:root {
    --bg-deep: #0a0a0f;
    --bg-card: #12121a;
    --bg-card-hover: #1a1a26;
    --accent-warm: #e8a84c;
    --accent-warm-dim: #b8843a;
    --accent-cool: #6b8aaf;
    --text-primary: #eae6df;
    --text-secondary: #8a8692;
    --text-muted: #5a5666;
    --border-subtle: rgba(234, 230, 223, 0.06);
    --border-accent: rgba(232, 168, 76, 0.25);
    --glow-warm: rgba(232, 168, 76, 0.08);
    --glow-cool: rgba(107, 138, 175, 0.06);
  }

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

  body {
    font-family: 'Instrument Sans', sans-serif;
    background: var(--bg-deep);
    color: var(--text-primary);
    min-height: 100vh;
    overflow-x: hidden;
  }

  /* Ambient background */
  body::before {
    content: '';
    position: fixed;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background:
      radial-gradient(ellipse at 20% 50%, rgba(232, 168, 76, 0.03) 0%, transparent 50%),
      radial-gradient(ellipse at 80% 20%, rgba(107, 138, 175, 0.03) 0%, transparent 50%),
      radial-gradient(ellipse at 50% 80%, rgba(160, 100, 180, 0.02) 0%, transparent 50%);
    z-index: 0;
    pointer-events: none;
  }

  .app-container {
    position: relative;
    z-index: 1;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 5rem 2rem 2rem;
  }

  /* ---- HEADER ---- */
  .app-header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 100;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1.25rem 2rem;
    backdrop-filter: blur(20px);
    background: rgba(10, 10, 15, 0.7);
    border-bottom: 1px solid var(--border-subtle);
  }

  .exit-btn {
    display: inline-flex;
    align-items: center;
    gap: 0.3rem;
    background: none;
    border: 1px solid var(--border-subtle);
    color: var(--text-secondary);
    padding: 0.4rem 0.9rem;
    border-radius: 8px;
    font-size: 0.85rem;
    font-weight: 500;
    font-family: inherit;
    cursor: pointer;
    transition: all 0.2s;
  }

  .exit-btn:hover {
    color: var(--text-primary);
    border-color: rgba(234, 230, 223, 0.2);
    background: rgba(234, 230, 223, 0.05);
  }

  .logo {
    font-family: 'DM Serif Display', serif;
    font-size: 1.35rem;
    color: var(--text-primary);
    letter-spacing: -0.01em;
  }

  .logo span {
    color: var(--accent-warm);
  }

  /* ---- LOGIN STYLES REMOVED ---- */

  /* ---- PRACTICE SCREEN ---- */
  .practice-screen {
    text-align: center;
    width: 100%;
    max-width: 560px;
    animation: fadeUp 0.6s ease-out;
  }

  .start-section {
    margin-top: 2rem;
  }

  .start-btn {
    position: relative;
    display: inline-flex;
    align-items: center;
    gap: 0.75rem;
    background: linear-gradient(135deg, var(--accent-warm), var(--accent-warm-dim));
    color: var(--bg-deep);
    border: none;
    padding: 1.1rem 2.8rem;
    border-radius: 16px;
    font-size: 1.1rem;
    font-weight: 700;
    font-family: inherit;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 4px 30px rgba(232, 168, 76, 0.2);
    letter-spacing: 0.01em;
  }

  .start-btn:hover {
    transform: translateY(-2px) scale(1.02);
    box-shadow: 0 8px 40px rgba(232, 168, 76, 0.35);
  }

  .start-btn.active {
    background: linear-gradient(135deg, var(--accent-warm), var(--accent-warm-dim));
    box-shadow: 0 4px 30px rgba(232, 168, 76, 0.2);
  }

  .start-btn.active:hover {
    box-shadow: 0 8px 40px rgba(232, 168, 76, 0.35);
  }

  .practice-controls {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.75rem;
    margin-top: 0.75rem;
  }

  .pause-btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    background: transparent;
    color: var(--accent-warm);
    border: 1.5px solid var(--accent-warm);
    padding: 1.1rem 2.2rem;
    border-radius: 16px;
    font-size: 1.05rem;
    font-weight: 600;
    font-family: inherit;
    cursor: pointer;
    transition: all 0.3s ease;
  }

  .pause-btn:hover {
    background: rgba(232, 168, 76, 0.08);
    transform: translateY(-1px);
  }

  .pause-btn.paused {
    color: #5cb87a;
    border-color: #5cb87a;
  }

  .pause-btn.paused:hover {
    background: rgba(92, 184, 122, 0.08);
  }

  .change-btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    background: transparent;
    color: var(--accent-cool);
    border: 1.5px solid var(--accent-cool);
    padding: 1.1rem 2.2rem;
    border-radius: 16px;
    font-size: 1.05rem;
    font-weight: 600;
    font-family: inherit;
    cursor: pointer;
    transition: all 0.3s ease;
  }

  .change-btn:hover {
    background: rgba(107, 138, 175, 0.1);
    transform: translateY(-2px);
    box-shadow: 0 6px 30px rgba(107, 138, 175, 0.15);
  }

  .practice-hint {
    color: var(--text-muted);
    font-size: 0.85rem;
    margin-top: 1rem;
  }

  /* ---- EXERCISE DISPLAY ---- */
  .exercise-display {
    margin-top: 2.5rem;
    animation: fadeUp 0.5s ease-out;
  }

  .key-display {
    margin-bottom: 2rem;
    display: flex;
    flex-direction: column;
    align-items: center;
  }

  .key-label {
    font-size: 0.8rem;
    text-transform: uppercase;
    letter-spacing: 0.15em;
    color: var(--text-muted);
    margin-bottom: 1rem;
    font-weight: 600;
  }

  .circle-of-fifths {
    position: relative;
    width: 300px;
    height: 300px;
  }

  .circle-of-fifths svg {
    width: 100%;
    height: 100%;
  }

  .cof-segment {
    fill: transparent;
    stroke: var(--border-subtle);
    stroke-width: 1;
    cursor: default;
    transition: fill 0.4s ease, stroke 0.4s ease;
  }

  .circle-of-fifths.interactive .cof-segment {
    cursor: pointer;
  }

  .circle-of-fifths.interactive .cof-segment:not(.active):not(.upcoming):hover {
    fill: rgba(255, 255, 255, 0.06);
    stroke: rgba(234, 230, 223, 0.4);
  }

  .cof-segment.active {
    fill: rgba(232, 168, 76, 0.12);
    stroke: var(--accent-warm);
    stroke-width: 2;
  }

  .cof-segment.upcoming {
    fill: rgba(107, 138, 175, 0.12);
    stroke: var(--accent-cool);
    stroke-width: 2;
    animation: upcomingPulse 1s ease-in-out infinite;
  }

  .cof-label {
    font-family: 'DM Serif Display', serif;
    font-size: 14px;
    fill: var(--text-muted);
    text-anchor: middle;
    dominant-baseline: central;
    transition: fill 0.4s ease, font-size 0.3s ease;
    pointer-events: none;
  }

  .cof-label.active {
    fill: var(--accent-warm);
    font-size: 20px;
    filter: drop-shadow(0 0 12px rgba(232, 168, 76, 0.4));
  }

  .cof-label.upcoming {
    fill: var(--accent-cool);
    font-size: 17px;
    filter: drop-shadow(0 0 10px rgba(107, 138, 175, 0.4));
  }

  .cof-center-note {
    font-family: 'DM Serif Display', serif;
    font-size: 36px;
    fill: var(--accent-warm);
    text-anchor: middle;
    dominant-baseline: central;
    filter: drop-shadow(0 0 20px rgba(232, 168, 76, 0.3));
  }

  .exercise-details {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
    margin-top: 1.5rem;
  }

  .detail-card {
    background: var(--bg-card);
    border: 1px solid var(--border-subtle);
    border-radius: 14px;
    padding: 1.2rem 1.8rem;
    min-width: 200px;
    flex: 1;
    max-width: 260px;
    transition: all 0.3s;
  }

  .detail-card:hover {
    background: var(--bg-card-hover);
    border-color: var(--border-accent);
  }

  .detail-label {
    font-size: 0.7rem;
    text-transform: uppercase;
    letter-spacing: 0.15em;
    color: var(--text-muted);
    margin-bottom: 0.5rem;
    font-weight: 600;
    display: flex;
    align-items: center;
    justify-content: space-between;
  }

  .detail-value {
    font-size: 1.15rem;
    font-weight: 600;
    color: var(--text-primary);
  }

  .detail-value.direction {
    color: var(--accent-cool);
  }

  .detail-value.method {
    color: #b89ae0;
  }

  @keyframes upcomingHintPulse {
    0%, 100% { opacity: 0.4; }
    50%       { opacity: 1; }
  }

  .upcoming-hint {
    font-size: 0.85rem;
    line-height: 1;
    opacity: 0;
    text-transform: none;
    letter-spacing: 0;
  }

  .upcoming-hint.visible {
    animation: upcomingHintPulse 1s ease-in-out infinite;
  }

  .upcoming-hint.direction-hint { color: var(--accent-cool); }
  .upcoming-hint.method-hint    { color: #b89ae0; }

  /* Drone indicator */
  .drone-indicator {
    margin-top: 2rem;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.6rem;
    color: var(--text-secondary);
    font-size: 0.85rem;
  }

  .drone-dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--accent-warm);
    animation: dronePulse 1.5s ease-in-out infinite;
  }

  /* ---- ANIMATIONS ---- */
  @keyframes fadeUp {
    from { opacity: 0; transform: translateY(16px); }
    to { opacity: 1; transform: translateY(0); }
  }

  @keyframes dronePulse {
    0%, 100% { opacity: 0.4; transform: scale(1); }
    50% { opacity: 1; transform: scale(1.4); }
  }

  @keyframes upcomingPulse {
    0%, 100% { fill: rgba(107, 138, 175, 0.08); }
    50% { fill: rgba(107, 138, 175, 0.2); }
  }

  /* ---- VISUALIZER ---- */
  .visualizer {
    display: flex;
    align-items: flex-end;
    justify-content: center;
    gap: 3px;
    height: 40px;
    margin-top: 1.5rem;
  }

  .visualizer .bar {
    width: 3px;
    background: var(--accent-warm);
    border-radius: 2px;
    opacity: 0.5;
    animation: barPulse 1.2s ease-in-out infinite;
  }

  @keyframes barPulse {
    0%, 100% { height: 8px; opacity: 0.3; }
    50% { height: 28px; opacity: 0.7; }
  }

  /* ---- AUTO CHANGE ---- */
  .auto-change-row {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.6rem;
    margin-top: 1.25rem;
    flex-wrap: wrap;
  }

  .auto-change-label {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.9rem;
    color: var(--text-secondary);
    cursor: pointer;
    user-select: none;
    position: relative;
  }

  .auto-check {
    display: none;
  }

  .checkmark {
    width: 18px;
    height: 18px;
    border-radius: 5px;
    border: 1.5px solid var(--text-muted);
    background: transparent;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    transition: all 0.2s;
    flex-shrink: 0;
  }

  .checkmark::after {
    content: '';
    width: 10px;
    height: 10px;
    border-radius: 2px;
    background: var(--accent-warm);
    transform: scale(0);
    transition: transform 0.15s ease;
  }

  .auto-check:checked + .checkmark {
    border-color: var(--accent-warm);
  }

  .auto-check:checked + .checkmark::after {
    transform: scale(1);
  }

  .auto-select {
    background: var(--bg-card);
    color: var(--text-primary);
    border: 1.5px solid var(--border-subtle);
    border-radius: 8px;
    padding: 0.4rem 0.6rem;
    font-size: 0.9rem;
    font-family: inherit;
    cursor: pointer;
    transition: border-color 0.2s;
    appearance: auto;
  }

  .auto-select:hover,
  .auto-select:focus {
    border-color: var(--border-accent);
    outline: none;
  }

  .drone-type-label {
    font-size: 0.9rem;
    color: var(--text-secondary);
  }

  .bpm-label {
    font-size: 0.9rem;
    color: var(--text-secondary);
  }

  .countdown-badge {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    background: rgba(232, 168, 76, 0.08);
    border: 1px solid var(--border-accent);
    border-radius: 20px;
    padding: 0.3rem 0.8rem;
    font-size: 0.8rem;
    color: var(--accent-warm);
    font-weight: 600;
    margin-top: 0.75rem;
    font-variant-numeric: tabular-nums;
  }

  .countdown-badge.countdown-hidden {
    visibility: hidden;
  }

  /* ---- SETTINGS ---- */
  .settings-section {
    margin-top: 2.5rem;
    padding-top: 1.5rem;
    border-top: 1px solid var(--border-subtle);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.75rem;
    width: 100%;
  }

  .hidden { display: none !important; }

  @media (max-width: 600px) {
    .circle-of-fifths { width: 260px; height: 260px; }
    .exercise-details { flex-direction: column; align-items: center; }
    .detail-card { max-width: 100%; width: 100%; }
    .start-section { display: flex; flex-direction: column; align-items: center; gap: 0.75rem; }
    .practice-controls { flex-direction: column; }
    .app-header { padding: 1rem; }
  }