code: function isOffsetInEl(x, y, el) {
    var offset = getOffset(el);
    return offset.x <= x && offset.x + el.offsetWidth >= x && offset.y <= y && offset.y + el.offsetHeight >= y;
  }
docs: [isOffsetInEl]
  @param {Number} x
  @param {Number} y
  @param {Object} el HTML Element