* { box-sizing: border-box; -webkit-tap-highlight-color: transparent; }

html, body {
  margin: 0;
  padding: 0;
  background: #14181f;
  color: #eef1f5;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  height: 100%;
  overscroll-behavior: none;
}

#app {
  max-width: 480px;
  margin: 0 auto;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

#topbar {
  padding: 10px 14px 6px;
}

#title {
  font-size: 1.3rem;
  font-weight: 700;
  margin-bottom: 4px;
}

#stats {
  display: flex;
  justify-content: space-between;
  font-size: 0.75rem;
  color: #9aa4b2;
}

main {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 8px 12px;
}

#modeRow {
  display: flex;
  gap: 8px;
  width: 100%;
  margin-top: 4px;
}

.modeBtn {
  flex: 1;
  padding: 9px 0;
  border-radius: 8px;
  border: 1px solid #2a2f3a;
  background: #1b2029;
  color: #9aa4b2;
  font-size: 0.85rem;
  font-weight: 600;
}

.modeBtn.active {
  background: #4c7dff;
  color: #fff;
  border-color: #4c7dff;
}

.modeBtn:disabled {
  opacity: 0.55;
}

#clefRow {
  width: 100%;
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  margin: 6px 0 2px;
}

#clefLabel {
  font-size: 0.95rem;
  color: #9aa4b2;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

#questionCounter {
  font-size: 0.8rem;
  color: #6b7280;
  font-weight: 600;
}

#staffWrap {
  position: relative;
  width: 100%;
  background: #fff;
  border-radius: 12px;
  padding: 10px 4px;
  display: flex;
  justify-content: center;
  overflow: hidden;
}

#pausedOverlay {
  display: none;
  position: absolute;
  inset: 0;
  background: rgba(20, 24, 31, 0.78);
  color: #fff;
  font-size: 1.4rem;
  font-weight: 700;
  align-items: center;
  justify-content: center;
  border-radius: 12px;
}

#pausedOverlay.show {
  display: flex;
}

#staff svg {
  max-width: 100%;
}

#timerRow {
  width: 100%;
  display: flex;
  align-items: center;
  gap: 10px;
  margin: 14px 0 6px;
}

#timerBar {
  flex: 1;
  height: 10px;
  border-radius: 6px;
  background: #2a2f3a;
  overflow: hidden;
}

#timerFill {
  height: 100%;
  width: 100%;
  background: #4cd17a;
  transition: width 0.1s linear, background 0.2s;
}

#timerNum {
  width: 28px;
  text-align: right;
  font-size: 1.1rem;
  font-weight: 700;
  font-variant-numeric: tabular-nums;
}

#feedback {
  min-height: 1.6rem;
  font-size: 1.05rem;
  font-weight: 700;
  margin: 4px 0;
}

#feedback.correct { color: #4cd17a; }
#feedback.wrong { color: #ff5c5c; }
#feedback.timeout { color: #ffb84c; }

#answers {
  position: relative;
  display: flex;
  width: 100%;
  height: 108px;
  margin-top: auto;
  margin-bottom: 14px;
}

.whiteKey {
  flex: 1;
  position: relative;
  z-index: 1;
  background: #f5f6f8;
  border: 1px solid #cfd3da;
  border-left-width: 0;
  border-radius: 0 0 8px 8px;
  color: #2a2f3a;
  display: flex;
  align-items: flex-end;
  justify-content: center;
  padding-bottom: 8px;
  font-size: 0.85rem;
  font-weight: 700;
  touch-action: manipulation;
}

.whiteKey:first-child {
  border-left-width: 1px;
  border-top-left-radius: 6px;
}

.whiteKey:last-child {
  border-top-right-radius: 6px;
}

.whiteKey:active {
  background: #e2e5ec;
}

.whiteKey.correctFlash {
  background: #4cd17a !important;
  color: #14181f;
}

.whiteKey.wrongFlash {
  background: #ff5c5c !important;
  color: #14181f;
}

.blackKey {
  position: absolute;
  top: 0;
  height: 62%;
  z-index: 2;
  background: #20242e;
  border-radius: 0 0 5px 5px;
  pointer-events: none;
}

footer {
  display: flex;
  gap: 10px;
  padding: 10px 14px calc(22px + env(safe-area-inset-bottom));
}

footer button {
  flex: 1;
  padding: 12px 0;
  border-radius: 10px;
  border: none;
  font-size: 1rem;
  font-weight: 600;
}

#startBtn {
  background: #4c7dff;
  color: #fff;
}

#pauseBtn {
  background: #2a2f3a;
  color: #eef1f5;
}

#pauseBtn:disabled {
  opacity: 0.5;
}

#resetStatsBtn {
  background: #232936;
  color: #9aa4b2;
}

#summaryOverlay {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(10, 12, 16, 0.88);
  align-items: center;
  justify-content: center;
  padding: 20px;
  z-index: 10;
}

#summaryOverlay.show {
  display: flex;
}

#summaryCard {
  width: 100%;
  max-width: 360px;
  background: #1b2029;
  border-radius: 16px;
  padding: 24px 22px;
  text-align: center;
}

#summaryTitle {
  font-size: 1.05rem;
  color: #9aa4b2;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  margin-bottom: 10px;
}

#summaryScore {
  font-size: 2.6rem;
  font-weight: 800;
  color: #4c7dff;
  margin-bottom: 16px;
}

#summaryRow {
  display: flex;
  justify-content: space-between;
  font-size: 0.95rem;
  padding: 8px 0;
  border-top: 1px solid #2a2f3a;
  color: #d3d8e0;
}

#summaryImprovement {
  margin-top: 14px;
  min-height: 1.4rem;
  font-size: 0.9rem;
  font-weight: 600;
  color: #4cd17a;
}

#summaryThanks {
  margin-top: 14px;
  font-size: 0.95rem;
  color: #9aa4b2;
}

#summaryBtnRow {
  margin-top: 18px;
  display: flex;
  gap: 10px;
}

#summaryBtnRow button {
  flex: 1;
  padding: 13px 0;
  border-radius: 10px;
  border: none;
  font-size: 1rem;
  font-weight: 700;
}

#playAgainBtn {
  background: #4c7dff;
  color: #fff;
}

#homeBtn {
  background: #2a2f3a;
  color: #eef1f5;
}