Function isNodeName

scripts/smoothScroll.js:708–710

(el, tag)

    window.removeEventListener(type, fn, arg || false);
  }
  function isNodeName(el, tag) {
    return el && (el.nodeName || "").toLowerCase() === tag.toLowerCase();
  }
  function directionCheck(x, y) {
    x = x > 0 ? 1 : -1;
    y = y > 0 ? 1 : -1;