Let’s understand Row settings. Click the blue button next to the row to change its settings. A dialog box will open in front of you:
As you can see in this dialog box, the fields of CSS class and custom style are present. You can apply a CSS class or a CSS style through these fields. It also has two other fields “Container Width” and “Content Stretch”. It is very important to understand their effect.
As you can see in the given figure, keeping the width of the container “normal” leaves it side by side and content locates in the center. Whereas when the width of the container is “full width” it covers the entire screen.
If the content stretch is kept “normal” once the container width is surrounded by the screen, the column and their widgets etc. remain in the center. Whereas if the content stretches are turned on, they take up the whole screen.