1$( "li.item-a" )
2  .closest( "ul" )
3  .css( "background-color", "red" );
4

1$( "li.item-a" )
2  .closest( "ul" )
3  .css( "background-color", "red" );

1$( this ).closest( "form" )

1$(".isActive").click(function() {
2    var div_id = $(this).closest('tr').find('.display_image').attr(id);
3    // ...
4});
5

1Closest 
2
3<div class="product">
4  <div class="product-counter">
5     <div class="input-group-append">
6
7       <div class="input-group-append">
8         <button class="btn btn-outline-primary product-minus" type="button"> <i class="fas fa-minus"></i> </button>
9       </div>
10
11       <input type="text" class="form-control product-number" placeholder="1" value="1">
12
13       <div class="input-group-append">
14          <button class="btn btn-outline-primary product-plus" type="button"> <i class="fas fa-plus"></i> </button>
15       </div>
16    </div>
17  </div>   
18  <button class="btn btn-light product-order"> Order + </button>
19</div>
20
21------ 
22ex: i am at .product-order
23 
24$(document).on('click', '.product-order', function(e) {
25
26  var counter = $(this).closest('div').find('.product-counter');
27  var number = $(this).closest('div.product').find('.product-number');
28  var minus = $(this).closest('div.product').find('.product-minus');
29  var plus = $(this).closest('div.product').find('.product-plus');
30  
31});
32

1// Find the number from `arr` which is closest to `n`
2const closest = (arr, n) => arr.reduce((prev, curr) => Math.abs(curr - n) < Math.abs(prev - n) ? curr : prev);
3
4// Or
5const closest = (arr, n) => arr.sort((a, b) => Math.abs(a - n) - Math.abs(b - n))[0];
6
7// Example
8closest([29, 87, 8, 78, 97, 20, 75, 33, 24, 17], 50);   // 33