theming – How to change the width of a mega-slider?

I use Drupal 7.x. I use the popular theme is port.

Porto comes with a Mega Slider component. And that's what I use here. I'm using the Mega Slider provided with Porto.

I've gone through the tutorial to create a test slider and everything seems to be fine. But the width covers the length of the first page. In the configuration settings of the control, I disabled the check box to allow this width, but this had no effect or change in the display.

I attributed the dimensions of the control to 644 X 320 and I even made sure that every photo used as the main image of each panel had this width. But that does not change anything.

Please advise or ask for more details.