Work with legacy and simple sites using jQuery selectors, events, AJAX, effects, and plugins.
Lessons
Search descendants and direct children of an element.
find() and children() is easiest to learn by reading the example, changing it, and observing the result.
const $card = $('.start-btn').closest('.card'); // nearest ancestor
$card.find('h3').addClass('highlight'); // descendant search
$card.children('.body').css('color', 'green'); // direct children
$card.siblings().fadeTo(200, 0.5); // sibling elementsPractice the find() and children() example in a small scratch file, then explain what changed and why.