Hupspot guide to modern CSS nesting

Developers who build sites, themes, or apps that integrate with Hubspot can greatly simplify their stylesheets by using modern CSS nesting. With native nesting now supported in major browsers, you no longer have to rely solely on preprocessors like Sass to keep your CSS organized and readable.

What is CSS nesting and why Hubspot developers should care

CSS nesting lets you place child selectors inside parent rule blocks so related styles stay grouped together. This mirrors the way your HTML is structured, which is especially helpful when you work on complex layouts or reusable modules for Hubspot pages and templates.

Instead of repeating a long selector string over and over, nesting allows you to define a base context and then nest variations inside it. This reduces repetition and makes it easier to maintain larger projects.

How CSS nesting works in modern browsers

Native CSS nesting is defined by the CSS Working Group and has now reached stable support in modern browsers. The syntax looks similar to Sass but has a few critical differences you need to understand before using it on sites that connect to Hubspot tools or APIs.

Basic nested rule structure for Hubspot components

Start with a parent selector, then place related rules inside its block. A typical example for a card component that might be used in a Hubspot landing page could look like this:

.card {  padding: 1rem;  border-radius: 8px;  > h2 {    font-size: 1.5rem;  }  .card-body {    margin-top: 0.5rem;  }}

Here, all nested rules are scoped inside .card, keeping your CSS modular and easier to reason about.

The role of the & nesting selector in Hubspot-friendly CSS

The & symbol represents the full parent selector. You use it whenever the nested rule needs to refer directly to the parent, such as for states, modifiers, or pseudo-classes. This pattern is extremely useful for interactive elements on Hubspot forms and CTAs.

.button {  background: #0054a6;  color: #fff;  &:hover {    background: #003f7d;  }  &--secondary {    background: #e5e5e5;    color: #333;  }}

The nested rules compile to regular CSS selectors, but your source stays compact and easier to maintain.

Key syntax rules Hubspot teams must follow

When adopting CSS nesting in environments that integrate with Hubspot, keep these official syntax rules in mind:

• At least one nested rule inside a block must start with & if the selector would otherwise be ambiguous.
• You can nest type, class, ID, attribute, pseudo-class, and pseudo-element selectors.
• You can also nest at-rules like @media inside existing rules.

Combinators and nesting in Hubspot layouts

For more complex page layouts, such as blog templates or email modules managed near Hubspot workflows, you will often need combinators (like child >, sibling +, or descendant spaces) inside nested rules.

.layout {  display: grid;  gap: 1.5rem;  > .sidebar {    grid-column: 1;  }  > .content {    grid-column: 2;    & + .content {      margin-top: 2rem;    }  }}

This pattern keeps structural logic in one place and works well with modular content systems.

Nesting with media queries in Hubspot projects

Modern CSS nesting lets you move @media rules inside component blocks, which helps keep responsive logic close to the base styles. This is particularly helpful for Hubspot designs that must adapt from desktop marketing pages to mobile visitors.

.hero {  padding: 4rem 2rem;  text-align: center;  @media (min-width: 768px) {    text-align: left;    display: flex;    align-items: center;  }}

The result is the same as placing the media query at the root level, but your component remains self-contained.

CSS nesting vs. Sass nesting for Hubspot developers

If your existing Hubspot themes already rely on Sass, you may wonder whether to migrate to native CSS nesting or use both. While the syntaxes look similar, they are not identical.

• Sass allows more freedom in writing nested selectors without always using &.
• Native CSS nesting is stricter and follows browser standards.
• Some advanced Sass features (like mixins and functions) still require a preprocessor.

In practice, you can gradually update styles to use standard nesting where possible while still compiling Sass for other features often used in custom Hubspot modules.

Common pitfalls when moving Hubspot code to CSS nesting

Watch out for these issues when converting Sass-based Hubspot styles to native nesting:

• Omitted & where the standard requires it.
• Deeply nested selectors that harm performance or readability.
• Accidental changes in selector specificity after refactoring.

Test each refactor carefully across pages tied to Hubspot campaigns, forms, and content templates.

Best practices for scalable nested CSS in Hubspot environments

To keep styles maintainable across marketing sites, apps, and integrations with Hubspot, follow these best practices:

Limit nesting depth

Avoid nesting more than three levels deep. Excessive depth makes selectors overly specific and hard to override, particularly when different Hubspot teams share design systems.

Use clear component-based naming

Pair nesting with a component methodology like BEM. For example:

.nav {  &__item {    list-style: none;  }  &__link {    text-decoration: none;    &:hover {      text-decoration: underline;    }  }}

This pattern works well when synchronizing design systems across Hubspot templates, landing pages, and external microsites.

Keep state rules close to their components

Place hover, focus, active, and aria state styles directly beside their base declarations inside the same nested block. This improves accessibility and makes it easier for teams managing Hubspot content to understand behavior.

Browser support, fallbacks, and Hubspot deployment

Before deploying nested CSS to production sites that integrate with Hubspot, confirm browser support for your audience. Modern evergreen browsers handle nesting, but some older versions may not.

Options for safe rollout include:

• Using a PostCSS plugin to transform nested rules into flat CSS.
• Maintaining a preprocessing pipeline if you already use Sass for Hubspot themes.
• Testing critical templates and forms across target browsers and devices.

If you need a broader implementation strategy that covers performance, accessibility, and marketing automation, consult a technical SEO and implementation partner such as Consultevo.

Learning more about CSS nesting for Hubspot work

To dive deeper into examples, edge cases, and formal syntax, review the detailed guide on CSS nesting directly from the original article that inspired this overview: CSS Nesting Guide. Apply those techniques carefully to your own codebase so your Hubspot implementations stay fast, consistent, and easy to maintain.

By adopting native CSS nesting with disciplined structure and clear naming, teams working with Hubspot can ship cleaner styles, reduce duplication, and retain full control over complex layouts across every marketing and sales touchpoint.