问如何从函数外部设置在函数中创建的节点的样式/目标

EN

let container = document.querySelector('.container');
    container.addEventListener('click', () => {
        let createdDiv = document.createElement('div');
        container.appendChild(createdDiv);
        createdDiv.classList.add('div-class');
    })
    
    let someButton= document.querySelector('.someButton');
    someButton.addEventListener('click', () => {
        let divClass = document.querySelector('.div-class');
        divClass.style.backgroundColor = "green";
    })

.container,.someButton{
  border:1px solid black;
  background:grey;
  margin-bottom:4em;
}

.div-class{
  height:40px;
  width:40px;
  border:1px solid red;
}

<div class="container">
  container
</div>


<div class="someButton">
  someButton
</div>

const container = document.querySelector('.container');
// assign sample element to avoid error if new_div is used before assigning.
let newDiv = document.createElement('div'); 

container.addEventListener('click', () => {
    let newDiv = document.createElement('div');
    container.appendChild(newDiv);
    newDiv.classList.add('div-class');
})

newDiv.style = "backgroundColor: green";