diff --git a/pages/css/devis.js b/pages/css/devis.js
new file mode 100644
index 0000000..6487e7b
--- /dev/null
+++ b/pages/css/devis.js
@@ -0,0 +1,34 @@
+const affichageNb = document.getElementById("nb_vehicules");
+const affichageGéo = document.getElementById("géolocalisation");
+const affichageConso = document.getElementById("consommation");
+const boutonPlus = document.getElementById("plus");
+const boutonMoins = document.getElementById("moins");
+const PRIX_GPS = 30;
+const PRIX_CONSOMMATION = 15;
+let nbVehicules = 1;
+let totalargent = 0;
+function mettreAJourGPS() {
+  affichageNb.textContent = nbVehicules;
+  affichageGéo.textContent = nbVehicules * PRIX_GPS;
+}
+function mettreAJourCONSO() {
+  affichageNb.textContent = nbVehicules;
+  affichageConso.textContent = nbVehicules * PRIX_CONSOMMATION;
+}
+function mettreAJourTOTAL() {
+  affichageNb.textContent = totalargent;
+  affichageGéo.textContent = totalargent + PRIX_GPS + PRIX_CONSOMMATION;
+}
+boutonPlus.addEventListener("click", function () {
+  nbVehicules = nbVehicules + 1;
+  (mettreAJourGPS(), mettreAJourCONSO());
+  if (nbVehicules > 99) {
+    nbVehicules = nbVehicules - 1;
+  }
+});
+boutonMoins.addEventListener("click", function () {
+  if (nbVehicules > 1) {
+    nbVehicules = nbVehicules - 1;
+  }
+  (mettreAJourGPS(), mettreAJourCONSO());
+});