fix: effet ambiance tildes → bulles (° au lieu de ~)

Frontend/src/pages/Home.jsx

@@ -37,7 +37,7 @@ export default function Home() {
   useEffect(() => {
     const rain = {
       wind: 0, maxXrange: 40, minXrange: 20, maxSpeed: 1, minSpeed: 3,
-      color: "#8ecae6", char: "~", maxSize: 32, minSize: 10,
+      color: "#8ecae6", char: "°", maxSize: 28, minSize: 8,
       flakes: [], WIDTH: -10, HEIGHT: 0, running: false,
       init(nb) {
         const frag = document.createDocumentFragment();