It works, but sometimes it stops when I click on a button
<p>my code basically works, but when I click the start button a few times, so for example I click on start, the randomnumbers appear, then I type in a number, click on fertig, and make these steps for a few times again. After these few times the start button is "stuck" when I click on it. So I click on it, it goes down, but not up again, you understand ? :-)</p>

<p>Here's the HTML:</p>

<pre><code>&lt;!DOCTYPE html&gt;
&lt;html&gt;



 &lt;head&gt;
  &lt;meta charset="utf-8"&gt;
  &lt;title&gt;Der Einmaleins - Trainer&lt;/title&gt;  
  &lt;link href = "style.css" type = "text/css" rel = "stylesheet"&gt;
  &lt;script src = "script1m1.js"&gt;&lt;/script&gt;
 &lt;/head&gt;
 &lt;body&gt;
  &lt;h1&gt;Der Einmaleins - Trainer&lt;/h1&gt; 
  &lt;button type="button" onclick = "start();"&gt;Start&lt;/button&gt; 
  &lt;button type = "button" onclick = "fertig();"&gt;Fertig!&lt;/button&gt;
  &lt;input id = "erginput" type = "number"&gt;

  &lt;label id = "rn1"&gt;&lt;/label&gt;  
  &lt;label id = "multiplication"&gt;&lt;/label&gt;
  &lt;label id = "rn2"&gt;&lt;/label&gt;  
  &lt;br&gt;
  &lt;label id = "feedback"&gt;&lt;/label&gt;


 &lt;/body&gt;

&lt;/html&gt; 
</code></pre>

<p>Here's the JS:</p>

<pre><code>var randomnumber1;
var randomnumber2;

function start() {  
  randomnumber1 = getrn();
  randomnumber2 = getrn();
  while(randomnumber1 == 5 || randomnumber2 == 5 ){
     if (randomnumber1 == 5){randomnumber1 = getrn();}
     else{randomnumber2 == getrn();}

}
document.getElementById("rn1").innerHTML = randomnumber1;
document.getElementById("multiplication").innerHTML = "x";
document.getElementById("rn2").innerHTML = randomnumber2;

}

function getrn(){
  var min = 3;
  var max = 10;
  var zufallszahl = Math.floor(Math.random() * (max - min)) + min;
 return zufallszahl;
}

function ergebnispruefen(zahl,faktor1,faktor2){
  var ergebnisrichtig = faktor1 * faktor2;
  if (zahl == ergebnisrichtig){
       document.getElementById("feedback").innerHTML = "Richtig!";
       document.getElementById("feedback").style.color = "Lime";
  }else{
       document.getElementById("feedback").innerHTML = "Falsch,denk  nach!";
     document.getElementById("feedback").style.color = "red";
}

}

function fertig(){
  var ergebnis = document.getElementById("erginput").value;  
  ergebnispruefen(ergebnis,randomnumber1,randomnumber2);

}
</code></pre>

<p>console.log("Thanks in advance! :-)");</p>

<p>Ji W</p>