2020.1

The closest() command is based on the closest() command found in the jQuery library:
https://api.jquery.com/closest/.
closest(selector)
For one HTML element or for each element in a set, this function gets the first element that
matches the selector by testing the element itself and traversing up through its ancestors in the
DOM tree.
selector
A String containing an HTML tag (without the angle brackets, <>).
Examples
The following script looks up all table rows in the template that contain an <input> element.
query("input").closest("tr");
This code gets the closest 'parent' row for each element that matches the selector of the script
(collected in the results object):
results.closest("tr");
The rows could be colored red within the same statement:
results.closest("tr").css('background-color','red');
css()
Gets the value of a style property of one HTML element, or sets one or more CSS properties of
one or more HTML elements.
css(styleName) : String
Returns the value of the specified CSS property of an HTML element, which can be:
l The first element in a set of elements that match the selector of a script (see "results" on
page909).
l One element that matches the selector of a script that runs for "Each matched element"
(see "this" on page834 and "Setting the scope of a script" on page383).
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