code: function (element) {
          var buffer = element.buffer;
      
          return !(
              this.bottom < (element.top - buffer) || // Element off bottom
              this.top > (element.bottom + buffer) || // Element off top
              this.left > (element.right + buffer) || // Element off left
              this.right < (element.left - buffer)    // Element off right
          );
      }
docs: /*
  Check if element is within viewport
  
  @param [object]: Cached element