fix: improve dark mode compatibility and chart visibility

- Fix TopQuestionsChart with proper dark mode colors using CSS variables and shadcn/ui components
- Enhance ResponseTimeDistribution with thicker bars (maxBarSize: 60)
- Replace GeographicMap with dark/light mode compatible CartoDB tiles
- Add custom text selection background color with primary theme color
- Update all loading states to use proper CSS variables instead of hardcoded colors
- Fix dashboard layout background to use bg-background instead of bg-gray-100

components/magicui/confetti.tsx

@@ -0,0 +1,149 @@
+"use client";
+
+import type {
+  GlobalOptions as ConfettiGlobalOptions,
+  CreateTypes as ConfettiInstance,
+  Options as ConfettiOptions,
+} from "canvas-confetti";
+import confetti from "canvas-confetti";
+import type { ReactNode } from "react";
+import React, {
+  createContext,
+  forwardRef,
+  useCallback,
+  useEffect,
+  useImperativeHandle,
+  useMemo,
+  useRef,
+} from "react";
+
+import { Button, ButtonProps } from "@/components/ui/button";
+
+type Api = {
+  fire: (options?: ConfettiOptions) => void;
+};
+
+type Props = React.ComponentPropsWithRef<"canvas"> & {
+  options?: ConfettiOptions;
+  globalOptions?: ConfettiGlobalOptions;
+  manualstart?: boolean;
+  children?: ReactNode;
+};
+
+export type ConfettiRef = Api | null;
+
+const ConfettiContext = createContext<Api>({} as Api);
+
+// Define component first
+const ConfettiComponent = forwardRef<ConfettiRef, Props>((props, ref) => {
+  const {
+    options,
+    globalOptions = { resize: true, useWorker: true },
+    manualstart = false,
+    children,
+    ...rest
+  } = props;
+  const instanceRef = useRef<ConfettiInstance | null>(null);
+
+  const canvasRef = useCallback(
+    (node: HTMLCanvasElement) => {
+      if (node !== null) {
+        if (instanceRef.current) return;
+        instanceRef.current = confetti.create(node, {
+          ...globalOptions,
+          resize: true,
+        });
+      } else {
+        if (instanceRef.current) {
+          instanceRef.current.reset();
+          instanceRef.current = null;
+        }
+      }
+    },
+    [globalOptions],
+  );
+
+  const fire = useCallback(
+    async (opts = {}) => {
+      try {
+        await instanceRef.current?.({ ...options, ...opts });
+      } catch (error) {
+        console.error("Confetti error:", error);
+      }
+    },
+    [options],
+  );
+
+  const api = useMemo(
+    () => ({
+      fire,
+    }),
+    [fire],
+  );
+
+  useImperativeHandle(ref, () => api, [api]);
+
+  useEffect(() => {
+    if (!manualstart) {
+      (async () => {
+        try {
+          await fire();
+        } catch (error) {
+          console.error("Confetti effect error:", error);
+        }
+      })();
+    }
+  }, [manualstart, fire]);
+
+  return (
+    <ConfettiContext.Provider value={api}>
+      <canvas ref={canvasRef} {...rest} />
+      {children}
+    </ConfettiContext.Provider>
+  );
+});
+
+// Set display name immediately
+ConfettiComponent.displayName = "Confetti";
+
+// Export as Confetti
+export const Confetti = ConfettiComponent;
+
+interface ConfettiButtonProps extends ButtonProps {
+  options?: ConfettiOptions &
+    ConfettiGlobalOptions & { canvas?: HTMLCanvasElement };
+  children?: React.ReactNode;
+}
+
+const ConfettiButtonComponent = ({
+  options,
+  children,
+  ...props
+}: ConfettiButtonProps) => {
+  const handleClick = async (event: React.MouseEvent<HTMLButtonElement>) => {
+    try {
+      const rect = event.currentTarget.getBoundingClientRect();
+      const x = rect.left + rect.width / 2;
+      const y = rect.top + rect.height / 2;
+      await confetti({
+        ...options,
+        origin: {
+          x: x / window.innerWidth,
+          y: y / window.innerHeight,
+        },
+      });
+    } catch (error) {
+      console.error("Confetti button error:", error);
+    }
+  };
+
+  return (
+    <Button onClick={handleClick} {...props}>
+      {children}
+    </Button>
+  );
+};
+
+ConfettiButtonComponent.displayName = "ConfettiButton";
+
+export const ConfettiButton = ConfettiButtonComponent;