;
  border: 1px solid rgba(255, 255, 255, 0.25);
  background: rgba(255, 255, 255, 0.05);
  color: #cfd8ff;
  font-size: 0.85rem;
  cursor: pointer;
}

.inst-back-btn:hover {
  background: rgba(255, 255, 255, 0.15);
}

.chip-btn {
  padding: 8px 18px;
  border-radius: 999px;
  border: 1px solid rgba(255, 255, 255, 0.25);
  background: rgba(255, 255, 255, 0.05);
  color: #cfd8ff;
  font-size: 0.85rem;
  cursor: pointer;
  transition: background 0.15s ease, color 0.15s ease;
}

.chip-btn.active {
  background: linear-gradient(90deg, #ffd166, #ff85a1);
  color: #1b1035;
  border-color: transparent;
  font-weight: bold;
}

/* ================= 기타 ================= */
.guitar-board {
  width: 100%;
  max-width: 460px;
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: 18px 16px;
  border-radius: 16px;
  background: linear-gradient(180deg, #4a2f1e, #35211405);
  background-color: #3a2517;
  border: 1px solid rgba(255, 255, 255, 0.12);
}

.guitar-string {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 10px 6px;
  background: none;
  border: none;
  cursor: pointer;
}

.guitar-string-label {
  flex: 0 0 3.4rem;
  text-align: right;
  font-size: 0.8rem;
  color: #e8d3b0;
}

.guitar-wire {
  flex: 1;
  display: block;
  min-height: 2px;
  border-radius: 999px;
  background: linear-gradient(180deg, #f8fafc, #94a3b8);
  box-shadow: 0 0 6px rgba(255, 255, 255, 0.25);
}

.guitar-wire.plucking {
  animation: guitar-wobble var(--wob, 0.6s) ease-out 1;
}

@keyframes guitar-wobble {
  0%,
  100% {
    transform: translateY(0);
  }
  12% {
    transform: translateY(calc(-1 * var(--amp, 6px)));
  }
  28% {
    transform: translateY(calc(0.62 * var(--amp, 6px)));
  }
  44% {
    transform: translateY(calc(-0.38 * var(--amp, 6px)));
  }
  60% {
    transform: translateY(calc(0.22 * var(--amp, 6px)));
  }
  76% {
    transform: translateY(calc(-0.12 * var(--amp, 6px)));
  }
  90% {
    transform: translateY(calc(0.05 * var(--amp, 6px)));
  }
}

/* ================= 북 ================= */
.drum-wrap {
  display: flex;
  justify-content: center;
  padding: 10px;
}

.drum-head {
  position: relative;
  width: 200px;
  height: 200px;
  border-radius: 50%;
  border: 8px solid #8b5a2b;
  background: #6b4423;
  cursor: pointer;
  overflow: hidden;
  padding: 0;
}

.drum-skin {
  position: absolute;
  inset: 6px;
  border-radius: 50%;
  background: radial-gradient(circle at 45% 40%, #fdf6e3, #e7d7b0 70%, #cdb98a);
  transform-origin: center;
}

.drum-skin.hit {
  animation: drum-bounce 0.4s ease-out 1;
}

.drum-skin.hit.hard {
  animation-name: drum-bounce-hard;
}

@keyframes drum-bounce {
  0% {
    transform: scaleY(1);
  }
  30% {
    transform: scaleY(0.92);
  }
  60% {
    transform: scaleY(1.03);
  }
  100% {
    transform: scaleY(1);
  }
}

@keyframes drum-bounce-hard {
  0% {
    transform: scaleY(1);
  }
  25% {
    transform: scaleY(0.82);
  }
  55% {
    transform: scaleY(1.07);
  }
  100% {
    transform: scaleY(1);
  }
}

.drum-ripple {
  position: absolute;
  left: 50%;
  top: 50%;
  width: 40px;
  height: 40px;
  margin: -20px 0 0 -20px;
  border-radius: 50%;
  border: 3px solid rgba(255, 255, 255, 0.8);
  transform: scale(0.2);
  pointer-events: none;
  animation: drum-ripple 0.6s ease-out forwards;
}

.drum-ripple.hard {
  border-color: rgba(255, 209, 102, 0.95);
  border-width: 4px;
}

@keyframes drum-ripple {
  to {
    transform: scale(2.4);
    opacity: 0;
  }
}

.drum-controls {
  display: flex;
  gap: 10px;
}

/* ================= 관악기 ================= */
.wind-wrap {
  display: flex;
  justify-content: center;
  padding: 20px 0;
}

.wind-pipe {
  position: relative;
  width: min(88vw, 460px);
  height: 56px;
  border-radius: 28px;
  background: linear-gradient(180deg, #d7b98f, #a9814f);
  border: 2px solid #7c5a34;
  display: flex;
  align-items: center;
  transition: box-shadow 0.2s ease;
}

.wind-pipe.blowing {
  box-shadow: 0 0 22px 4px rgba(125, 255, 179, 0.55);
}

.wind-mouth {
  position: absolute;
  left: -14px;
  top: 50%;
  width: 20px;
  height: 34px;
  transform: translateY(-50%);
  border-radius: 8px 4px 4px 8px;
  background: #7c5a34;
}

.wind-air {
  position: absolute;
  left: 8px;
  right: 8px;
  top: 50%;
  height: 10px;
  transform: translateY(-50%);
  border-radius: 999px;
  opacity: 0;
  background: repeating-linear-gradient(
    90deg,
    rgba(255, 255, 255, 0.9) 0 8px,
    transparent 8px 22px
  );
  background-size: 44px 100%;
}

.wind-pipe.blowing .wind-air {
  opacity: 0.85;
  animation: wind-flow 0.5s linear infinite;
}

@keyframes wind-flow {
  from {
    background-position: 0 0;
  }
  to {
    background-position: 44px 0;
  }
}

.wind-hole {
  position: relative;
  z-index: 1;
  width: 24px;
  height: 24px;
  margin-left: 10%;
  border-radius: 50%;
  border: 2px solid #5f421f;
  background: #3a2714;
  cursor: pointer;
}

.wind-hole:first-of-type {
  margin-left: 22%;
}

.wind-hole.covered {
  background: radial-gradient(circle at 40% 35%, #ffe3a3, #ef9a5a);
  border-color: #b9722f;
}

.wind-blow-btn {
  font-size: 1rem;
  padding: 10px 32px;
}

@media (prefers-reduced-motion: reduce) {
  .guitar-wire.plucking,
  .drum-skin.hit,
  .drum-ripple,
  .wind-pipe.blowing .wind-air {
    animation: none;
  }
}