Design Tokens and Component Based Design

This content originally appeared on 24 ways and was authored by Drew McLellan

Stuart Robson rolls up his sleeves and begins to piece together the jigsaw puzzle that is design tokens and component based design. Starting with the corners, and working around the edges, Stu helps us to piece together a full picture of a modern design system.

If you stare at your twitter feed long enough, it can look like everyone is talking about Design Systems. In some cases you could be persuaded to think how shallow the term can go.

“Isn’t this what we called Style Guides?”, “Here’s my React Design System”, “I’ve just updated the Design System in Sketch”

To me, they are some and all of these things. Over the last 4 years of consulting with two clients on their Design System, my own view has changed a little.

If you dig a little deeper into Design Systems twitter you will probably see the term “Design Tokens” pop up at least once a day somewhere. Design Tokens came out of work that was being done at Salesforce with Jina and others who pioneered the creation of Design Tokens as we know them today – creating the first command line tool in Theo that had started the adoption of Design Tokens to the wider Design Systems Community.

A cool term but, what are they?

If you look at your client work, your companies site, the project you’re working on you should notice some parts of the page have a degree of consistency: the background colour of your form buttons is the same colour as your link text, or your text has the same margin, or your card elements have the same spacing as your media object.

These are design decisions, and they should be littered across the overall design of your project. These decisions might start off in a Sketch file and make their way into code from detailed investigation of a Sketch file, or you may find that the design evolves from your design application once it gets into code.

These design decisions can change, and to keep them synchronised across design and development in applications, as well as a larger documentation site in your Design System, is going to take some effort.

This is where Design Tokens come in, and I find the best way to succinctly reiterate what they are is via the two following quotes…

“Design Tokens are an abstraction for everything impacting the visual design of an app/platform.”
– Sönke Rohde

…and

“We use them in place of hard-coded values in order to maintain a scale-able and consistent visual system.”
– Jina

There are several global design decisions that we can abstract to create a top level design token – Sizing, Font Families, Font Styles, Font Weights, Font Sizes, Line Heights, Border Styles, Border Colours, Border Radius, Horizontal Rule Colours, Background Colours, Gradients, Background Gradients, Box Shadows, Filters, Text Colours, Text Shadow, Time, Media Queries, Z Index, Icons – these can all be abstracted as required.

So, spicy Sass variables?

We can look at Design Tokens as an abstraction of CSS, sort of like Sass variables, but spicier. Looking at them like this we can see that they are (in either .yaml or .json) a group of related key value pairs with more information that can be added as needed.

The great thing with abstracting design decisions outside of your CSS pre-processor is that you’re not tying those decisions to one platform or codebase.

As a crude example, we can see here that we are defining a name and a value that could then become our color, background-color, or border-color, and more.

# Colours
# -------
- name: color-red
  value: #FF0000
- name: color-green
  value: #00FF00
- name: color-blue
  value: #0000FF
- name: color-white
  value: #FFFFFF
- name: color-black
  value: #000000

These can then generate our Sass variables (as an example) for our projects.

$color-red: #FF0000 !default;
$color-green: #00FF00 !default;
$color-blue: #0000FF !default;
$color-white: #FFFFFF !default;
$color-black: #000000 !default;

Why are they so good

Ok, so we now know what Design Tokens are, but why do we need them? What makes them better than our existing solutions (css pre-processors) for defining these design decisions?

I think there are 5 really good reasons why we all should start abstracting these design decisions away from the CSS that they may live in. Some of these reasons are similar to reasons some developers use a pre-processor like Sass, but with added bonuses.

Consistency

Much like using a CSS pre-processor or using CSS custom properties, being able to define a background colour, breakpoint, or font-size in more than one place using the same key ensures that we are using the Sass values across the entire product suite we are developing for.

Using our Design Tokens in their generated formats, we can be sure to not end up with 261 shades of blue.

Maintainability

By using a pre-processor like Sass, or using native CSS custom properties, we can already have maintainable code in our projects. Design Tokens also do this at the abstracted level as well.

Scalability

“Design Tokens enable us to scale our Design across all the permutations.”
– Jina

At this point, we’re only talking about abstracting the design decisions for use in CSS. Having Design Tokens allows design to scale for multiple brands or multiple projects as needed.

The main benefit of Design Tokens in regards to scalability is the option that it gives us to offer the Design Tokens for other platforms and frameworks as needed. With some of the tools available, we can even have these Tokens shared between applications used by designers and developers.

Your marketing site and your iOS application can soon share the same design decisions codified, and you can move towards creating an Android app or web application as required.

Documentation

If we abstract the design decisions from one platform specific programming language it would be no good if it wasn’t made to be easily accessible.

The tools and applications available that are mentioned later in this article can now create their own documentation, or allow you to create your own. This documentation is either hosted within a web-based application or can be self-hosted with the rest of your Design Systems documentation.

Most of the command line tools go further and allow you do add more details that you wish to convey in the documentation, making it as unique as it is required for your project.

Empowerment

When you abstract your design decisions to Design Tokens, you can help empower other people on the project. With the tools available today, and the tools that are just around the corner, we can have these design decisions determined by anyone on the team.

No-one necessarily needs to understand how to set up the codebase to update the colour slightly. Some of the tools I mention later on allow you to update the Design Tokens in the browser.

Design Systems are already “bridging the gap” between design and development. With Design Tokens and the tooling available, we can create better team relationships by closing that gap instead.

Some of the benefits of creating and using Design Tokens are the same as using a pre-processor when it comes to authoring CSS. I feel the added bonuses of being able to empower other team members and document how you use them, as well as the fundamental reasoning in that they can be platform agnostic, are all great “selling points” to why you need to start using Design Tokens today.

Tools

There are several tools available to help you and your team to create the required files from your abstracted Design Tokens:

Command Line Tools

There are several tools available on the command line that can be used as part of, or separate to, your development process.

These tools allow you to define the Design Tokens in a .json or .yaml file format which can then be compiled into the formats you require.

Some have built in functions to turn the inputted values to something different when compiled – for example, turning hexadecimal code that is a Design Token into a RGB value in your .css file. These command line tools, written in JavaScript, allow you to create your own ways in which you want things transformed.

My current client has certain design decisions for typography in long form content (font size, weight, line height and margins) which need to be together to make sense. Being able to write JavaScript to compile these design decisions into an independent Sass map for each element allows us to develop with assurance that the long form content has the correct styling.

WYSIWYG Tools

WYSIWYG (What You See Is What You Get Tools) have been around for almost as long as we have been able to make websites. I can just about remember using Dreamweaver 2, before I knew what a <table> was.

When browsers started to employ vendor prefixes to new CSS for their browsers, a flurry of online WYSIWYG tools came with it built in. They’re still there, but the industry has moved on.

Design Tokens also have a few WYSIWYG tools available. From simpler online tools that allow you to generate the correct Sass variables needed for your design decisions to tools that store your decisions online and allow you to export them as npm packages.

These types of tools for creating Design Tokens can help empower the team as a whole, with some automatically creating documentation which can easily be shared with a url.

Retrofitting Tools

If you are starting from scratch on a new re-design or on a new project that requires a Design System and Tokens, the many of the tools mentioned above will help you along your way. But what if you’re in the middle of a project, or you have to maintain something and want to start to create the parts required for a Design System?

Luckily there are several tools and techniques to help you make a start.

One new tool that might be useful is Superposition. Currently in private beta with the public release set for Q1 of 2020 Superposition helps you “Extract design tokens from websites and use them in code and in your design tool.”

Entering your domain gives you a nice visual documentation of your sites styles as Design Tokens. These can then be exported as Sass Variables, CSS Custom Properties, JavaScript with the team working on exports to iOS and Android.

If you have an existing site, this could be a good first step before moving to one of the other tools mentioned above.

You could also make use of CSSStats or Project Wallace’s Analysis page that I mentioned earlier. This would give you an indication of what Design Tokens you would need to implement.

Component Based Design

So, we’ve created our Design Tokens by abstracting the design decisions of brand colours, typography, spacing and more. Is that as far as we can go?

Levels of Design Decisions

Once we have created our first set of Design Tokens for our project, we can take it that little bit deeper. With command line tools and some of the applications available, you can link these more global decisions to a more deeper level.

For example, you can take your chosen colours and make further design decisions on the themes of your project, such as what the primary, secondary, or tertiary colours are or what your general component and layout spacing will be.

With this, we can go one step further. We could also define some component specific design decisions that can then be compiled for the developer to use. Invest in time to check over the designs with a fine toothcomb and make sure you are using the correct Sass variable or CSS custom property for that component.

If you are going more than one or two levels of design decision making, you can compile each set of these Design Tokens to your Sass variables which can then be used as required. So you can provide: global, theme, component level Sass variables which can be used in the project. Or you could choose to only compile what you need for the components you are creating.

Variables, Maps, Custom Properties

Some of the tools available for creating and maintaining your Design Tokens allow you to compile to certain programming languages.

With my current client work, I am making use of Sass variables, Sass maps, and CSS custom properties. The Design Tokens are compiled into one or more of these options depending on how they will be used.

Colours are compiled as global Sass variables, inside of a couple of Sass maps and CSS custom properties. Our macro layout breakpoints are defined as a single Sass map.

If we know we are creating a component that has the ability to be themed, we can make use of CSS custom properties to reduce the amount of CSS we need to override, and also allow us to inline things that can be changed via a CMS as required. Which leaves us using Sass variables for parts of a component that won’t change. We are using Sass maps differently still. As mentioned, we generate a Sass map containing the design decisions for each element of text, and we can use long form text. This Sass map is then compiled into separate CSS declarations as needed using Sass mixins.

I find the beauty of being able to make use of the global, themed, and component level design decisions by compiling them into various formats (that essentially become CSS) and that gives us more power in authoring components.

Creating Consistent Utility Classes

As you have created your more global generic design decisions, you can create your own small set of utility classes.

Using a pre-processor like Sass you can define a set of mixins and functions that can take your Design Tokens that have been compiled down into variables and maps and generate separate classes for each design decision.

By making tokens available to all digital teams, we can enable them to create custom experiences that are aligned to current visual standards when a component does not (or will not) exist in the design system. Maya King

In creating utility classes with Design Tokens (using something like Sass) you have consistency with the overall Design System for times when you or a team need to create a one-off component for a project.

These exceptions tend to be something that won’t make it as part of the overall Design System, but it still needs that look and feel.

Having classes available that we can guarantee use the generic, global design decisions from the Design Tokens means these one-off components should be well on their way to have the overall look and feel of the project, and will get any updates with little to no additional overhead.

Wrapping Up

I think we are starting to see the potential of using Design Tokens as Design Systems become even more popular. I think that, from this overview, we can see how they can help us close the gap that still exists in places between the designers and developers on the team. They can help empower people who do not code to make changes that can be automatically updating live work.

I think you can start now. You may not have or need what you could term “a fully-fledged Design System” but this small step will help move towards one in the future and give you instant benefits of consistency and maintainability now. If you want more Design Tokens, as well as the links that are dotted around this article I also maintain a GitHub repo of Awesome Design Tokens which I try to keep updated with links to tools, articles, examples, videos, and anything else that’s related to Design Tokens.

About the author

Stuart Robson is a freelance front-end developer and design systems advocate who curates the design systems newsletter - news.design.systems