For make a row to the fit screen like the below picture you can take the following steps.
1- drag and drop a row shortcode when you are in edit content mode ( Massive Builder )
2- Go to the row's setting
3- please mark the Fit to screen check mark
Now your row has the Fit Screen feature.
You can put the content in the center vertically by marking the "Centered Content".
You can change the vertical position by changing the "Vertical Position" property, For changing the position top, middle, bottom
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