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

        body {
            font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
            background: linear-gradient(135deg, #FFB74D 0%, #FF9800 100%);
            min-height: 100vh;
            color: #fff;
            overflow-x: hidden;
            user-select: none;
        }

        .game-container {
            max-width: 1200px;
            margin: 0 auto;
            padding: 20px;
            min-height: 100vh;
            display: flex;
            flex-direction: column;
            gap: 20px;
        }

        .game-header {
            text-align: center;
            background: rgba(255, 255, 255, 0.1);
            backdrop-filter: blur(20px);
            border-radius: 20px;
            padding: 25px;
            border: 1px solid rgba(255, 255, 255, 0.2);
        }

        .game-header h1 {
            font-size: 2.5rem;
            font-weight: 300;
            margin-bottom: 10px;
            letter-spacing: 3px;
            text-shadow: 0 2px 10px rgba(0, 0, 0, 0.3);
        }

        .game-subtitle {
            font-size: 1rem;
            opacity: 0.8;
            letter-spacing: 1px;
        }

        .main-interface {
            display: grid;
            grid-template-columns: 300px 1fr 280px;
            gap: 20px;
        }

        .left-panel, .right-panel {
            display: flex;
            flex-direction: column;
            gap: 20px;
        }

        .panel-section {
            background: rgba(255, 255, 255, 0.1);
            backdrop-filter: blur(20px);
            border-radius: 20px;
            padding: 20px;
            border: 1px solid rgba(255, 255, 255, 0.2);
        }

        .panel-section h3 {
            text-align: center;
            margin-bottom: 15px;
            font-weight: 300;
            font-size: 1.2rem;
        }

        .resources-display {
            display: grid;
            grid-template-columns: repeat(2, 1fr);
            gap: 10px;
        }

        .resource-item {
            display: flex;
            align-items: center;
            gap: 10px;
            padding: 10px;
            background: rgba(255, 255, 255, 0.1);
            border-radius: 12px;
        }

        .resource-icon {
            font-size: 1.5rem;
            width: 30px;
            text-align: center;
        }

        .resource-info {
            flex: 1;
        }

        .resource-amount {
            font-weight: 600;
            font-size: 1.1rem;
        }

        .resource-rate {
            font-size: 0.8rem;
            opacity: 0.8;
        }

        .buildings-grid {
            display: grid;
            grid-template-columns: repeat(2, 1fr);
            gap: 10px;
        }

        .building-btn {
            padding: 15px 10px;
            border: none;
            border-radius: 15px;
            background: rgba(255, 255, 255, 0.1);
            color: white;
            cursor: pointer;
            transition: all 0.3s ease;
            text-align: center;
            border: 2px solid transparent;
            display: flex;
            flex-direction: column;
            align-items: center;
            gap: 5px;
        }

        .building-btn:hover {
            background: rgba(255, 255, 255, 0.2);
            transform: translateY(-2px);
        }

        .building-btn.affordable {
            border-color: rgba(76, 175, 80, 0.5);
            background: rgba(76, 175, 80, 0.1);
        }

        .building-btn.disabled {
            opacity: 0.5;
            cursor: not-allowed;
            transform: none;
        }

        .building-icon {
            font-size: 1.5rem;
            margin-bottom: 5px;
        }

        .building-name {
            font-size: 0.8rem;
            font-weight: 600;
            margin-bottom: 3px;
        }

        .building-cost {
            font-size: 0.7rem;
            opacity: 0.8;
        }

        .game-area {
            background: rgba(255, 255, 255, 0.1);
            backdrop-filter: blur(20px);
            border-radius: 20px;
            padding: 20px;
            border: 1px solid rgba(255, 255, 255, 0.2);
            min-height: 500px;
            position: relative;
        }

        .city-grid {
            display: grid;
            grid-template-columns: repeat(8, 1fr);
            grid-template-rows: repeat(6, 1fr);
            gap: 5px;
            height: 100%;
            min-height: 480px;
        }

        .city-tile {
            background: rgba(139, 195, 74, 0.3);
            border-radius: 8px;
            border: 2px solid rgba(255, 255, 255, 0.2);
            cursor: pointer;
            transition: all 0.3s ease;
            display: flex;
            align-items: center;
            justify-content: center;
            position: relative;
            overflow: hidden;
        }

        .city-tile:hover {
            background: rgba(255, 255, 255, 0.2);
            transform: scale(1.05);
        }

        .city-tile.occupied {
            background: rgba(255, 255, 255, 0.2);
            cursor: default;
        }

        .city-tile.occupied:hover {
            transform: none;
        }

        .building-sprite {
            font-size: 2rem;
            filter: drop-shadow(0 2px 4px rgba(0, 0, 0, 0.3));
        }

        .building-level {
            position: absolute;
            top: 2px;
            right: 2px;
            background: rgba(255, 215, 79, 0.9);
            color: #333;
            border-radius: 8px;
            padding: 2px 6px;
            font-size: 0.7rem;
            font-weight: 600;
        }

        .production-display {
            max-height: 200px;
            overflow-y: auto;
        }

        .production-item {
            display: flex;
            justify-content: space-between;
            align-items: center;
            padding: 8px 0;
            border-bottom: 1px solid rgba(255, 255, 255, 0.1);
        }

        .production-item:last-child {
            border-bottom: none;
        }

        .production-building {
            display: flex;
            align-items: center;
            gap: 8px;
        }

        .production-rate {
            font-weight: 600;
            color: #81C784;
        }

        .research-tree {
            display: flex;
            flex-direction: column;
            gap: 10px;
        }

        .research-item {
            padding: 10px;
            background: rgba(255, 255, 255, 0.1);
            border-radius: 12px;
            cursor: pointer;
            transition: all 0.3s ease;
            border: 2px solid transparent;
        }

        .research-item:hover {
            background: rgba(255, 255, 255, 0.2);
        }

        .research-item.completed {
            background: rgba(76, 175, 80, 0.3);
            border-color: rgba(76, 175, 80, 0.5);
        }

        .research-item.researching {
            background: rgba(255, 193, 7, 0.3);
            border-color: rgba(255, 193, 7, 0.5);
            animation: research-pulse 2s ease-in-out infinite alternate;
        }

        @keyframes research-pulse {
            from { opacity: 0.7; }
            to { opacity: 1; }
        }

        .research-name {
            font-weight: 600;
            margin-bottom: 5px;
        }

        .research-desc {
            font-size: 0.8rem;
            opacity: 0.8;
            margin-bottom: 5px;
        }

        .research-cost {
            font-size: 0.7rem;
            color: #FFD54F;
        }

        .achievements-list {
            display: flex;
            flex-direction: column;
            gap: 8px;
            max-height: 150px;
            overflow-y: auto;
        }

        .achievement-item {
            display: flex;
            align-items: center;
            gap: 10px;
            padding: 8px;
            background: rgba(255, 255, 255, 0.1);
            border-radius: 10px;
            transition: all 0.3s ease;
        }

        .achievement-item.unlocked {
            background: rgba(255, 215, 79, 0.3);
            border: 1px solid rgba(255, 215, 79, 0.5);
        }

        .achievement-icon {
            font-size: 1.2rem;
        }

        .achievement-info {
            flex: 1;
        }

        .achievement-name {
            font-size: 0.8rem;
            font-weight: 600;
        }

        .achievement-desc {
            font-size: 0.7rem;
            opacity: 0.8;
        }

        .game-controls {
            display: flex;
            gap: 10px;
            justify-content: center;
            flex-wrap: wrap;
        }

        .btn {
            padding: 10px 20px;
            border: none;
            border-radius: 20px;
            background: #F57C00;
            color: white;
            font-weight: 600;
            cursor: pointer;
            transition: all 0.3s ease;
            font-size: 0.9rem;
            box-shadow: 0 4px 15px rgba(245, 124, 0, 0.3);
        }

        .btn:hover {
            background: #EF6C00;
            transform: translateY(-2px);
            box-shadow: 0 6px 20px rgba(245, 124, 0, 0.4);
        }

        .btn:disabled {
            opacity: 0.5;
            cursor: not-allowed;
            transform: none;
        }

        .btn.start-btn {
            background: #4CAF50;
            box-shadow: 0 4px 15px rgba(76, 175, 80, 0.3);
        }

        .btn.start-btn:hover {
            background: #43A047;
        }

        .btn.secondary {
            background: rgba(255, 255, 255, 0.2);
            box-shadow: 0 4px 15px rgba(255, 255, 255, 0.1);
        }

        .btn.secondary:hover {
            background: rgba(255, 255, 255, 0.3);
        }

        /* 弹窗样式 */
        .popup {
            position: fixed;
            top: 0;
            left: 0;
            right: 0;
            bottom: 0;
            background: rgba(0, 0, 0, 0.8);
            backdrop-filter: blur(10px);
            display: none;
            align-items: center;
            justify-content: center;
            z-index: 1000;
        }

        .popup.show {
            display: flex;
        }

        .popup-content {
            background: linear-gradient(135deg, #FFB74D 0%, #FF9800 100%);
            border-radius: 25px;
            padding: 40px;
            text-align: center;
            max-width: 600px;
            width: 90%;
            box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
            border: 2px solid rgba(255, 255, 255, 0.2);
            max-height: 80vh;
            overflow-y: auto;
        }

        .popup-content h2 {
            font-size: 2rem;
            margin-bottom: 25px;
            font-weight: 300;
        }

        .popup-actions {
            display: flex;
            gap: 15px;
            justify-content: center;
            flex-wrap: wrap;
            margin-top: 20px;
        }

        /* 响应式设计 */
        @media (max-width: 1024px) {
            .main-interface {
                grid-template-columns: 1fr;
                grid-template-rows: auto auto auto;
            }
            
            .left-panel, .right-panel {
                flex-direction: row;
                overflow-x: auto;
            }
            
            .panel-section {
                flex: 0 0 250px;
            }
        }

        @media (max-width: 768px) {
            .game-container {
                padding: 15px;
                gap: 15px;
            }
            
            .game-header h1 {
                font-size: 2rem;
            }
            
            .city-grid {
                grid-template-columns: repeat(6, 1fr);
                grid-template-rows: repeat(8, 1fr);
            }
            
            .resources-display {
                grid-template-columns: 1fr;
            }
            
            .buildings-grid {
                grid-template-columns: 1fr;
            }
        }

        @media (max-width: 480px) {
            .city-grid {
                grid-template-columns: repeat(4, 1fr);
                grid-template-rows: repeat(12, 1fr);
            }
            
            .building-sprite {
                font-size: 1.5rem;
            }
        }

        .tooltip {
            position: absolute;
            background: rgba(0, 0, 0, 0.9);
            color: white;
            padding: 8px 12px;
            border-radius: 8px;
            font-size: 0.8rem;
            pointer-events: none;
            z-index: 1000;
            opacity: 0;
            transition: opacity 0.3s ease;
        }

        .tooltip.show {
            opacity: 1;
        }