* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
  background: linear-gradient(135deg, var(--bg-start) 0%, var(--bg-end) 100%);
  color: var(--text);
  height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  -webkit-app-region: drag;
}

/* Screen Management */
.screen {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  width: 100%;
  height: 100vh;
  overflow-y: auto;
  padding: 20px 0;
}

.screen.hidden {
  display: none;
}

.container {
  text-align: center;
  padding: 20px;
  max-width: 800px;
  width: 100%;
  margin: auto;
}

/* Corner icons - fixed to viewport top right */
.corner-icons {
  position: fixed;
  top: 20px;
  right: 20px;
  display: flex;
  gap: 12px;
  z-index: 1000;
  -webkit-app-region: no-drag;
}

.corner-icon {
  color: var(--icon-color);
  width: 44px;
  height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  transition: all 0.3s ease;
  cursor: pointer;
  text-decoration: none;
  background: var(--icon-bg);
}

button.corner-icon {
  border: none;
  padding: 0;
  font-size: 0;
  background: var(--icon-bg);
  backdrop-filter: none;
}

.corner-icon:hover {
  color: var(--icon-hover-color);
  background: var(--icon-hover-bg);
  transform: scale(1.1);
}

.corner-icon:active {
  transform: scale(0.95);
}

.header {
  margin-bottom: 40px;
}

.header h1 {
  font-size: 2rem;
  font-weight: 300;
  opacity: 0.9;
  margin-bottom: 5px;
}

.key-mode-summary {
  font-size: 1rem;
  font-weight: 300;
  opacity: 0.7;
  margin-top: 5px;
}

.session-timer {
  font-size: 1.2rem;
  font-weight: 400;
  opacity: 0.8;
  margin-top: 10px;
  min-height: 24px;
}

.chord-area {
  background: var(--surface);
  backdrop-filter: blur(10px);
  border-radius: 20px;
  padding: 40px 35px;
  margin-bottom: 25px;
  min-height: 240px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  box-shadow: 0 8px 32px var(--shadow);
  -webkit-app-region: no-drag;
}

.chord-display-container {
  margin-bottom: 20px;
  transition: transform 0.1s ease;
}

/* Chord change pulse animation */
@keyframes chord-pulse {
  0% { transform: scale(1); }
  50% { transform: scale(1.05); }
  100% { transform: scale(1); }
}

.chord-display-container.chord-pulse {
  animation: chord-pulse 200ms ease-out;
}

#chord-display {
  font-size: 5rem;
  font-weight: 700;
  margin-bottom: 10px;
  text-shadow: var(--text-shadow);
}

#chord-display sup,
#session-chord-display sup {
  font-size: 0.6em;
  vertical-align: super;
  line-height: 0;
  opacity: 0.6;
}

#chord-display .chord-quality {
  font-size: 3rem;
  font-weight: 400;
}

#chord-display .chord-subtext,
#session-chord-display .chord-subtext {
  display: block;
  font-size: 2rem;
  font-weight: 300;
  margin-top: 10px;
  opacity: 0.7;
}

#inversion-display,
#session-inversion-display {
  font-size: 1.3rem;
  opacity: 0.8;
  font-weight: 300;
  min-height: 30px;
}

#notes-display {
  font-size: 1.5rem;
  opacity: 0.9;
  margin-top: 20px;
  min-height: 40px;
  font-weight: 300;
}

/* Chord Preview */
.chord-preview {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  margin: 20px 0;
  padding: 15px;
  background: var(--icon-bg);
  border-radius: 10px;
  border: 1px solid var(--surface-border);
}

.chord-preview.hidden {
  visibility: hidden;
}

.chord-preview .preview-label {
  font-size: 0.9rem;
  opacity: 0.7;
  font-weight: 400;
}

.chord-preview #preview-chord-display,
.chord-preview #session-preview-chord-display {
  font-size: 1.8rem;
  font-weight: 500;
  opacity: 0.85;
}

#timer-display {
  font-size: 3rem;
  font-weight: 300;
  opacity: 0.7;
  margin-top: 20px;
}

/* Beat and bar display container */
.beat-bar-container {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 10px;
  margin-top: 20px;
  margin-bottom: 10px;
}

.beat-bar-container.hidden {
  display: none;
}

/* Bar counter (e.g., "Bar 2 of 4") */
.bar-counter {
  font-size: 1.2rem;
  font-weight: 500;
  opacity: 0.8;
  letter-spacing: 0.5px;
}

/* Beat indicators container — wider gap separates beat groups */
.beat-indicators {
  display: flex;
  gap: 24px;
  align-items: center;
}

/* Beat group — keeps dots within a group tightly spaced */
.beat-group {
  display: flex;
  gap: 10px;
  align-items: center;
}

/* Individual beat dot */
.beat-dot {
  width: 20px;
  height: 20px;
  border-radius: 50%;
  border: 2px solid var(--beat-border);
  background: transparent;
  transition: all 0.1s ease;
}

/* Active beat (filled dot) */
.beat-dot.active {
  background: var(--beat-active);
  border-color: var(--beat-active);
  box-shadow: 0 0 15px var(--beat-glow);
  transform: scale(1.2);
}

.controls {
  display: flex;
  gap: 15px;
  justify-content: center;
  flex-wrap: wrap;
  margin-bottom: 20px;
  -webkit-app-region: no-drag;
}

button {
  background: var(--btn-bg);
  border: 2px solid var(--btn-border);
  color: var(--text);
  padding: 15px 30px;
  font-size: 1rem;
  border-radius: 10px;
  cursor: pointer;
  transition: all 0.3s ease;
  font-weight: 500;
  backdrop-filter: blur(10px);
  -webkit-app-region: no-drag;
}

button:hover:not(:disabled) {
  background: var(--btn-hover-bg);
  border-color: var(--btn-hover-border);
  transform: translateY(-2px);
  box-shadow: 0 4px 12px var(--shadow);
}

button:active:not(:disabled) {
  transform: translateY(0);
}

button:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

button.active {
  background: var(--btn-active-bg);
  border-color: var(--btn-active-border);
}

button.hidden {
  display: none;
}

.secondary-controls {
  display: flex;
  gap: 15px;
  justify-content: center;
  flex-wrap: wrap;
  -webkit-app-region: no-drag;
}

/* Keyboard shortcuts hint */
.keyboard-shortcuts-hint {
  margin-top: 20px;
  font-size: 0.8rem;
  opacity: 0.45;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  flex-wrap: wrap;
  -webkit-app-region: no-drag;
}

.keyboard-shortcuts-hint kbd {
  display: inline-block;
  padding: 2px 6px;
  font-size: 0.75rem;
  font-family: inherit;
  background: var(--icon-bg);
  border: 1px solid var(--surface-border);
  border-radius: 4px;
  margin-right: 3px;
  line-height: 1.4;
}

/* Mode Selection */
.mode-buttons {
  display: flex;
  flex-direction: column;
  gap: 20px;
  max-width: 400px;
  margin: 0 auto;
  -webkit-app-region: no-drag;
}

.mode-button {
  padding: 30px 40px;
  font-size: 1.3rem;
  min-width: 300px;
}

/* Planned Features Link */
.planned-features-link-container {
  text-align: center;
  margin-top: 30px;
}

.planned-features-link {
  color: var(--icon-color);
  font-size: 0.9rem;
  text-decoration: none;
  padding: 8px 15px;
  border-radius: 6px;
  transition: all 0.3s ease;
  display: inline-block;
  cursor: pointer;
  -webkit-app-region: no-drag;
}

.planned-features-link:hover {
  color: var(--icon-hover-color);
  background: var(--surface);
  transform: translateY(-2px);
  text-decoration: underline;
}

/* Structured Practice */
.session-info {
  font-size: 1rem;
  font-weight: 300;
  opacity: 0.7;
  margin-top: 5px;
}

.session-next-key {
  font-size: 0.9rem;
  opacity: 0.6;
  font-weight: 400;
  margin-top: 5px;
}

.session-next-key.hidden {
  visibility: hidden;
}

/* Key progress bar */
.key-progress-bar {
  width: 80%;
  max-width: 500px;
  height: 4px;
  background: var(--surface);
  border-radius: 2px;
  margin: 12px auto 0;
  overflow: hidden;
}

.key-progress-bar.hidden {
  visibility: hidden;
}

.key-progress-fill {
  height: 100%;
  width: 0%;
  background: var(--btn-active-bg);
  border-radius: 2px;
  transition: width 1s linear;
}

#session-chord-display,
#session-inversion-display,
#session-notes-display,
#session-timer-display {
  font-size: 5rem;
  font-weight: 700;
  margin-bottom: 10px;
  text-shadow: var(--text-shadow);
}

#session-chord-display .chord-quality {
  font-size: 3rem;
  font-weight: 400;
}

#session-inversion-display {
  font-size: 1.3rem;
  opacity: 0.8;
  font-weight: 300;
  min-height: 30px;
}

#session-notes-display {
  font-size: 1.5rem;
  opacity: 0.9;
  margin-top: 20px;
  min-height: 40px;
  font-weight: 300;
}

#session-timer-display {
  font-size: 2rem;
  font-weight: 400;
  opacity: 0.8;
  margin-top: 20px;
}

.session-progress {
  font-size: 1.1rem;
  opacity: 0.8;
  margin-top: 10px;
  min-height: 20px;
  font-weight: 400;
}

/* Congratulations Screen */
.congrats-content {
  text-align: center;
}

.congrats-message {
  font-size: 2.5rem;
  font-weight: 300;
  margin-bottom: 20px;
}

.congrats-stats {
  font-size: 1.2rem;
  opacity: 0.8;
  margin-bottom: 40px;
  line-height: 1.6;
}

/* Modal overlays for feedback and donate */
.modal-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: var(--modal-backdrop);
  backdrop-filter: blur(5px);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 2000;
  -webkit-app-region: no-drag;
}

.modal-overlay.hidden {
  display: none;
}

.modal-content {
  background: var(--modal-surface);
  backdrop-filter: blur(20px);
  border-radius: 20px;
  padding: 40px;
  max-width: 500px;
  max-height: 80vh;
  width: 90%;
  overflow-y: auto;
  box-shadow: 0 8px 32px var(--shadow-heavy);
  border: 1px solid var(--surface-border);
  text-align: center;
}

.modal-content h2 {
  font-size: 2rem;
  font-weight: 300;
  margin-bottom: 20px;
  opacity: 0.95;
}

.modal-content p {
  font-size: 1.1rem;
  opacity: 0.8;
  margin-bottom: 30px;
  line-height: 1.5;
}

.planned-features-list {
  list-style: none;
  padding: 0;
  margin: 0 0 30px 0;
  text-align: left;
}

.planned-features-list li {
  padding: 12px 20px;
  margin-bottom: 10px;
  background: var(--icon-bg);
  border-radius: 8px;
  border-left: 3px solid var(--accent-border);
  font-size: 1rem;
  line-height: 1.4;
  transition: all 0.2s ease;
}

.planned-features-list li:hover {
  background: var(--surface);
  border-left-color: var(--accent);
  transform: translateX(5px);
}

.planned-features-list li::before {
  content: "→";
  margin-right: 10px;
  color: var(--accent);
  font-weight: bold;
}

.modal-donate-link {
  color: var(--text);
  text-decoration: underline;
  cursor: pointer;
  transition: all 0.2s ease;
  -webkit-app-region: no-drag;
}

.modal-donate-link:hover {
  background: var(--surface-hover);
  padding: 2px 6px;
  border-radius: 3px;
}

.contact-links {
  display: flex;
  flex-direction: column;
  gap: 15px;
  margin-bottom: 30px;
}

.contact-link {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 15px 20px;
  background: var(--surface);
  border: 1px solid var(--surface-border);
  border-radius: 12px;
  color: var(--text);
  text-decoration: none;
  font-size: 1.1rem;
  transition: all 0.3s ease;
  cursor: pointer;
}

.contact-link:hover {
  background: var(--surface-hover);
  border-color: var(--btn-hover-border);
  transform: translateX(5px);
}

.contact-link svg {
  flex-shrink: 0;
}

.modal-close-btn {
  background: var(--btn-bg);
  border: 2px solid var(--btn-border);
  color: var(--text);
  padding: 12px 30px;
  font-size: 1rem;
  border-radius: 10px;
  cursor: pointer;
  transition: all 0.3s ease;
  font-weight: 500;
}

/* Help modal sections */
.help-modal-content h3 {
  font-size: 1.3rem;
  font-weight: 500;
  margin-bottom: 8px;
  opacity: 0.95;
}

.help-section {
  text-align: left;
  margin-bottom: 20px;
  padding: 15px 20px;
  background: var(--icon-bg);
  border-radius: 10px;
  border-left: 3px solid var(--accent-border);
}

.help-section p {
  font-size: 1rem;
  margin-bottom: 0;
  line-height: 1.5;
}

/* Custom Alert Modal */
.alert-modal-content {
  max-width: 450px;
  text-align: center;
}

.alert-modal-content h2 {
  color: var(--danger-text);
  margin-bottom: 20px;
}

.alert-modal-content p {
  font-size: 1.1rem;
  margin-bottom: 25px;
}

.modal-close-btn:hover {
  background: var(--btn-hover-bg);
  border-color: var(--btn-hover-border);
  transform: translateY(-2px);
}

/* Donation Toast */
.donation-toast {
  position: fixed;
  bottom: -80px;
  left: 0;
  right: 0;
  width: fit-content;
  margin: 0 auto;
  background: var(--surface);
  backdrop-filter: blur(20px);
  border: 1px solid var(--surface-border);
  border-radius: 14px;
  padding: 14px 20px;
  display: flex;
  align-items: center;
  gap: 14px;
  z-index: 1500;
  box-shadow: 0 8px 32px var(--shadow-heavy);
  transition: bottom 0.4s ease;
  -webkit-app-region: no-drag;
}

.donation-toast.hidden {
  display: none;
}

.donation-toast.visible {
  bottom: 30px;
}

.donation-toast-message {
  font-size: 0.95rem;
  color: var(--text);
  white-space: nowrap;
}

.donation-toast-link {
  color: var(--text);
  font-weight: 600;
  text-decoration: underline;
  cursor: pointer;
  -webkit-app-region: no-drag;
}

.donation-toast-link:hover {
  opacity: 0.85;
}

.donation-toast-dismiss {
  background: none;
  border: none;
  color: var(--icon-color);
  font-size: 1.3rem;
  cursor: pointer;
  padding: 0 4px;
  line-height: 1;
  transition: color 0.2s ease;
  backdrop-filter: none;
}

.donation-toast-dismiss:hover {
  color: var(--text);
  background: none;
  border: none;
  transform: none;
  box-shadow: none;
}

@media (max-width: 768px) {
  #chord-display {
    font-size: 3.5rem;
  }

  #inversion-display {
    font-size: 1.5rem;
  }

  #notes-display {
    font-size: 1.2rem;
  }

  #timer-display {
    font-size: 2rem;
  }

  .chord-area {
    padding: 60px 20px;
  }
}

/* Compact mode for smaller window heights */
@media (max-height: 800px) {
  .header {
    margin-bottom: 20px;
  }

  .header h1 {
    font-size: 1.5rem;
  }

  .key-mode-summary, .session-info {
    font-size: 0.9rem;
  }

  .chord-area {
    padding: 40px 30px;
    min-height: 250px;
    margin-bottom: 20px;
  }

  #chord-display, #session-chord-display {
    font-size: 4rem;
  }

  #chord-display sup {
    font-size: 0.6em;
  }

  #chord-display .chord-quality, #session-chord-display .chord-quality {
    font-size: 2.5rem;
  }

  #chord-display .chord-subtext,
  #session-chord-display .chord-subtext {
    font-size: 1.5rem;
  }

  #inversion-display, #session-inversion-display {
    font-size: 1.1rem;
  }

  #timer-display {
    font-size: 2.5rem;
    margin-top: 15px;
  }

  #session-timer-display {
    font-size: 1.5rem;
    margin-top: 15px;
  }

  .session-progress {
    font-size: 0.95rem;
  }

  .controls {
    margin-bottom: 15px;
  }

  button {
    padding: 12px 24px;
    font-size: 0.95rem;
  }

  .congrats-message {
    font-size: 2rem;
  }
}