76ff';
          const series = [];
          for (let r=startRow; r<state.rows.length; r++) {
            const v = toNumber(state.rows[r][col]);
            series.push(isNaN(v) ? null : v);
          }
          const transparent = state.chartType === 'line' ? 0.15 : 0.6;
          data.datasets.push({
            label: state.headers[col] || `Column ${col+1}`,
            data: series,
            backgroundColor: alpha(color, transparent),
            borderColor: color,
            pointBackgroundColo