Common CSS Challenges in HubSpot Themes and How to Solve Them

These settings will now appear in the HubSpot Theme Editor.

2. Apply CSS Variables in example.css

Now, use these variables in your CSS file.

✅ Example (example.css):

Now, when users change settings in Theme Editor, styles update dynamically!

Optimising Site Speed

Large CSS files and unused styles can make your website sluggish.

Here’s a simple solution: 

Use tools like PurgeCSS to eliminate unused styles—Minify CSS files with HubSpot’s design manager options. Use reusable classes instead of IDs to reduce redundancy and boost performance.

Identifying CSS Sources for Debugging

Figuring out which CSS rules influence specific elements can be a bit tricky, but it’s part of the learning journey!

Here’s a simple solution:

Feel free to use your browser's developer tools, like Chrome DevTools, to easily inspect elements. By checking the "Computed" tab, you can discover the active CSS rules along with their sources. It’s a great way to experiment with styles directly in the developer tools before committing to any permanent changes in your stylesheet!

1. Optimize Images for Faster Load Times

Steps to Optimize Images:

• Use WebP format instead of PNG/JPG
• Compress images using TinyPNG or ImageOptim
• Resize images to the correct dimensions before uploading
• Enable Lazy Loading to delay loading off-screen images

Example (Lazy Load in HubSpot):

<img src="your-image.webp" loading="lazy" alt="Optimized Image">

HubSpot also provides built-in image resizing using srcset:

<img src="your-image.jpg" alt="Responsive Image">

2. Minify & Combine CSS, JS, and HTML

Large CSS/JS files slow down pages. HubSpot has built-in minification:

Manually combine CSS files to reduce HTTP requests:

<link rel="stylesheet" href="">

3. Reduce Unused CSS & JavaScript

Many themes load unnecessary scripts (e.g., jQuery, animations).

4. Use HubSpot’s CDN for Faster Asset Delivery

HubSpot serves images, fonts, and scripts via CDN (Content Delivery Network)

Always use get_asset_url instead of static file paths

Example:

<link rel="stylesheet" href="">

Handling Responsive Design Challenges

While HubSpot templates are designed with flexibility in mind, they might not always fit perfectly across every device.

Here’s a simple solution:

Consider using CSS Grid or Flexbox for better control over your layouts! Adding custom media queries is a great way to boost responsiveness. Plus, you can take full advantage of HubSpot’s drag-and-drop modules to easily rearrange your content for smaller screens.

Example : 

@media (max-width: 768px) {

  .header-title {

    font-size: 1.5rem;

  }

}

Ensuring Consistent Typography

You might notice that fonts and text sizes can look a bit different from one page to another.

Here’s a simple solution:

Let's define the global typography settings in the HubSpot design manager! It’s a great idea to use relative units like rem and em for scalable font sizes, helping your design adapt beautifully. Also, make sure to specify fallback fonts for a smoother experience across different browsers!

1. Define Global Typography Settings in fields.json

2. Apply CSS Variables for Consistency

Example (example.css)

Optimising Background Images

Sometimes, background images may not quite scale or align the way we'd like them to.

Here’s a simple solution:

You can easily use the background-size property, choosing values like cover or contain, to adjust the scaling of your images. To make sure everything aligns perfectly, just pair it with the background-position property. Also, don't forget to optimize your images before uploading them; this can really help improve your loading times!

Example : 

.background-image {

  background-size: cover;

  background-position: center;

}

Conclusion

HubSpot themes offer fantastic features for developing your website, but they can sometimes bring up a few CSS-related challenges. By following the helpful solutions shared in this blog, you’ll be on your way to creating designs that are consistent, responsive, and high-performing! Don’t forget to make the most of tools like browser developer tools and HubSpot’s resources to simplify your workflow.

If you’ve faced any unique CSS challenges while using HubSpot, I’d love to hear about your experiences in the comments. Let’s team up and tackle these challenges together!

References

1. HubSpot Community
2. Maka Agency – Developer Guide
3. GitHub – HubSpot CMS Theme Boilerplate
4. HubSpot Developers – Performance Guide
5. HubSpot Knowledge Base – Styling
6. HubSpot Academy
7. W3Schools CSS Media Queries
8. CSS Tricks – Typography Guide
9. MDN Web Docs – Background