JS-为什么在函数范围之外可以访问此变量？

Question

我有三个事件侦听器，在第三个控制台中，我在前一个事件侦听器中记录了变量。

我认为这不可能，因为变量是函数作用域？

干杯

乔

https://jsfiddle.net/c3wb1vzr/

HTML

<h3>Bill</h3>
£ <input id="billAmount" type="number" placeholder="Bill amount">
<h3>Service</h3>
<select>
            <option>Excellent</option>
            <option>Very Good</option>
            <option>Good</option>
            <option>Ok</option>
            <option>Poor</option>
            <option>Very Poor</option>
        </select>
<h3>How many sharing?</h3>
<input id="totalSharing" type="number" placeholder="Number of people"> people
<button id="calculateTotal">Calculate</button>

JS

document.getElementById('billAmount').addEventListener('input', function(e) {
  var total = e.target.value;
});

document.getElementById('totalSharing').addEventListener('input', function(e) {
  var totalSharing = e.target.value;
});

document.getElementById('calculateTotal').addEventListener('click', function() {
  console.log(totalSharing.value);
});