Javascript only affects one element

Answer 1

You can use document.getElementsByClassName

JavaScript

var elements = document.getElementsByClassName('item');
for (i =0; i < ele.length; i++)    {
    elements[i].style.borderTop = '1px solid #000';
}

HTML

    
Content 1
    
Content 2
​

​ CSS

#theContainer {
    height: 100px;
    width: 500px;
    position: relative;
    border: 1px solid #900;
    padding: 10px;
}
.item {
    height: 50px;
    width: 100%;
}
​