/* ═══════════════════════════════════════════════════════════════
   TYPEFLOW — CSS
   ═══════════════════════════════════════════════════════════════ */

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

:root {
  --bg-primary: #1a1a2e;
  --bg-secondary: #16213e;
  --bg-card: #1e2a4a;
  --bg-card-hover: #243356;
  --bg-input: #0f1629;
  --text-primary: #e2e8f0;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;
  --accent: #6c63ff;
  --accent-glow: rgba(108, 99, 255, 0.3);
  --accent-secondary: #00d2ff;
  --success: #22c55e;
  --success-glow: rgba(34, 197, 94, 0.3);
  --error: #ef4444;
  --error-glow: rgba(239, 68, 68, 0.3);
  --warning: #f59e0b;
  --border: rgba(255,255,255,0.06);
  --radius: 12px;
  --radius-sm: 8px;
  --radius-lg: 16px;
  --shadow: 0 4px 24px rgba(0,0,0,0.3);
  --transition: 0.2s ease;
  --font-mono: 'JetBrains Mono', 'Fira Code', 'Cascadia Code', 'Consolas', monospace;
  --font-sans: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --finger-thumb: #f59e0b;
  --finger-index: #6c63ff;
  --finger-middle: #22c55e;
  --finger-ring: #00d2ff;
  --finger-pinky: #ef4444;
}

html { font-size: 16px; }
body {
  font-family: var(--font-sans);
  background: var(--bg-primary);
  color: var(--text-primary);
  min-height: 100vh;
  overflow-x: hidden;
  line-height: 1.6;
}

.hidden { display: none !important; }

::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: var(--bg-primary); }
::-webkit-scrollbar-thumb { background: var(--bg-card); border-radius: 3px; }
::-webkit-scrollbar-thumb:hover { background: var(--accent); }

#app {
  max-width: 1100px;
  margin: 0 auto;
  padding: 24px 20px;
  min-height: 100vh;
}

/* --- Header / Nav --- */
.app-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 0;
  margin-bottom: 32px;
  border-bottom: 1px solid var(--border);
}
.app-logo {
  font-family: var(--font-mono);
  font-size: 1.5rem;
  font-weight: 700;
  background: linear-gradient(135deg, var(--accent), var(--accent-secondary));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  cursor: pointer;
  letter-spacing: -0.5px;
}
.app-logo span { opacity: 0.5; font-weight: 400; }
.nav-links { display: flex; gap: 4px; }
.nav-link {
  padding: 8px 16px;
  border-radius: var(--radius-sm);
  color: var(--text-secondary);
  cursor: pointer;
  font-size: 0.875rem;
  font-weight: 500;
  transition: var(--transition);
  border: none;
  background: none;
  font-family: var(--font-sans);
}
.nav-link:hover { color: var(--text-primary); background: var(--bg-card); }
.nav-link.active { color: var(--accent); background: var(--accent-glow); }
.user-level {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 6px 14px;
  border-radius: 20px;
  background: var(--bg-card);
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--accent);
  border: 1px solid var(--border);
}
.user-level .xp-bar {
  width: 60px; height: 4px;
  background: var(--bg-input);
  border-radius: 2px;
  overflow: hidden;
}
.user-level .xp-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--accent), var(--accent-secondary));
  border-radius: 2px;
  transition: width 0.5s ease;
}

/* --- Page Titles --- */
.page-title { font-size: 1.75rem; font-weight: 700; margin-bottom: 8px; letter-spacing: -0.5px; }
.page-subtitle { color: var(--text-secondary); font-size: 0.95rem; margin-bottom: 32px; }

/* --- Stats Grid --- */
.stats-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; margin-bottom: 32px; }
.stat-card {
  background: var(--bg-card);
  border-radius: var(--radius);
  padding: 20px;
  border: 1px solid var(--border);
  transition: var(--transition);
}
.stat-card:hover { border-color: var(--accent); transform: translateY(-2px); }
.stat-label { font-size: 0.75rem; text-transform: uppercase; letter-spacing: 1px; color: var(--text-muted); margin-bottom: 8px; }
.stat-value { font-family: var(--font-mono); font-size: 1.75rem; font-weight: 700; }
.stat-value.accent { color: var(--accent); }
.stat-value.success { color: var(--success); }
.stat-value.warning { color: var(--warning); }
.stat-value.secondary { color: var(--accent-secondary); }
.stat-unit { font-size: 0.85rem; color: var(--text-muted); font-weight: 400; }

/* --- Quick Actions --- */
.quick-actions { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; margin-bottom: 32px; }
.quick-action {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  cursor: pointer;
  transition: var(--transition);
  text-align: center;
}
.quick-action:hover { border-color: var(--accent); background: var(--bg-card-hover); transform: translateY(-2px); }
.quick-action .icon { font-size: 2rem; margin-bottom: 12px; }
.quick-action .label { font-weight: 600; margin-bottom: 4px; }
.quick-action .desc { font-size: 0.8rem; color: var(--text-muted); }

/* --- Chart --- */
.chart-section { background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius); padding: 24px; margin-bottom: 32px; }
.chart-section h3 { margin-bottom: 16px; font-size: 1rem; }
.chart-container { width: 100%; height: 200px; position: relative; }
canvas.chart { width: 100% !important; height: 100% !important; }

/* --- Lessons --- */
.lessons-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(300px, 1fr)); gap: 16px; }
.lesson-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  cursor: pointer;
  transition: var(--transition);
  position: relative;
  overflow: hidden;
}
.lesson-card::before {
  content: '';
  position: absolute;
  top: 0; left: 0;
  width: 100%; height: 3px;
  background: linear-gradient(90deg, var(--accent), var(--accent-secondary));
  opacity: 0;
  transition: var(--transition);
}
.lesson-card:hover::before { opacity: 1; }
.lesson-card:hover { border-color: var(--accent); transform: translateY(-2px); }
.lesson-card.locked { opacity: 0.45; cursor: not-allowed; pointer-events: none; }
.lesson-card.completed { border-color: var(--success); }
.lesson-card.completed::before { background: var(--success); opacity: 1; }
.lesson-number { font-family: var(--font-mono); font-size: 0.7rem; color: var(--text-muted); text-transform: uppercase; letter-spacing: 1.5px; margin-bottom: 8px; }
.lesson-title { font-weight: 700; font-size: 1.1rem; margin-bottom: 4px; }
.lesson-keys { font-family: var(--font-mono); color: var(--accent); font-size: 0.85rem; margin-bottom: 12px; }
.lesson-desc { font-size: 0.8rem; color: var(--text-secondary); margin-bottom: 16px; }
.lesson-progress-bar { width: 100%; height: 4px; background: var(--bg-input); border-radius: 2px; overflow: hidden; }
.lesson-progress-fill { height: 100%; background: linear-gradient(90deg, var(--accent), var(--accent-secondary)); border-radius: 2px; transition: width 0.4s ease; }
.lesson-card.completed .lesson-progress-fill { background: var(--success); }
.lesson-meta { display: flex; justify-content: space-between; align-items: center; margin-top: 8px; font-size: 0.75rem; color: var(--text-muted); }
.lesson-badge { padding: 2px 10px; border-radius: 10px; font-size: 0.7rem; font-weight: 600; text-transform: uppercase; letter-spacing: 0.5px; }
.badge-new { background: var(--accent-glow); color: var(--accent); }
.badge-done { background: var(--success-glow); color: var(--success); }
.badge-locked { background: rgba(100,116,139,0.2); color: var(--text-muted); }

/* --- Exercise --- */
.exercise-header { display: flex; justify-content: space-between; align-items: center; margin-bottom: 24px; }
.exercise-title { font-size: 1.1rem; font-weight: 600; }
.exercise-controls { display: flex; gap: 8px; align-items: center; }
.btn {
  padding: 8px 18px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
  background: var(--bg-card);
  color: var(--text-primary);
  cursor: pointer;
  font-size: 0.85rem;
  font-weight: 500;
  transition: var(--transition);
  font-family: var(--font-sans);
}
.btn:hover { border-color: var(--accent); background: var(--bg-card-hover); }
.btn-primary { background: var(--accent); border-color: var(--accent); color: #fff; }
.btn-primary:hover { background: #5b53e0; }
.btn-sm { padding: 6px 12px; font-size: 0.8rem; }

.live-stats { display: flex; gap: 24px; justify-content: center; margin-bottom: 24px; padding: 16px; background: var(--bg-card); border-radius: var(--radius); border: 1px solid var(--border); }
.live-stat { text-align: center; }
.live-stat-value { font-family: var(--font-mono); font-size: 1.5rem; font-weight: 700; }
.live-stat-label { font-size: 0.7rem; text-transform: uppercase; letter-spacing: 1px; color: var(--text-muted); }
.timer-display { color: var(--accent-secondary); }
.wpm-display { color: var(--accent); }
.accuracy-display { color: var(--success); }
.streak-display { color: var(--warning); }

.text-display {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 32px;
  margin-bottom: 24px;
  font-family: var(--font-mono);
  font-size: 1.3rem;
  line-height: 2;
  letter-spacing: 0.5px;
  min-height: 120px;
  position: relative;
  user-select: none;
  outline: none;
}
.text-display .char { transition: color 0.1s; position: relative; }
.text-display .char.correct { color: var(--success); }
.text-display .char.incorrect { color: var(--error); text-decoration: underline; text-decoration-color: var(--error); }
.text-display .char.current { color: var(--text-primary); background: var(--accent-glow); border-radius: 2px; animation: blink 1s infinite; }
.text-display .char.pending { color: var(--text-muted); }

@keyframes blink {
  0%, 100% { background: var(--accent-glow); }
  50% { background: rgba(108, 99, 255, 0.1); }
}

.start-prompt { text-align: center; color: var(--text-muted); font-size: 0.9rem; margin-top: 12px; animation: pulse 2s infinite; }
@keyframes pulse { 0%, 100% { opacity: 1; } 50% { opacity: 0.5; } }

/* --- Keyboard --- */
.keyboard-container { display: flex; flex-direction: column; align-items: center; gap: 4px; padding: 20px; background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius); margin-bottom: 24px; }
.keyboard-row { display: flex; gap: 4px; }
.key {
  width: 48px; height: 44px;
  display: flex; align-items: center; justify-content: center;
  background: var(--bg-input);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--text-secondary);
  transition: all 0.15s ease;
  position: relative;
  cursor: default;
  text-transform: uppercase;
}
.key.active { background: var(--accent); color: #fff; border-color: var(--accent); box-shadow: 0 0 16px var(--accent-glow); transform: scale(1.08); }
.key.pressed { transform: scale(0.95); background: var(--success); border-color: var(--success); color: #fff; }
.key.wrong { background: var(--error); border-color: var(--error); color: #fff; animation: shake 0.3s; }
@keyframes shake { 25% { transform: translateX(-3px); } 50% { transform: translateX(3px); } 75% { transform: translateX(-2px); } 100% { transform: translateX(0); } }
.key.space { width: 280px; }
.key.wide { width: 72px; font-size: 0.65rem; }
.key.wider { width: 96px; font-size: 0.65rem; }
.key.widest { width: 120px; font-size: 0.65rem; }
.key .finger-dot { position: absolute; bottom: 3px; right: 3px; width: 5px; height: 5px; border-radius: 50%; }
.finger-index .finger-dot { background: var(--finger-index); }
.finger-middle .finger-dot { background: var(--finger-middle); }
.finger-ring .finger-dot { background: var(--finger-ring); }
.finger-pinky .finger-dot { background: var(--finger-pinky); }
.finger-thumb .finger-dot { background: var(--finger-thumb); }
.finger-legend { display: flex; gap: 16px; justify-content: center; margin-top: 8px; font-size: 0.7rem; color: var(--text-muted); }
.finger-legend-item { display: flex; align-items: center; gap: 4px; }
.finger-legend-dot { width: 8px; height: 8px; border-radius: 50%; }

/* --- Results --- */
.results-container { text-align: center; padding: 40px 0; }
.results-icon { font-size: 4rem; margin-bottom: 16px; }
.results-title { font-size: 1.75rem; font-weight: 700; margin-bottom: 8px; }
.results-subtitle { color: var(--text-secondary); margin-bottom: 32px; }
.results-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; margin-bottom: 32px; }
.result-card { background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius); padding: 20px; }
.result-label { font-size: 0.75rem; color: var(--text-muted); text-transform: uppercase; letter-spacing: 1px; margin-bottom: 8px; }
.result-value { font-family: var(--font-mono); font-size: 2rem; font-weight: 700; }
.xp-gain {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 12px 24px; border-radius: 24px;
  background: var(--accent-glow); color: var(--accent);
  font-family: var(--font-mono); font-weight: 700; font-size: 1.2rem;
  margin-bottom: 24px; animation: pop 0.5s ease;
}
@keyframes pop { 0% { transform: scale(0.5); opacity: 0; } 70% { transform: scale(1.1); } 100% { transform: scale(1); opacity: 1; } }
.problem-keys { background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius); padding: 20px; margin-bottom: 24px; }
.problem-keys h4 { margin-bottom: 12px; font-size: 0.9rem; }
.problem-key-list { display: flex; gap: 8px; justify-content: center; flex-wrap: wrap; }
.problem-key-chip { padding: 6px 14px; border-radius: 8px; background: var(--error-glow); color: var(--error); font-family: var(--font-mono); font-weight: 600; font-size: 0.85rem; }
.results-actions { display: flex; gap: 12px; justify-content: center; }

/* --- Stats Page --- */
.stats-detail-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; margin-bottom: 32px; }
.stats-section { background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius); padding: 24px; }
.stats-section h3 { margin-bottom: 16px; font-size: 1rem; }
.heatmap { display: grid; grid-template-columns: repeat(10, 1fr); gap: 4px; }
.heatmap-key {
  aspect-ratio: 1;
  display: flex; align-items: center; justify-content: center;
  border-radius: var(--radius-sm);
  font-family: var(--font-mono); font-size: 0.75rem; font-weight: 600;
  border: 1px solid var(--border); transition: var(--transition);
}

/* --- Game --- */
.game-area { position: relative; width: 100%; height: 400px; background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius); overflow: hidden; margin-bottom: 24px; }
.falling-word {
  position: absolute;
  font-family: var(--font-mono); font-size: 1rem; font-weight: 600;
  padding: 4px 12px; border-radius: 6px;
  background: var(--bg-card-hover); border: 1px solid var(--accent); color: var(--accent);
  transition: background 0.15s; white-space: nowrap;
}
.falling-word.target { background: var(--accent-glow); border-color: var(--accent); color: var(--text-primary); }
.falling-word .typed { color: var(--success); }
.game-input-area { display: flex; gap: 12px; align-items: center; }
.game-input {
  flex: 1; padding: 12px 16px;
  border-radius: var(--radius-sm); border: 1px solid var(--border);
  background: var(--bg-input); color: var(--text-primary);
  font-family: var(--font-mono); font-size: 1rem;
  outline: none; transition: var(--transition);
}
.game-input:focus { border-color: var(--accent); box-shadow: 0 0 12px var(--accent-glow); }
.game-stats { display: flex; gap: 24px; margin-bottom: 16px; justify-content: center; }

/* --- Settings Modal --- */
.modal-overlay { position: fixed; inset: 0; background: rgba(0,0,0,0.6); backdrop-filter: blur(4px); display: flex; align-items: center; justify-content: center; z-index: 1000; }
.modal { background: var(--bg-secondary); border: 1px solid var(--border); border-radius: var(--radius-lg); padding: 32px; max-width: 480px; width: 90%; box-shadow: var(--shadow); }
.modal h2 { margin-bottom: 20px; }
.modal-field { margin-bottom: 16px; }
.modal-field label { display: block; font-size: 0.85rem; color: var(--text-secondary); margin-bottom: 6px; }
.modal-field select, .modal-field input[type="text"] { width: 100%; padding: 10px 12px; border-radius: var(--radius-sm); border: 1px solid var(--border); background: var(--bg-input); color: var(--text-primary); font-size: 0.9rem; outline: none; }
.toggle-row { display: flex; justify-content: space-between; align-items: center; padding: 8px 0; }
.toggle { position: relative; width: 44px; height: 24px; background: var(--bg-input); border-radius: 12px; cursor: pointer; border: 1px solid var(--border); transition: var(--transition); }
.toggle.on { background: var(--accent); border-color: var(--accent); }
.toggle::after { content: ''; position: absolute; top: 2px; left: 2px; width: 18px; height: 18px; background: #fff; border-radius: 50%; transition: var(--transition); }
.toggle.on::after { left: 22px; }
.modal-actions { display: flex; gap: 8px; justify-content: flex-end; margin-top: 24px; }

/* --- Toast --- */
.toast {
  position: fixed; bottom: 24px; right: 24px;
  padding: 12px 20px; border-radius: var(--radius-sm);
  background: var(--bg-card); border: 1px solid var(--accent);
  color: var(--text-primary); font-size: 0.85rem;
  box-shadow: var(--shadow); z-index: 2000;
  animation: slideIn 0.3s ease, fadeOut 0.3s ease 2.7s forwards;
}
@keyframes slideIn { from { transform: translateX(100%); opacity: 0; } to { transform: translateX(0); opacity: 1; } }
@keyframes fadeOut { to { opacity: 0; transform: translateY(10px); } }

/* --- Level Up --- */
.level-up-overlay { position: fixed; inset: 0; background: rgba(0,0,0,0.7); display: flex; align-items: center; justify-content: center; z-index: 3000; animation: fadeIn 0.3s; }
.level-up-card { text-align: center; padding: 48px; background: var(--bg-secondary); border: 2px solid var(--accent); border-radius: var(--radius-lg); box-shadow: 0 0 60px var(--accent-glow); animation: pop 0.5s ease; }
.level-up-card h2 { font-size: 2rem; background: linear-gradient(135deg, var(--accent), var(--accent-secondary)); -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text; margin-bottom: 8px; }
.level-up-card .new-level { font-family: var(--font-mono); font-size: 3rem; font-weight: 700; color: var(--accent); margin: 16px 0; }

.fade-in { animation: fadeIn 0.3s ease; }
@keyframes fadeIn { from { opacity: 0; transform: translateY(8px); } to { opacity: 1; transform: translateY(0); } }

/* --- Responsive --- */
@media (max-width: 768px) {
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .quick-actions { grid-template-columns: 1fr; }
  .results-grid { grid-template-columns: repeat(2, 1fr); }
  .stats-detail-grid { grid-template-columns: 1fr; }
  .key { width: 36px; height: 36px; font-size: 0.7rem; }
  .key.space { width: 180px; }
  .key.wide { width: 54px; }
  .key.wider { width: 72px; }
  .key.widest { width: 90px; }
  .text-display { font-size: 1rem; padding: 20px; }
  .nav-links { gap: 0; }
  .nav-link { padding: 6px 10px; font-size: 0.8rem; }
}