As specified, an author can change the number of columns and the border color by using the column's dialog.
This development article walks you through how to build this custom column component. To read this development article, click https://helpx.adobe.com/experience-manager/using/custom_columns.html.
NOTE - This artilce is for the Classic UI. Its recommended that you use Touch UI. See this article -- http://scottsdigitalcommunity.blogspot.ca/2017/09/creating-custom-touch-ui-grid-component.html.
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I (Scott Macdonald) am a Senior Digital Marketing Community Manager at Adobe Systems with 20 years in the high tech industry. I am also a programmer with knowledge in Java, JavaScript, C#,C++, HTML, XML and ActionScript. If you would like to see more CQ or other Adobe Digital Marketing end to end articles like this, then leave a comment and let me know what content you would like to see.
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