code cleanup

aromacalc/aromacalc.js

@@ -1,7 +1,10 @@
-let buttoncalc = document.getElementById("calculate")
-buttoncalc.addEventListener("click", calculate)
+// let buttoncalc = document.getElementById("calculate")
+// buttoncalc.addEventListener("click", calculate)
 
-function calculate(){
+const calcForm = document.getElementById('calculator')  // const ist hier besser als let, da immutable
+calcForm.addEventListener('submit', calculate)
+
+function calculate(e){
   let aromaamount = document.getElementById("aromaamount").value
   let aromaconc = document.getElementById("aromaconc").value / 100
   let vg = document.getElementById("vg").value
@@ -30,4 +33,6 @@ function calculate(){
     document.getElementById("amountvg").value = amountvg
     document.getElementById("amountpg").value = amountpg
   }
+
+  e.preventDefault()  // https://developer.mozilla.org/en-US/docs/Web/API/Event/preventDefault
 }