* { margin: 0; padding: 0; box-sizing: border-box; }
        body { 
            font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif; 
            background: linear-gradient(135deg, #1e3c72 0%, #2a5298 100%); 
            min-height: 100vh; 
            padding: 20px; 
        }
        .container { 
            max-width: 1200px; 
            margin: 0 auto; 
            background: white; 
            border-radius: 15px; 
            box-shadow: 0 15px 50px rgba(0,0,0,0.2); 
            overflow: hidden; 
        }
        .header { 
            background: linear-gradient(135deg, #667eea 0%, #764ba2 100%); 
            color: white; 
            padding: 25px; 
            text-align: center; 
        }
        .main-content { 
            display: grid; 
            grid-template-columns: 1fr 1fr; 
            gap: 25px; 
            padding: 25px; 
        }
        .section { 
            background: #f8f9fa; 
            border-radius: 10px; 
            padding: 20px; 
            border: 2px solid #e9ecef; 
        }
        .section h2 { 
            color: #2c3e50; 
            margin-bottom: 15px; 
            font-size: 1.4rem; 
            border-bottom: 2px solid #3498db; 
            padding-bottom: 8px; 
        }
        .input-group { margin-bottom: 15px; }
        .input-group label { 
            display: block; 
            margin-bottom: 5px; 
            font-weight: 600; 
            color: #34495e; 
        }
        .input-group input, .input-group select { 
            width: 100%; 
            padding: 10px; 
            border: 2px solid #ddd; 
            border-radius: 6px; 
            font-size: 14px; 
            transition: border-color 0.3s;
        }
        .input-group input:focus, .input-group select:focus {
            border-color: #3498db;
            outline: none;
        }
        .dimensions-grid { 
            display: grid; 
            grid-template-columns: 1fr 1fr 1fr; 
            gap: 10px; 
        }
        .btn { 
            background: #27ae60; 
            color: white; 
            border: none; 
            padding: 12px 20px; 
            border-radius: 6px; 
            font-weight: 600; 
            cursor: pointer; 
            width: 100%; 
            margin-top: 10px; 
            transition: all 0.3s; 
            font-size: 14px;
        }
        .btn:hover { 
            background: #229954; 
            transform: translateY(-1px);
        }
        .btn:active {
            transform: translateY(0);
        }
        .btn-secondary { background: #3498db; }
        .btn-secondary:hover { background: #2980b9; }
        .btn-danger { background: #e74c3c; }
        .btn-danger:hover { background: #c0392b; }
        .btn-warning { background: #f39c12; }
        .btn-warning:hover { background: #e67e22; }
        .btn-grid { 
            display: grid; 
            grid-template-columns: 1fr 1fr; 
            gap: 10px; 
        }
        .stock-table { 
            width: 100%; 
            border-collapse: collapse; 
            margin-top: 10px; 
            background: white; 
            border-radius: 6px; 
            overflow: hidden; 
            font-size: 0.9rem; 
        }
        .stock-table th, .stock-table td { 
            padding: 8px; 
            text-align: left; 
            border-bottom: 1px solid #ddd; 
        }
        .stock-table th { 
            background: #34495e; 
            color: white; 
            font-weight: 600; 
            position: sticky;
            top: 0;
            z-index: 10;
        }
        .stock-table tr:hover { 
            background: #f1f2f6; 
        }
        .stock-container { 
            max-height: 250px; 
            overflow-y: auto; 
            border: 1px solid #ddd; 
            border-radius: 6px; 
        }
        .result-section { 
            grid-column: 1 / -1; 
            margin-top: 20px; 
        }
        .result-grid { 
            display: grid; 
            grid-template-columns: 2fr 1fr 1fr; 
            gap: 20px; 
            margin-top: 15px; 
        }
        .wall-visualization { 
            background: white; 
            border: 2px solid #ddd; 
            border-radius: 8px; 
            padding: 15px; 
            min-height: 300px; 
            position: relative; 
        }
        .block { 
            position: absolute; 
            border: 1px solid #333; 
            display: flex; 
            align-items: center; 
            justify-content: center; 
            font-size: 9px; 
            font-weight: 600; 
            color: white; 
            text-shadow: 1px 1px 1px rgba(0,0,0,0.5); 
            cursor: pointer; 
            transition: all 0.2s;
        }
        .block:hover {
            transform: scale(1.05);
            z-index: 1000;
            box-shadow: 0 4px 12px rgba(0,0,0,0.3);
        }
        .stats { 
            background: #e8f5e8; 
            border: 2px solid #27ae60; 
            border-radius: 8px; 
            padding: 15px; 
        }
        .stat-item { 
            display: flex; 
            justify-content: space-between; 
            margin-bottom: 8px; 
            padding: 5px 0; 
            border-bottom: 1px solid #ccc; 
        }
        .alert { 
            padding: 12px; 
            border-radius: 6px; 
            margin: 10px 0; 
        }
        .alert-success { 
            background: #d4edda; 
            border: 1px solid #c3e6cb; 
            color: #155724; 
        }
        .alert-warning { 
            background: #fff3cd; 
            border: 1px solid #ffeaa7; 
            color: #856404; 
        }
        .alert-danger { 
            background: #f8d7da; 
            border: 1px solid #f5c6cb; 
            color: #721c24; 
        }
        .alert-info {
            background: #d1ecf1;
            border: 1px solid #bee5eb;
            color: #0c5460;
        }
        .cursor {
            position: absolute;
            width: 2px;
            height: 2px;
            background: red;
            display: none;
            z-index: 10;
            pointer-events: none;
        }
        .loading {
            display: inline-block;
            width: 20px;
            height: 20px;
            border: 3px solid #f3f3f3;
            border-top: 3px solid #3498db;
            border-radius: 50%;
            animation: spin 1s linear infinite;
        }
        @keyframes spin {
            0% { transform: rotate(0deg); }
            100% { transform: rotate(360deg); }
        }
        .progress-bar {
            width: 100%;
            height: 20px;
            background: #f0f0f0;
            border-radius: 10px;
            overflow: hidden;
            margin: 10px 0;
        }
        .progress-fill {
            height: 100%;
            background: linear-gradient(90deg, #27ae60, #2ecc71);
            transition: width 0.3s ease;
        }
        .tooltip {
            position: absolute;
            background: rgba(0,0,0,0.8);
            color: white;
            padding: 8px 12px;
            border-radius: 4px;
            font-size: 12px;
            z-index: 1001;
            pointer-events: none;
            white-space: nowrap;
        }
        @media (max-width: 1000px) {
            .main-content, .result-grid { grid-template-columns: 1fr; }
            .btn-grid { grid-template-columns: 1fr; }
            .dimensions-grid { grid-template-columns: 1fr 1fr; }
        }
        @media (max-width: 600px) {
            .dimensions-grid { grid-template-columns: 1fr; }
            .container { margin: 10px; }
            .main-content { padding: 15px; }
        }