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There are two ways to add new columns. The simplest way is to duplicate a pre-existing column by clicking the “Copy” button in the side menu bar. Once you have duplicated a column, you can change the widget and element within the new column to create something different.
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You can also add a column within the Row menu. Within the Row menu, select Columns and click “Add a new column.” Do this as many times as you need to achieve the desired number of columns within your Row.
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XS designates how wide your column will be on vertical mobile layouts
SM is the width for horizontal mobile layouts
MD is the column width for vertical tablet layouts
LG represents the width for horizontal tablet and desktop layouts
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Each page is composed of 12 sub-divisions (also called columns, but not to be confused with the Column object you are working with). Each of these sub-divisions represents 1/12 of the horizontal width of the page. 12 boxes creates a column that is 100% the width of the page. 3 boxes creates a column that is 25% the width of the page, so you can have 4 items side by side.
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