           // Transport mode colors
            const transportColors = {
                'DRIVING': '#FF6384',
                'WALKING': '#36A2EB',
                'CYCLING': '#FFCE56',
                'public_transport': '#4BC0C0',
                'unknown': '#FF9F40'
            };

            // Render pie chart for month transport distribution
            if (transportStats.length > 0) {
                const pieCanvas = document.getElementById(`monthTransportPieChart_${year}_${month}`);
            