Give users a latest visual style that makes it easier to focus and navigate.
Salesforce has launched its Salesforce Cosmos theme for SLDS 2 (beta) in Spring ’25.
SLDS 2 is a complete redesign and refinement of SLDS 1 (launched in 2015) with improvement focused on:
- Modern Visual style & easy navigation
- Improved Page load speed
- Cleaner UI Components & Optimized CSS
- Improved accessibility & responsiveness
Why it matters:
Advantages
- Modern Look & Feel: Cosmos offers a sleek, cleaner interface, improving user focus and reducing visual clutter.
- Improved Accessibility: Better contrast ratios and accessible components out of the box
- Better Performance: More lightweight CSS and optimized components in SLDS 2
Disadvantages
- Learning Curve: Developers need to adapt to new Components and Design pattern of SLDS 2
- Migration Effect: Existing Org may require rework to align with SLDS 2.
- Limited Backward Compatibility: Some older SLDS1 Customizations may not transfer easily to SLDS 2.
You can experience the enhancements in the visual style of the Lightning UI.
Here are the steps to enable the Salesforce Cosmos theme in your Org.
- Log in to your Salesforce Org – Use Sandbox or Developer Org (recommended for Testing before enabling it in Production).
- Go to Setup – Click on gear icon (top right corner)
- Search for “Themes and Branding” in quick find. Themes and Branding is part of User Interface.
- Look for the Salesforce Cosmos theme on the Theme page
- Salesforce Cosmos theme dropdown list, Click Activate.
Once the Salesforce Cosmos SLDS 2 theme is activated, the Salesforce Lightning UI is going to be change.
Complete guidebook to get your Salesforce org up and running with the latest upgrade for SLDS 2.
Transition to SLDS 2
Please Note: Cosmos Theme is still in Beta phase, so it is recommended to test thoroughly in Sandbox before enabling in Production.
We can still access the SLDS 1 content at http://v1.lightningdesignsystem.com
Nice guide on enabling the Salesforce Cosmos theme! The steps seem straightforward and easy to follow. Changing to the Cosmos theme should provide a fresh UI experience. Subscribing to the newsletter sounds like a great way to stay updated.
Will this theme update affect existing UI customizations?
This is not just theme update, but moving From SLDS 1 to SLDS 2 (Salesforce Lightning Design System) a CSS-based styling enhancement, so the Salesforce Platform, as well as other features, are not impacted. When you are looking forward to continuing to create dynamic, scalable, and tailored experiences on the Lightning Platform, SLDS 2 will become a valuable tool.