Blogs by date "April 2015"

Theming with Twitter Bootstrap version 3 - Part 3

Twitter Bootstrap 3(Corrected May 5, 2014) Recently, Google changed the way they rank search hits by elevating those from 'mobile friendly' web sites and lowering those which are not mobile friendly.  To be 'mobile friendly' your web site must conform to modern standards (HTML5) AND must be small device and 'touch friendly' ...meaning the page is viewable on a small screen and the buttons/links have some space/distance between them for 'fat fingers.  The easiest way to make your Exponent CMS site 'mobile friendly' is to switch or update to a Twitter Bootstrap 3 based theme.  Exponent CMS allows you to do this in just a matter of minutes.

The easiest (and most obvious)  method is to simply switch to the included 'bootstrap3theme'.  This would immediately ensure your web site is 'mobile friendly.'  In most cases, the content of you web site will remain unchanged, though some custom theme elements in the header, footer, and sidebar may not appear if you were using a non-standard 'source' name within the previous custom theme.  In its stock form, the bootstrap3theme is well, plain.

The next level of customization would be to 'customize' the shipped theme using the 'Configure' button found with the theme on the 'Manage Themes' page.  

  • We offer a dozen or so different theme styles which offer a variety of colors, fonts, and styles
  • You could spice up the look with some 'flair' to the widgets by selecting the 'Bootstrap v2 Styles' setting which will give them a slight 3d effect
  • You could choose a 'fluid' width which would make the content fill almost the entire width of the display or browser width.  'Fixed' width limits the overall width of the content.
  • You can also select the 'size' of the buttons, location of the main menu (navbar), whether the navbar is aligned to the left or right side of the page, whether the flyout sidebar container is displayed, and a couple of tweaks to adjust how the main navbar is displayed.

The only drawbacks thus far are: 1) the theme and its 'configuration' will be overwritten the next time you update the site software with a new version since you are using a 'shipped theme', and 2) the basic Twitter Bootstrap themes are somewhat lacking in 'flash'.

Therefore the next level of customization would be to create a custom version of the shipped bootstrap3theme.  The documentation for creating a custom theme is found here.  A quick overview would be  to copy the entire /themes/bootstrap3theme folder into a new folder with a different name.  We'll say 'customtheme' for example and ensure we update the new custom theme's 'class.php' file to reflect the new theme's real name.  Once this complete, you'll need to select your new 'customtheme' from the Manage Themes page.  At this point your site will be identical to the previous step, but will not longer be in jeopardy of replacement when updating the site software version.  If you want to place the custom theme swatch files within your custom theme for further customization, you will need to:

  • Copy the .less files from the selected theme style which is found in /external/bootstrap3/less/'theme style name'.  You should find two files here...variables.less and bootswatch.less
  • WARNING! You MUST edit the new variables.less file which will fill in any missing, but essential variables:
    • Add the following line to the TOP of the new custom variables.less file
      • @import "../../../external/bootstrap3/less/variables.less";
    • The 'merge' the contents of the existing 'variables.less' file to the BOTTOM of the custom theme variables.less file to ensure any custom navbar 'collapse' width is followed.  
  • NEXT you MUST also insert the following line at the top of the 'bootswatch.less' file to get it to compile correctly
    • @import "variables.less";
  • Then if you want to make some subtle color changes, you can use a site like which will let you copy in your 'variables.less' file and allow you to edit it with instant feedback on color changes.

That's it, you now have a custom 'mobile friendly' web site.  Next time we'll dig a bit more deeply (and spend more time) to customize the theme to look 'less plain.'

About the author

Dave Leffler
Exponent CMS Developer