:root {
  --bg-color: #f8fafc;
  --text-color: #0f172a;
  --text-muted: #64748b;
  --primary-color: #3b82f6;
  --primary-hover: #2563eb;
  --secondary-color: #10b981;
  --danger-color: #ef4444;
  --panel-bg: rgba(255, 255, 255, 0.95);
  --modal-bg: #ffffff;
  --shadow-sm: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
  --shadow-md: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
  --border-color: #e2e8f0;
}

[data-theme="dark"] {
  --bg-color: #0f172a;
  --text-color: #f8fafc;
  --text-muted: #94a3b8;
  --primary-color: #60a5fa;
  --primary-hover: #93c5fd;
  --secondary-color: #34d399;
  --danger-color: #f87171;
  --panel-bg: rgba(30, 41, 59, 0.95);
  --modal-bg: #1e293b;
  --shadow-sm: 0 4px 6px -1px rgba(0, 0, 0, 0.5);
  --shadow-md: 0 10px 15px -3px rgba(0, 0, 0, 0.5);
  --shadow-lg: 0 20px 25px -5px rgba(0, 0, 0, 0.5);
  --border-color: #334155;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  user-select: none;
}

body {
  font-family: 'Inter', sans-serif;
  background-color: var(--bg-color);
  color: var(--text-color);
  overflow: hidden;
  transition: background-color 0.3s ease, color 0.3s ease;
  touch-action: none;
}

h1, h2, h3, .logo {
  font-family: 'Outfit', sans-serif;
}

#game-wrapper {
  display: flex;
  flex-direction: column;
  height: 100vh;
  width: 100vw;
}

.game-header {
  height: 60px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 0 24px;
  background: var(--panel-bg);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border-color);
  z-index: 10;
}

.logo {
  display: flex;
  align-items: center;
  gap: 12px;
  font-weight: 800;
  font-size: 1.25rem;
  letter-spacing: 1px;
  color: var(--primary-color);
}

.game-footer {
  height: 50px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 0 24px;
  background: var(--panel-bg);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-top: 1px solid var(--border-color);
  font-size: 0.8rem;
  color: var(--text-muted);
  z-index: 10;
}

@media (max-width: 600px) {
  .game-footer {
    flex-direction: column;
    justify-content: center;
    gap: 4px;
    height: 60px;
  }
}

#game-container {
  flex: 1;
  position: relative;
  width: 100%;
  overflow: hidden;
}

canvas {
  display: block;
  width: 100%;
  height: 100%;
}

.ui-layer {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  display: flex;
  flex-direction: column;
}

.top-bar {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  padding: 20px 24px;
  pointer-events: auto;
}

.score-container {
  background: var(--panel-bg);
  padding: 12px 20px;
  border-radius: 12px;
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--border-color);
  backdrop-filter: blur(8px);
}

.score-text {
  font-size: 1.5rem;
  font-weight: 800;
  font-family: 'Outfit', sans-serif;
  color: var(--primary-color);
  transition: transform 0.2s cubic-bezier(0.175, 0.885, 0.32, 1.275);
  display: inline-block;
}

.best-score {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-top: 4px;
  font-weight: 500;
}

.btn-icon {
  background: var(--panel-bg);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  width: 44px;
  height: 44px;
  cursor: pointer;
  display: flex;
  justify-content: center;
  align-items: center;
  box-shadow: var(--shadow-sm);
  color: var(--text-color);
  transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
}

.btn-icon:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
  color: var(--primary-color);
  border-color: var(--primary-color);
}

.btn-icon svg {
  width: 20px;
  height: 20px;
  fill: currentColor;
}

/* Modals */
.modal {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(0,0,0,0.4);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  display: flex;
  justify-content: center;
  align-items: center;
  z-index: 9999;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.3s ease, visibility 0.3s ease;
  visibility: hidden;
}

.modal.active {
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
}

.modal-content {
  background: var(--modal-bg);
  padding: 40px;
  border-radius: 24px;
  box-shadow: var(--shadow-lg);
  border: 1px solid var(--border-color);
  text-align: center;
  max-width: 500px;
  width: 90%;
  max-height: 85vh;
  display: flex;
  flex-direction: column;
  transform: translateY(20px) scale(0.95);
  transition: transform 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

.modal-scroll-area {
  overflow-y: auto;
  flex: 1;
  margin: 10px 0 20px 0;
  padding-right: 5px;
}

/* Custom scrollbar for modal content */
.modal-scroll-area::-webkit-scrollbar {
  width: 6px;
}
.modal-scroll-area::-webkit-scrollbar-track {
  background: transparent; 
}
.modal-scroll-area::-webkit-scrollbar-thumb {
  background: var(--border-color); 
  border-radius: 10px;
}
.modal-scroll-area::-webkit-scrollbar-thumb:hover {
  background: var(--text-muted); 
}

.modal.active .modal-content {
  transform: translateY(0) scale(1);
}

.game-icon {
  width: 64px;
  height: 64px;
  color: var(--primary-color);
  margin-bottom: 16px;
}

.gradient-text {
  font-size: 3rem;
  font-weight: 800;
  margin-bottom: 8px;
  background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.subtitle {
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--text-color);
  margin-bottom: 16px;
}

.desc {
  font-size: 0.95rem;
  color: var(--text-muted);
  margin-bottom: 30px;
  line-height: 1.5;
}

.how-to-play {
  background: var(--bg-color);
  border: 1px solid var(--border-color);
  border-radius: 16px;
  padding: 20px;
  margin-bottom: 30px;
  text-align: left;
}

.how-to-play h3 {
  margin-bottom: 12px;
  font-size: 1rem;
  color: var(--text-color);
  text-align: center;
}

.instructions {
  display: flex;
  gap: 20px;
  justify-content: space-between;
}

.inst-col {
  flex: 1;
}

.inst-col strong {
  display: block;
  margin-bottom: 10px;
  font-size: 0.85rem;
  color: var(--primary-color);
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.inst-col ul {
  list-style: none;
  font-size: 0.9rem;
  color: var(--text-muted);
}

.inst-col li {
  margin-bottom: 8px;
  display: flex;
  align-items: center;
  gap: 8px;
}

kbd {
  background: var(--modal-bg);
  border: 1px solid var(--border-color);
  border-radius: 4px;
  padding: 2px 6px;
  font-size: 0.75rem;
  font-family: monospace;
  box-shadow: 0 2px 0 var(--border-color);
  color: var(--text-color);
  font-weight: bold;
}

.btn-primary, .btn-secondary {
  border: none;
  padding: 16px 32px;
  font-size: 1.1rem;
  font-weight: 700;
  font-family: 'Outfit', sans-serif;
  border-radius: 16px;
  cursor: pointer;
  transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
  width: 100%;
  display: block;
  margin-bottom: 12px;
}

.btn-primary {
  background: var(--primary-color);
  color: #fff;
  box-shadow: 0 4px 15px rgba(59, 130, 246, 0.3);
}

.btn-primary:hover {
  background: var(--primary-hover);
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(59, 130, 246, 0.4);
}

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

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

.text-danger {
  color: var(--danger-color);
}

.final-score-box {
  background: var(--bg-color);
  border: 1px solid var(--border-color);
  border-radius: 16px;
  padding: 30px;
  margin: 24px 0;
}

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

.score-value {
  font-size: 4rem;
  font-family: 'Outfit', sans-serif;
  font-weight: 800;
  color: var(--primary-color);
  line-height: 1;
  margin: 10px 0;
}

.high-score-notify {
  display: inline-block;
  background: var(--secondary-color);
  color: #fff;
  padding: 4px 12px;
  border-radius: 20px;
  font-size: 0.8rem;
  font-weight: bold;
  animation: pulse 1.5s infinite;
}

@keyframes pulse {
  0% { transform: scale(1); }
  50% { transform: scale(1.05); }
  100% { transform: scale(1); }
}

.settings-group {
  margin-bottom: 20px;
  text-align: left;
}

.settings-group label {
  display: block;
  margin-bottom: 10px;
  font-weight: 600;
  color: var(--text-muted);
  font-size: 0.9rem;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.btn-group {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.toggle-btn {
  flex: 1;
  background: var(--bg-color);
  border: 1px solid var(--border-color);
  color: var(--text-color);
  padding: 10px 16px;
  border-radius: 12px;
  cursor: pointer;
  font-weight: 500;
  transition: all 0.2s;
  min-width: max-content;
}

.toggle-btn:hover {
  background: var(--border-color);
}

.toggle-btn.active {
  background: var(--primary-color);
  border-color: var(--primary-color);
  color: #fff;
}

.btn-danger-outline {
  width: 100%;
  background: transparent;
  border: 1px solid var(--danger-color);
  color: var(--danger-color);
  padding: 12px;
  border-radius: 12px;
  cursor: pointer;
  font-weight: 600;
  transition: all 0.2s;
}

.btn-danger-outline:hover {
  background: var(--danger-color);
  color: #fff;
}

@media (max-width: 600px) {
  .instructions {
    flex-direction: column;
    gap: 15px;
  }
  .gradient-text { font-size: 2.2rem; }
  .modal-content { padding: 24px; }
  .score-value { font-size: 3rem; }
}