To divide a row into columns, you will need to adjust the "Row Layout" (with yellow border) there is a limit in how many columns a row can contain, in this container it only allows 4 columns.
Note: In this layout we cannot specify the size of the columns in percentages or pixels.
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You can use the drop options to set column width based on the number of columns.
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When we hover over the columns we can drag to set the width of the columns.
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In addition there is also a widget that allows us to add an inner section to be able to add more columns.
Note: This only appears when opening the list of widgets in the columns within the row within the section.
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As in "Row Layout" the Inner Row contains the drop options to set column width based on the number of columns.
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Only one inner section level can be allowed.