问添加了.on('click')的CSS类在第一次事件后不可见

EN

$(document.body).on('click', '.card', function() {
  var currentSelection = $(this)
  var currentSelectionIndex = $(currentSelection).index()

  $(currentSelection).addClass("selected")

  if (currentSelectionIndex !== previousSelectionIndex) {
    p = $("#searchResponse").children().get(previousSelectionIndex)
    $(p).removeClass("selected")
  }

  previousSelectionIndex = currentSelectionIndex;
});