Add counter animations

src/components/AnimatedCounter.jsx

@@ -0,0 +1,34 @@
+import React, { useEffect, useRef, useState } from 'react';
+
+/**
+ * AnimatedCounter
+ * Animates a number from 0 (or start) to the target value progressively.
+ * Usage: <AnimatedCounter value={targetNumber} duration={1000} />
+ */
+function AnimatedCounter({ value, duration = 1000, start = 0, format = v => v }) {
+  const [displayValue, setDisplayValue] = useState(start);
+  const rafRef = useRef();
+  const startRef = useRef(start);
+  const valueRef = useRef(value);
+
+  useEffect(() => {
+    startRef.current = displayValue;
+    valueRef.current = value;
+    let startTime;
+    function animate(ts) {
+      if (!startTime) startTime = ts;
+      const progress = Math.min((ts - startTime) / duration, 1);
+      const current = Math.round(startRef.current + (valueRef.current - startRef.current) * progress);
+      setDisplayValue(current);
+      if (progress < 1) {
+        rafRef.current = requestAnimationFrame(animate);
+      }
+    }
+    rafRef.current = requestAnimationFrame(animate);
+    return () => cancelAnimationFrame(rafRef.current);
+  }, [value, duration]);
+
+  return <span>{format(displayValue)}</span>;
+}
+
+export default AnimatedCounter;