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CSS Framework

What is a CSS framework?

A CSS framework is a front-end framework that contains a set of premade files used for building web projects. It enables developers to create a site structure that follows the best web design practices, without starting from scratch.

Generally, these files include CSS code, but some frameworks feature ready-to-use UI components and JavaScript files for interactive elements.

Types of CSS frameworks

There are various CSS frameworks specializing in different areas. However, they can be largely classified into two groups, based on their complexity:

  • Simple frameworks – the stylesheets only come with a grid system that lets users arrange the website elements in columns
  • Complete frameworks – in addition to the grid, these frameworks feature built-in customizable elements, such as buttons, icons, images, along with their variables

Benefits of using a CSS framework

Using frameworks presents several advantages:

  • It speeds up the process to build web projects
  • It helps maintain a consistent and uniform web design
  • It provides solutions for common front-end web development problems
  • Developers don’t need to rely on designers to create a user-friendly interface
  • Beginners can access help from online forums and docs built around CSS frameworks
  • It eases the creation of responsive design, as most frameworks are built around this aspect

Disadvantages of using a CSS framework

Here are some cons to using frameworks:

  • The learning curve can be steep for certain frameworks
  • Web projects might end up looking similar to one another
  • A framework may contain a lot of code you don’t need, bloating the page size and slowing down the site speed

Should you use a CSS framework?

Whether or not you should use a CSS framework depends on your needs. If you want to create a web project without starting from a blank slate, using frameworks is a great solution.

As such, figure out your needs first and look for a CSS framework that can satisfy them. This way, the framework is optimized for your web projects. 

However, if the project requires a lot of custom configurations, it is best to create your own CSS grid layout.

Here are the most widely-used CSS frameworks on the market:


Bootstrap is a responsive front-end framework that uses a 12-column grid system to create mobile-first websites. 

Based on the flexbox module, the system enables page elements to adjust its height, width, and position to different screen sizes.

The fourth version supports Sass as their preprocessor language, which extends the functionality of CSS code. It also comes with premade UI components, layouts, and templates. 


Foundation is one of the most popular frameworks among well-known brands, like Adobe. Not only can it be used to develop websites, but it can also work for creating emails. 

This framework has a large library of building blocks of UI components. It also offers some starter templates for certain industry categories. 

Additionally, Foundation’s Notable Code feature lets developers upload prototype projects and make notes directly on the websites. 

Semantic UI

Semantic UI is a web development framework that features human-readable HTML. Meaning, it uses descriptive class names that specify what a component does, not how it appears on the interface.

Semantic UI has thousands of theming variables and tools for developing responsive layouts, such as stackable grid containers. It uses LESS as the preprocessor language. 


Bulma is an open-source pure CSS framework. In other words, it doesn’t contain any JavaScript elements. It uses readable class names like Semantic UI. 

Here, the elements are mobile-first by default, which means they are designed for vertical viewing. 

Bulma’s framework is also modular, so developers can download Bulma’s Sass files individually. They don’t have to import files that might not get used. 


Materialize is a framework based on Material Design, which is a design language used in Google products. Like Bootstrap, it uses a responsive 12-column grid system. 

It comes in two versions, one with Sass files and another that only has CSS and JavaScript elements. 

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Olivia is a writer for Zyro and an eCommerce know-it-all. Having spent many years as a retail buyer, she loves writing about trend forecasting, brand building, and teaching others how to optimize online stores for success. She lives in London and spends a lot of time exploring the city’s parks with her whippet.

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