By default blog and posts page is set to be 3/4 (75%) width for the body section and 1/4 (25%) width for the sidebar section, but this may not be ideal for your layout. You may see a lot of text wrap if you have longer category names or are displaying latest blog posts in the sidebar and prefer to give them a little extra space.
If you want to change the default sidebar width on your blog and posts page you can use the Divi Theme Customizer settings to specify what percentage width it should be.
Steps to change the Divi sidebar
Change the sidebar width using the Theme Customizer:
- In the WordPress dashboard go to Divi > Theme Customizer or Appearance > Customize
- Click on the General Settings > Layout Settings
- Check the Use Custom Sidebar Width check-box and the sidebar width option slider will appear
- Drag the slider or use the text box to set the Sidebar Width (The number is a percentage of the content width, which is 1080 px on a desktop by default)
- Publish the changes and your sidebar width will be as you set it