Fix UI issues

frontend/src/components/domain/forecasting/DemandChart.tsx

@@ -377,26 +377,31 @@ const DemandChart: React.FC<DemandChartProps> = ({
                 iconType="line"
               />
 
-              {/* Confidence interval area */}
+              {/* Confidence interval area - rendered as a range between lower and upper bounds */}
               {showConfidenceInterval && (
                 <Area
                   type="monotone"
                   dataKey="confidenceUpper"
-                  stackId={1}
-                  stroke="none"
+                  stroke="#10b981"
+                  strokeWidth={1}
+                  strokeOpacity={0.3}
                   fill="url(#confidenceGradient)"
-                  fillOpacity={0.4}
+                  fillOpacity={0.3}
                   name="Límite Superior"
+                  legendType="none"
                 />
               )}
               {showConfidenceInterval && (
                 <Area
                   type="monotone"
                   dataKey="confidenceLower"
-                  stackId={1}
-                  stroke="none"
-                  fill="#ffffff"
+                  stroke="#10b981"
+                  strokeWidth={1}
+                  strokeOpacity={0.3}
+                  fill="var(--bg-primary, #1a1a2e)"
+                  fillOpacity={1}
                   name="Límite Inferior"
+                  legendType="none"
                 />
               )}