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

:root {
  --bg-primary: #0a0e27;
  --bg-secondary: #151b3d;
  --bg-card: #1a2142;
  --accent-primary: #00d4ff;
  --accent-secondary: #00ff88;
  --text-primary: #ffffff;
  --text-secondary: #a0aec0;
  --text-muted: #718096;
  --border-color: rgba(255, 255, 255, 0.1);
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.3);
  --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.5);
  --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  background: linear-gradient(135deg, var(--bg-primary) 0%, #0f1629 100%);
  color: var(--text-primary);
  min-height: 100vh;
  overflow-x: hidden;
  line-height: 1.5;
}

.screen {
  display: none;
  min-height: 100vh;
  padding: 24px;
  opacity: 0;
  transform: translateY(20px);
  transition: var(--transition);
}

.screen.active {
  display: flex;
  opacity: 1;
  transform: translateY(0);
  animation: fadeInUp 0.6s ease-out;
}

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  width: 100%;
}

.header-section {
  text-align: center;
  margin-bottom: 48px;
  animation: fadeInDown 0.8s ease-out;
}

@keyframes fadeInDown {
  from {
    opacity: 0;
    transform: translateY(-20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.main-title {
  font-size: 56px;
  font-weight: 700;
  margin-bottom: 16px;
  background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  letter-spacing: -1px;
}

.subtitle {
  font-size: 20px;
  color: var(--text-secondary);
  font-weight: 400;
}

.personality-section {
  margin-bottom: 48px;
}

.section-title {
  font-size: 24px;
  font-weight: 600;
  text-align: center;
  margin-bottom: 24px;
  color: var(--text-primary);
}

.personality-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 20px;
  max-width: 800px;
  margin: 0 auto 32px;
}

.personality-card {
  position: relative;
  background: var(--bg-card);
  border: 2px solid var(--border-color);
  border-radius: 16px;
  padding: 24px 16px;
  cursor: pointer;
  transition: var(--transition);
  overflow: hidden;
  text-align: center;
  backdrop-filter: blur(10px);
}

.personality-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
  opacity: 0;
  transition: var(--transition);
  border-radius: 16px;
}

.personality-card:hover::before {
  opacity: 0.08;
}

.personality-card:hover {
  transform: translateY(-4px);
  border-color: var(--accent-primary);
  box-shadow: 0 8px 24px rgba(0, 212, 255, 0.15);
}

.personality-card.selected {
  border-color: var(--accent-secondary);
  background: linear-gradient(135deg, rgba(0, 212, 255, 0.05), rgba(0, 255, 136, 0.05));
}

.personality-card.selected::before {
  opacity: 0.1;
}

.personality-accent {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--accent-primary), var(--accent-secondary));
  opacity: 0;
  transition: var(--transition);
}

.personality-card.selected .personality-accent {
  opacity: 1;
}

.personality-icon {
  width: 56px;
  height: 56px;
  margin: 0 auto 16px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(0, 212, 255, 0.1);
  border-radius: 12px;
  transition: var(--transition);
}

.personality-card:hover .personality-icon {
  background: rgba(0, 212, 255, 0.2);
  transform: scale(1.05);
}

.personality-card.selected .personality-icon {
  background: rgba(0, 255, 136, 0.2);
}

.personality-icon svg {
  width: 28px;
  height: 28px;
  color: var(--accent-primary);
}

.personality-card.selected .personality-icon svg {
  color: var(--accent-secondary);
}

.personality-card h3 {
  font-size: 16px;
  font-weight: 600;
  margin-bottom: 4px;
  position: relative;
  z-index: 1;
  color: var(--text-primary);
}

.personality-card p {
  font-size: 13px;
  color: var(--text-secondary);
  position: relative;
  z-index: 1;
}

.exercise-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 32px;
  margin-bottom: 64px;
  max-width: 800px;
  margin-left: auto;
  margin-right: auto;
}

.exercise-card {
  position: relative;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 20px;
  padding: 48px 32px;
  cursor: pointer;
  transition: var(--transition);
  overflow: hidden;
  text-align: center;
  backdrop-filter: blur(10px);
}

.exercise-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
  opacity: 0;
  transition: var(--transition);
  border-radius: 20px;
}

.exercise-card:hover::before {
  opacity: 0.1;
}

.exercise-card:hover {
  transform: translateY(-8px);
  border-color: var(--accent-primary);
  box-shadow: 0 16px 48px rgba(0, 212, 255, 0.2);
}

.exercise-card:active {
  transform: translateY(-4px);
}

.card-accent {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--accent-primary), var(--accent-secondary));
  opacity: 0;
  transition: var(--transition);
}

.exercise-card:hover .card-accent {
  opacity: 1;
}

.exercise-icon {
  width: 80px;
  height: 80px;
  margin: 0 auto 24px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(0, 212, 255, 0.1);
  border-radius: 20px;
  transition: var(--transition);
}

.exercise-card:hover .exercise-icon {
  background: rgba(0, 212, 255, 0.2);
  transform: scale(1.1);
}

.exercise-icon svg {
  width: 40px;
  height: 40px;
  color: var(--accent-primary);
}

.exercise-card h2 {
  font-size: 28px;
  font-weight: 700;
  margin-bottom: 12px;
  position: relative;
  z-index: 1;
}

.exercise-card p {
  font-size: 16px;
  color: var(--text-secondary);
  position: relative;
  z-index: 1;
}

.personal-best-badge {
  position: absolute;
  top: 16px;
  right: 16px;
  display: flex;
  align-items: center;
  gap: 6px;
  background: rgba(0, 255, 136, 0.1);
  border: 1px solid rgba(0, 255, 136, 0.3);
  border-radius: 12px;
  padding: 6px 12px;
  z-index: 2;
}

.trophy-icon {
  width: 18px;
  height: 18px;
  color: var(--accent-secondary);
}

.best-score {
  font-size: 14px;
  font-weight: 700;
  color: var(--accent-secondary);
}

.features {
  display: flex;
  justify-content: center;
  gap: 48px;
  flex-wrap: wrap;
  padding-top: 32px;
  border-top: 1px solid var(--border-color);
}

.feature-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
  text-align: center;
}

.feature-icon {
  font-size: 32px;
  width: 64px;
  height: 64px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--bg-card);
  border-radius: 16px;
  border: 1px solid var(--border-color);
}

.feature-item span {
  font-size: 14px;
  color: var(--text-secondary);
  font-weight: 600;
}

.tracker-container {
  max-width: 1000px;
  margin: 0 auto;
  width: 100%;
}

.tracker-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 32px;
  gap: 16px;
}

.back-button {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 12px 24px;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  color: var(--text-primary);
  font-size: 16px;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
  font-family: inherit;
}

.back-button:hover {
  background: var(--bg-secondary);
  border-color: var(--accent-primary);
  transform: translateX(-4px);
}

.back-button svg {
  width: 20px;
  height: 20px;
}

.exercise-title {
  font-size: 32px;
  font-weight: 700;
  flex: 1;
  text-align: center;
}

.spacer {
  width: 120px;
}

.video-container {
  position: relative;
  border-radius: 20px;
  overflow: hidden;
  background: var(--bg-card);
  box-shadow: var(--shadow-lg);
  margin-bottom: 32px;
  border: 1px solid var(--border-color);
}

video, canvas {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
}

canvas {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
}

.video-overlay {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  pointer-events: none;
  display: flex;
  padding: 24px;
}

.rep-counter {
  background: rgba(10, 14, 39, 0.85);
  backdrop-filter: blur(16px);
  border-radius: 16px;
  padding: 20px 32px;
  border: 1px solid var(--border-color);
  text-align: center;
  box-shadow: var(--shadow-md);
}

.rep-number {
  font-size: 64px;
  font-weight: 700;
  line-height: 1;
  background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.rep-label {
  font-size: 14px;
  font-weight: 600;
  color: var(--text-secondary);
  margin-top: 4px;
  letter-spacing: 2px;
}

.best-comparison {
  font-size: 12px;
  font-weight: 600;
  color: var(--accent-secondary);
  margin-top: 8px;
  min-height: 18px;
}

.new-record-overlay {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  z-index: 10;
  opacity: 0;
  transition: opacity 0.3s ease;
}

.new-record-overlay.hidden {
  display: none;
}

.new-record-overlay.show {
  display: block;
  opacity: 1;
  animation: recordPulse 0.6s ease-out;
}

@keyframes recordPulse {
  0% {
    transform: translate(-50%, -50%) scale(0.5);
    opacity: 0;
  }
  50% {
    transform: translate(-50%, -50%) scale(1.1);
    opacity: 1;
  }
  100% {
    transform: translate(-50%, -50%) scale(1);
    opacity: 1;
  }
}

.record-content {
  background: rgba(10, 14, 39, 0.95);
  backdrop-filter: blur(20px);
  border-radius: 20px;
  padding: 32px 48px;
  border: 2px solid var(--accent-secondary);
  box-shadow: 0 0 40px rgba(0, 255, 136, 0.4);
  text-align: center;
}

.record-icon {
  font-size: 64px;
  margin-bottom: 16px;
  animation: bounce 0.6s ease;
}

@keyframes bounce {
  0%, 100% {
    transform: translateY(0);
  }
  50% {
    transform: translateY(-10px);
  }
}

.record-text {
  font-size: 32px;
  font-weight: 700;
  color: var(--accent-secondary);
  letter-spacing: 2px;
}

.feedback-panel {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 20px;
  padding: 32px;
  box-shadow: var(--shadow-md);
}

.status-indicator {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 20px;
  padding-bottom: 20px;
  border-bottom: 1px solid var(--border-color);
}

.status-dot {
  width: 12px;
  height: 12px;
  background: var(--accent-secondary);
  border-radius: 50%;
  animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {
  0%, 100% {
    opacity: 1;
    transform: scale(1);
  }
  50% {
    opacity: 0.5;
    transform: scale(1.2);
  }
}

#status-text {
  font-size: 14px;
  font-weight: 600;
  color: var(--accent-secondary);
  text-transform: uppercase;
  letter-spacing: 1px;
}

.feedback-text {
  font-size: 20px;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 24px;
  min-height: 30px;
}

.metrics {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 24px;
}

.metric-item {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 20px;
  background: var(--bg-secondary);
  border-radius: 12px;
  border: 1px solid var(--border-color);
}

.metric-label {
  font-size: 13px;
  color: var(--text-muted);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 1px;
}

.metric-value {
  font-size: 28px;
  font-weight: 700;
  color: var(--accent-primary);
}

@media (max-width: 768px) {
  .main-title {
    font-size: 40px;
  }

  .subtitle {
    font-size: 16px;
  }

  .exercise-grid {
    grid-template-columns: 1fr;
    gap: 20px;
  }

  .features {
    gap: 24px;
  }

  .tracker-header {
    flex-direction: column;
    align-items: flex-start;
  }

  .exercise-title {
    text-align: left;
  }

  .spacer {
    display: none;
  }

  .rep-number {
    font-size: 48px;
  }

  .feedback-panel {
    padding: 24px;
  }

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

@media (max-width: 480px) {
  .screen {
    padding: 16px;
  }

  .header-section {
    margin-bottom: 40px;
  }

  .main-title {
    font-size: 32px;
  }

  .exercise-card {
    padding: 32px 24px;
  }

  .exercise-card h2 {
    font-size: 24px;
  }
}