/* ============================================
   TypeBlitz — Premium Typing Speed Game
   Design System & Styles
   ============================================ */

/* --- CSS Custom Properties --- */
:root {
  /* Colors */
  --bg-primary: #0a0a0f;
  --bg-secondary: #12121a;
  --bg-card: rgba(20, 20, 32, 0.7);
  --bg-card-hover: rgba(30, 30, 48, 0.8);
  --bg-glass: rgba(255, 255, 255, 0.03);
  --bg-input: rgba(15, 15, 25, 0.9);

  --text-primary: #e8e8f0;
  --text-secondary: #8888a0;
  --text-muted: #55556a;
  --text-correct: #4ade80;
  --text-error: #f87171;
  --text-current: #ffffff;

  --accent-primary: #7c3aed;
  --accent-secondary: #a855f7;
  --accent-glow: rgba(124, 58, 237, 0.3);
  --accent-gradient: linear-gradient(135deg, #7c3aed, #a855f7, #c084fc);

  --border-subtle: rgba(255, 255, 255, 0.06);
  --border-active: rgba(124, 58, 237, 0.4);

  /* Speed Level Colors */
  --level-beginner: #64748b;
  --level-average: #3b82f6;
  --level-fast: #8b5cf6;
  --level-pro: #f59e0b;
  --level-demon: #ef4444;
  --level-legend: #ec4899;

  /* Typography */
  --font-primary: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', monospace;

  /* Spacing */
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 24px;

  /* Shadows */
  --shadow-card: 0 4px 24px rgba(0, 0, 0, 0.3), 0 1px 2px rgba(0, 0, 0, 0.2);
  --shadow-glow: 0 0 40px rgba(124, 58, 237, 0.15);
  --shadow-input: inset 0 2px 6px rgba(0, 0, 0, 0.3);

  /* Transitions */
  --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-normal: 250ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 400ms cubic-bezier(0.4, 0, 0.2, 1);
}

/* --- Reset & Base --- */
*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-primary);
  background: var(--bg-primary);
  color: var(--text-primary);
  min-height: 100vh;
  overflow-x: hidden;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* --- Background Particles --- */
.bg-particles {
  position: fixed;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  overflow: hidden;
}

.bg-particles .particle {
  position: absolute;
  border-radius: 50%;
  opacity: 0;
  animation: particleFloat linear infinite;
}

@keyframes particleFloat {
  0% {
    opacity: 0;
    transform: translateY(100vh) scale(0);
  }
  10% {
    opacity: 1;
  }
  90% {
    opacity: 1;
  }
  100% {
    opacity: 0;
    transform: translateY(-10vh) scale(1);
  }
}

/* --- App Container --- */
.app-container {
  position: relative;
  z-index: 1;
  max-width: 900px;
  margin: 0 auto;
  padding: 24px 20px 40px;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* --- Header --- */
.app-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 0;
  margin-bottom: 24px;
  animation: fadeInDown 0.6s ease;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
}

.logo-icon {
  font-size: 28px;
  animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {
  0%, 100% { transform: scale(1); }
  50% { transform: scale(1.15); }
}

.logo h1 {
  font-size: 1.8rem;
  font-weight: 800;
  letter-spacing: -0.5px;
  background: linear-gradient(135deg, #e8e8f0, #a0a0b8);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.logo h1 .accent {
  background: var(--accent-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.header-stats {
  display: flex;
  gap: 20px;
}

.header-stat {
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: 2px;
}

.header-stat-label {
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 1px;
  color: var(--text-muted);
  font-weight: 600;
}

.header-stat-value {
  font-size: 1.2rem;
  font-weight: 700;
  font-family: var(--font-mono);
  color: var(--accent-secondary);
}

/* --- Main Content --- */
.main-content {
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 20px;
}

/* --- Level Badge --- */
.level-badge-container {
  display: flex;
  justify-content: center;
  animation: fadeInDown 0.5s ease 0.1s both;
}

.level-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 20px;
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: 50px;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-secondary);
  transition: all var(--transition-normal);
  backdrop-filter: blur(12px);
}

.level-badge.active {
  border-color: var(--border-active);
  box-shadow: var(--shadow-glow);
}

.level-icon {
  font-size: 1.1rem;
}

/* --- Stats Bar --- */
.stats-bar {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 12px;
  animation: fadeInDown 0.5s ease 0.2s both;
}

.stat-card {
  position: relative;
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 14px 16px;
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  backdrop-filter: blur(12px);
  transition: all var(--transition-normal);
  overflow: hidden;
}

.stat-card::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(124, 58, 237, 0.05), transparent);
  opacity: 0;
  transition: opacity var(--transition-normal);
}

.stat-card:hover::before {
  opacity: 1;
}

.stat-card:hover {
  border-color: var(--border-active);
  transform: translateY(-1px);
}

.stat-icon {
  font-size: 1.3rem;
  flex-shrink: 0;
}

.stat-info {
  display: flex;
  flex-direction: column;
  gap: 1px;
  z-index: 1;
}

.stat-label {
  font-size: 0.65rem;
  text-transform: uppercase;
  letter-spacing: 1px;
  color: var(--text-muted);
  font-weight: 600;
}

.stat-value {
  font-size: 1.1rem;
  font-weight: 700;
  font-family: var(--font-mono);
  color: var(--text-primary);
  transition: color var(--transition-fast);
}

/* Timer Ring */
.stat-ring {
  position: absolute;
  right: 10px;
  top: 50%;
  transform: translateY(-50%);
  width: 32px;
  height: 32px;
  opacity: 0.5;
}

.stat-ring svg {
  width: 100%;
  height: 100%;
  transform: rotate(-90deg);
}

.ring-bg {
  fill: none;
  stroke: var(--border-subtle);
  stroke-width: 2.5;
}

.ring-fill {
  fill: none;
  stroke: var(--accent-primary);
  stroke-width: 2.5;
  stroke-linecap: round;
  transition: stroke-dasharray 1s linear;
}

/* --- Difficulty Selector --- */
.difficulty-selector {
  display: flex;
  position: relative;
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 4px;
  gap: 4px;
  animation: fadeInDown 0.5s ease 0.3s both;
}

.diff-btn {
  flex: 1;
  padding: 10px 16px;
  background: transparent;
  border: none;
  border-radius: var(--radius-md);
  font-family: var(--font-primary);
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--text-secondary);
  cursor: pointer;
  transition: all var(--transition-normal);
  z-index: 1;
  position: relative;
}

.diff-btn:hover {
  color: var(--text-primary);
}

.diff-btn.active {
  color: #ffffff;
}

.diff-slider {
  position: absolute;
  top: 4px;
  left: 4px;
  width: calc(25% - 5px);
  height: calc(100% - 8px);
  background: var(--accent-gradient);
  border-radius: var(--radius-md);
  transition: transform var(--transition-normal);
  box-shadow: 0 2px 10px rgba(124, 58, 237, 0.3);
}

/* --- Typing Zone --- */
.typing-zone {
  display: flex;
  flex-direction: column;
  gap: 16px;
  animation: fadeInUp 0.6s ease 0.4s both;
}

.text-display {
  position: relative;
  padding: 28px 28px 24px;
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  font-family: var(--font-mono);
  font-size: 1.2rem;
  line-height: 2;
  letter-spacing: 0.3px;
  color: var(--text-muted);
  min-height: 140px;
  backdrop-filter: blur(12px);
  transition: border-color var(--transition-normal), box-shadow var(--transition-normal);
  word-wrap: break-word;
  overflow-wrap: break-word;
}

.text-display.active {
  border-color: var(--border-active);
  box-shadow: var(--shadow-glow);
}

.text-display .char {
  position: relative;
  transition: color var(--transition-fast);
}

.text-display .char.correct {
  color: var(--text-correct);
}

.text-display .char.incorrect {
  color: var(--text-error);
  text-decoration: underline;
  text-decoration-style: wavy;
  text-underline-offset: 4px;
}

.text-display .char.current {
  color: var(--text-current);
}

.text-display .char.current::before {
  content: '';
  position: absolute;
  left: -1px;
  top: 2px;
  width: 2px;
  height: 1.2em;
  background: var(--accent-secondary);
  border-radius: 2px;
  animation: blink 1s step-end infinite;
}

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

/* Input Wrapper */
.input-wrapper {
  position: relative;
}

.type-input {
  width: 100%;
  padding: 16px 20px;
  background: var(--bg-input);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  font-family: var(--font-mono);
  font-size: 1rem;
  color: var(--text-primary);
  outline: none;
  resize: none;
  height: 56px;
  transition: all var(--transition-normal);
  box-shadow: var(--shadow-input);
}

.type-input::placeholder {
  color: var(--text-muted);
  font-family: var(--font-primary);
}

.type-input:focus {
  border-color: var(--accent-primary);
  box-shadow: var(--shadow-input), 0 0 0 3px var(--accent-glow);
}

/* Typing Hint */
.typing-hint {
  text-align: center;
  font-size: 0.75rem;
  color: var(--text-muted);
  letter-spacing: 0.3px;
}

.hint-key {
  display: inline-block;
  padding: 2px 8px;
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: 4px;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 600;
  color: var(--text-secondary);
}

/* --- Results Panel --- */
.results-panel {
  background: var(--bg-card);
  border: 1px solid var(--border-active);
  border-radius: var(--radius-xl);
  padding: 36px;
  backdrop-filter: blur(16px);
  box-shadow: var(--shadow-glow);
  animation: scaleIn 0.5s cubic-bezier(0.34, 1.56, 0.64, 1);
}

.results-panel.hidden {
  display: none;
}

@keyframes scaleIn {
  from {
    opacity: 0;
    transform: scale(0.92);
  }
  to {
    opacity: 1;
    transform: scale(1);
  }
}

.results-header {
  text-align: center;
  margin-bottom: 28px;
}

.results-header h2 {
  font-size: 1.6rem;
  font-weight: 800;
  margin-bottom: 12px;
  background: var(--accent-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.results-level {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 24px;
  background: rgba(124, 58, 237, 0.1);
  border: 1px solid var(--border-active);
  border-radius: 50px;
  font-weight: 700;
  font-size: 1rem;
  color: var(--accent-secondary);
  animation: bounceIn 0.6s ease 0.3s both;
}

@keyframes bounceIn {
  0% { transform: scale(0); }
  50% { transform: scale(1.1); }
  100% { transform: scale(1); }
}

.results-level-icon {
  font-size: 1.3rem;
}

/* Results Grid */
.results-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
  margin-bottom: 28px;
}

.result-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
  padding: 18px 12px;
  background: var(--bg-glass);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  transition: all var(--transition-normal);
}

.result-item:hover {
  border-color: var(--border-active);
  transform: translateY(-2px);
}

.result-number {
  font-size: 1.6rem;
  font-weight: 800;
  font-family: var(--font-mono);
  background: var(--accent-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.result-wpm .result-number {
  font-size: 2rem;
}

.result-label {
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 1px;
  color: var(--text-muted);
  font-weight: 600;
}

/* Results Chart */
.results-chart {
  margin-bottom: 24px;
  padding: 20px;
  background: var(--bg-glass);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
}

.results-chart h3 {
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 1px;
  color: var(--text-muted);
  margin-bottom: 12px;
  font-weight: 600;
}

.results-chart canvas {
  width: 100% !important;
  height: 180px !important;
}

/* Results Actions */
.results-actions {
  display: flex;
  gap: 12px;
  justify-content: center;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 28px;
  border: none;
  border-radius: var(--radius-md);
  font-family: var(--font-primary);
  font-size: 0.9rem;
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition-normal);
}

.btn-primary {
  background: var(--accent-gradient);
  color: #ffffff;
  box-shadow: 0 4px 16px rgba(124, 58, 237, 0.3);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 24px rgba(124, 58, 237, 0.4);
}

.btn-secondary {
  background: var(--bg-glass);
  color: var(--text-primary);
  border: 1px solid var(--border-subtle);
}

.btn-secondary:hover {
  border-color: var(--border-active);
  transform: translateY(-2px);
}

/* --- Speed Legend --- */
.speed-legend {
  margin-top: 32px;
  padding: 20px 24px;
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  backdrop-filter: blur(12px);
  animation: fadeInUp 0.5s ease 0.5s both;
}

.speed-legend h3 {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 1.5px;
  color: var(--text-muted);
  margin-bottom: 12px;
  font-weight: 700;
}

.legend-items {
  display: flex;
  flex-wrap: wrap;
  gap: 12px 24px;
}

.legend-item {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.78rem;
  color: var(--text-secondary);
  font-weight: 500;
}

.legend-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--dot-color);
  box-shadow: 0 0 8px var(--dot-color);
}

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

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(16px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* Correct character flash */
.char-flash {
  animation: charFlash 0.3s ease;
}

@keyframes charFlash {
  0% { text-shadow: 0 0 8px var(--text-correct); }
  100% { text-shadow: none; }
}

/* Error shake */
.shake {
  animation: shake 0.3s ease;
}

@keyframes shake {
  0%, 100% { transform: translateX(0); }
  25% { transform: translateX(-4px); }
  75% { transform: translateX(4px); }
}

/* Score pop */
.score-pop {
  animation: scorePop 0.4s cubic-bezier(0.34, 1.56, 0.64, 1);
}

@keyframes scorePop {
  0% { transform: scale(1); }
  50% { transform: scale(1.2); }
  100% { transform: scale(1); }
}

/* WPM highlight */
.wpm-highlight {
  color: var(--accent-secondary) !important;
}

/* --- Responsive --- */
@media (max-width: 768px) {
  .app-container {
    padding: 16px 12px 32px;
  }

  .stats-bar {
    grid-template-columns: repeat(2, 1fr);
  }

  .results-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .text-display {
    font-size: 1rem;
    padding: 20px;
  }

  .logo h1 {
    font-size: 1.4rem;
  }

  .header-stats {
    gap: 12px;
  }

  .results-panel {
    padding: 24px 16px;
  }

  .legend-items {
    gap: 8px 16px;
  }
}

@media (max-width: 480px) {
  .stats-bar {
    grid-template-columns: 1fr 1fr;
    gap: 8px;
  }

  .stat-card {
    padding: 10px 12px;
  }

  .difficulty-selector {
    flex-wrap: wrap;
  }

  .diff-btn {
    font-size: 0.75rem;
    padding: 8px 12px;
  }

  .results-grid {
    grid-template-columns: 1fr 1fr;
  }

  .results-actions {
    flex-direction: column;
  }

  .btn {
    width: 100%;
    justify-content: center;
  }
}