:root {
      --primary: #f97316;
      --primary-glow: rgba(249, 115, 22, 0.4);
      --accent: #eab308;
      --bg-sky: #38bdf8;
      --glass: rgba(255, 255, 255, 0.9);
      --glass-dark: rgba(15, 23, 42, 0.85);
      --glass-border: rgba(255, 255, 255, 0.4);
      --text: #0f172a;
    }

    * {
      box-sizing: border-box;
      user-select: none;
      -webkit-user-select: none;
      touch-action: manipulation;
    }

    body, html {
      margin: 0;
      padding: 0;
      width: 100%;
      height: 100%;
      overflow: hidden;
      background: linear-gradient(180deg, #a5b4fc 0%, #93c5fd 40%, #f8fafc 100%);
      font-family: 'Outfit', sans-serif;
      color: var(--text);
    }

    #webgl-container {
      position: absolute;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      z-index: 1;
    }

    /* UI Overlay Layer */
    .ui-layer {
      position: absolute;
      inset: 0;
      z-index: 10;
      pointer-events: none;
      display: flex;
      flex-direction: column;
      justify-content: space-between;
      padding: 20px;
    }

    .interactive {
      pointer-events: auto;
    }

    /* Top HUD */
    .hud-top {
      display: flex;
      justify-content: space-between;
      align-items: flex-start;
      width: 100%;
      max-width: 1000px;
      margin: 0 auto;
    }

    .hud-card {
      background: var(--glass);
      backdrop-filter: blur(14px);
      -webkit-backdrop-filter: blur(14px);
      border: 2px solid var(--glass-border);
      border-radius: 20px;
      padding: 10px 22px;
      display: flex;
      align-items: center;
      gap: 12px;
      box-shadow: 0 10px 30px rgba(0, 0, 0, 0.15);
    }

    .hud-stat {
      display: flex;
      flex-direction: column;
    }

    .hud-label {
      font-size: 11px;
      text-transform: uppercase;
      letter-spacing: 1px;
      color: #64748b;
      font-weight: 700;
    }

    .hud-value {
      font-size: 26px;
      font-weight: 900;
      color: #0f172a;
    }

    .hud-value.gold {
      color: #d97706;
      text-shadow: 0 0 10px rgba(217, 119, 6, 0.3);
    }

    .audio-btn {
      background: var(--glass);
      border: 2px solid var(--glass-border);
      border-radius: 50%;
      width: 48px;
      height: 48px;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 22px;
      cursor: pointer;
      color: #0f172a;
      box-shadow: 0 8px 20px rgba(0, 0, 0, 0.15);
    }

    /* Toast Popup */
    #boost-toast {
      position: absolute;
      top: 140px;
      left: 50%;
      transform: translateX(-50%) scale(0.8);
      background: linear-gradient(135deg, #f97316 0%, #eab308 100%);
      color: #fff;
      font-size: 22px;
      font-weight: 900;
      padding: 12px 28px;
      border-radius: 99px;
      box-shadow: 0 12px 35px rgba(249, 115, 22, 0.5);
      z-index: 50;
      opacity: 0;
      pointer-events: none;
      transition: all 0.3s cubic-bezier(0.175, 0.885, 0.32, 1.275);
      text-transform: uppercase;
      letter-spacing: 1px;
      border: 3px solid #fff;
    }

    #boost-toast.show {
      opacity: 1;
      transform: translateX(-50%) scale(1);
    }

    /* Active Powerups Bar */
    .powerup-bars {
      position: absolute;
      top: 90px;
      left: 50%;
      transform: translateX(-50%);
      display: flex;
      flex-direction: column;
      gap: 8px;
      width: 260px;
    }

    .powerup-timer {
      background: var(--glass-dark);
      border: 1px solid rgba(255, 255, 255, 0.2);
      border-radius: 20px;
      padding: 6px 14px;
      display: flex;
      align-items: center;
      gap: 10px;
      overflow: hidden;
      position: relative;
      color: #fff;
      animation: popIn 0.3s cubic-bezier(0.175, 0.885, 0.32, 1.275);
    }

    @keyframes popIn {
      from { transform: scale(0.8); opacity: 0; }
      to { transform: scale(1); opacity: 1; }
    }

    .powerup-timer .fill-bar {
      position: absolute;
      left: 0;
      top: 0;
      bottom: 0;
      width: 100%;
      background: linear-gradient(90deg, #f97316, #eab308);
      z-index: 1;
      transition: width 0.1s linear;
      border-radius: 20px;
    }

    .powerup-timer-content {
      position: relative;
      z-index: 2;
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
      font-size: 13px;
      font-weight: 800;
      text-shadow: 0 1px 3px rgba(0,0,0,0.8);
    }

    /* Modal Screens */
    .modal-backdrop {
      position: absolute;
      inset: 0;
      background: rgba(15, 23, 42, 0.6);
      backdrop-filter: blur(14px);
      -webkit-backdrop-filter: blur(14px);
      z-index: 100;
      display: flex;
      align-items: center;
      justify-content: center;
      padding: 20px;
      transition: opacity 0.3s ease;
    }

    .modal-card {
      background: rgba(255, 255, 255, 0.96);
      border: 3px solid #fff;
      border-radius: 32px;
      width: 100%;
      max-width: 530px;
      padding: 36px;
      box-shadow: 0 25px 60px rgba(0, 0, 0, 0.35);
      text-align: center;
      position: relative;
      overflow: hidden;
      color: #0f172a;
    }

    h1.game-title {
      font-size: 40px;
      font-weight: 900;
      margin: 0 0 6px 0;
      background: linear-gradient(135deg, #f97316 0%, #eab308 50%, #ef4444 100%);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      text-transform: uppercase;
      letter-spacing: 1px;
    }

    .game-subtitle {
      color: #64748b;
      font-size: 15px;
      margin-bottom: 24px;
      font-weight: 700;
    }

    /* Buttons */
    .btn-group {
      display: flex;
      flex-direction: column;
      gap: 12px;
      margin-top: 24px;
    }

    .btn {
      background: linear-gradient(135deg, #f97316 0%, #ef4444 100%);
      color: #fff;
      border: none;
      border-radius: 18px;
      padding: 18px 28px;
      font-size: 20px;
      font-weight: 900;
      cursor: pointer;
      box-shadow: 0 10px 25px rgba(249, 115, 22, 0.4);
      transition: all 0.2s cubic-bezier(0.175, 0.885, 0.32, 1.275);
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 10px;
      text-transform: uppercase;
      letter-spacing: 0.5px;
    }

    .btn:hover {
      transform: translateY(-3px) scale(1.02);
      box-shadow: 0 15px 30px rgba(249, 115, 22, 0.6);
    }

    .btn-secondary {
      background: #f1f5f9;
      border: 2px solid #cbd5e1;
      box-shadow: none;
      color: #334155;
    }

    .btn-secondary:hover {
      background: #e2e8f0;
      color: #0f172a;
      box-shadow: 0 8px 20px rgba(0, 0, 0, 0.1);
    }

    /* Controls Grid */
    .controls-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 10px;
      margin: 20px 0;
      background: #f8fafc;
      padding: 14px;
      border-radius: 20px;
      border: 2px solid #e2e8f0;
    }

    .control-item {
      display: flex;
      flex-direction: column;
      align-items: center;
      gap: 6px;
    }

    .key-badge {
      background: #0f172a;
      border-radius: 8px;
      padding: 4px 10px;
      font-family: monospace;
      font-size: 14px;
      font-weight: bold;
      color: #fbbf24;
      box-shadow: 0 3px 0 rgba(0,0,0,0.2);
    }

    .control-desc {
      font-size: 11px;
      color: #64748b;
      font-weight: 700;
    }

    /* Shop Grid */
    .shop-tabs {
      display: flex;
      gap: 10px;
      margin-bottom: 16px;
      border-bottom: 2px solid #e2e8f0;
      padding-bottom: 10px;
    }

    .shop-tab {
      flex: 1;
      padding: 10px;
      border-radius: 12px;
      background: transparent;
      border: none;
      color: #64748b;
      font-weight: 800;
      cursor: pointer;
      transition: all 0.2s;
    }

    .shop-tab.active {
      background: #f97316;
      color: #fff;
    }

    .shop-items {
      display: flex;
      flex-direction: column;
      gap: 12px;
      max-height: 280px;
      overflow-y: auto;
      padding-right: 6px;
    }

    .shop-item {
      background: #f8fafc;
      border: 2px solid #e2e8f0;
      border-radius: 18px;
      padding: 12px 16px;
      display: flex;
      align-items: center;
      justify-content: space-between;
    }

    .shop-item-info {
      display: flex;
      align-items: center;
      gap: 12px;
      text-align: left;
    }

    .shop-item-icon {
      font-size: 28px;
    }

    .shop-item-title {
      font-weight: 800;
      font-size: 15px;
    }

    .shop-item-desc {
      font-size: 12px;
      color: #64748b;
    }

    .shop-buy-btn {
      background: #d97706;
      color: #fff;
      border: none;
      padding: 8px 16px;
      border-radius: 12px;
      font-weight: 900;
      font-size: 13px;
      cursor: pointer;
    }

    .shop-buy-btn:disabled {
      opacity: 0.4;
      cursor: not-allowed;
    }

    /* Mobile Controls */
    .mobile-controls {
      display: none;
      position: absolute;
      bottom: 20px;
      left: 0;
      right: 0;
      z-index: 20;
      padding: 0 20px;
      pointer-events: none;
    }

    @media (max-width: 768px) {
      .mobile-controls {
        display: flex;
        justify-content: space-between;
      }
    }

    .touch-btn {
      width: 68px;
      height: 68px;
      border-radius: 50%;
      background: rgba(255, 255, 255, 0.7);
      backdrop-filter: blur(10px);
      border: 3px solid #fff;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 24px;
      color: #0f172a;
      pointer-events: auto;
      box-shadow: 0 8px 20px rgba(0, 0, 0, 0.2);
    }

    .touch-btn:active {
      background: #f97316;
      color: #fff;
      transform: scale(0.92);
    }

    .hidden {
      display: none !important;
    }

    /* Stats Grid */
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 12px;
      margin: 16px 0;
    }

    .stat-box {
      background: #f8fafc;
      border-radius: 18px;
      padding: 14px;
      border: 2px solid #e2e8f0;
    }

    .stat-box-num {
      font-size: 26px;
      font-weight: 900;
      color: #f97316;
    }