The column-gap CSS property sets the size of the gap between columns for elements which are specified to display as a multi-column element.


Is a keyword indicating to use the browser-defined default spacing between columns. The specification, and most modern browsers follow it, recommends this keyword to be equal to a length of 1em.
Is a <length> value defining the size of the gap between columns. It must not be negative, but may be equal to 0.

<!DOCTYPE html>
.myCSSStyle {
	-moz-column-count:4; /* Firefox */
	-webkit-column-count:4; /* Safari and Chrome */
	column-count: 4;
	-moz-column-gap:40px; /* Firefox */
	-webkit-column-gap:40px; /* Safari and Chrome */
<p><b>Note:</b> Internet Explorer and Firefox do not support the columns
<div class="myCSSStyle"> 
On the Insert tab, the galleries include items that are designed 
  to coordinate with the overall look of your document. You can use 
  these galleries to insert tables, headers, footers, lists, cover 
  pages, and other document building blocks.
  When you create pictures, charts, or diagrams, they also coordinate
  with your current document look.You can easily change the formatting
  of selected text in the document text by choosing a look for the 
  selected text from the Quick Styles gallery on the Home tab. You can 
  also format text directly by using the other controls on the Home tab. 
  Most controls offer a choice of using the look from the current 
  theme or using a format that you specify directly.
  To change the overall look of your document, choose new Theme elements 
  on the Page Layout tab. To change the looks available in the Quick 
  Style gallery, use the Change Current Quick Style Set command. Both 
  the Themes gallery and the Quick Styles gallery provide reset 
  commands so that you can always restore the look of your document 
  to the original contained in your current template. </div>