The most important part of responsive web design is that, no matter what the viewport width, the content is accessible in an optimum display. The best responsive designs are those that allow you to go from one optimised display to another, but with the feeling that these experiences are part of a greater product whole.

Responsive design: where we’ve been going wrong

Responsive web design was a shock to my web designer system. Those of us who had already been designing sites for mobile probably had the biggest leap to make. We might have been detecting user agents in order to deliver a mobile-specific site, or using the slightly more familiar Bushido technique to deliver sites optimised for device type and viewport size, but either way our focus was on devices. A site was optimised for either a mobile phone or a desktop.

Responsive web design brought us back to pre-table layout fluid sites that expanded or contracted to fit the viewport. This was a big difference to get our heads around when we were so used to designing for fixed-width layouts. Suddenly, an element could be any width or, at least, we needed to consider its maximum and minimum widths. Pixel perfection, while pretty, became wholly unrealistic, and a whole load of designers who prided themselves in detailed and precise designs got a bit scared.

Hanging on to our previous processes and typical deliverables led us to continue to optimise our sites for particular devices and provide pixel-perfect mockups for those device widths.

With all this we were concentrating on devices, not content, deliverables and not process, and making assumptions about users and their devices based on nothing but the width of the viewport.

I don’t think this is a crime, I think it was inevitable.

We can be up to date with our principles and ideals, but it’s never as easy in practice. That’s why it’s more important than ever to share our successful techniques and processes. Let’s drag each other into modern web design.

Design systems: the principles

What are design systems?

A visual design system is built out of the core components of typography, layout, shape or form, and colour. When considering the design of a whole product, a design system should also include patterns in user flow, content strategy, copy, and tone of voice. These concepts, design decisions or rules, created around the core components are used consistently across your product to create a cohesive feel, whether it’s from one element to another, page to page, or viewport width to viewport width.

Responsive design is one of the most important considerations in the components of a design system. For each component, you must decide what will unite the design across the viewports to maintain that consistent feel, and what parts of the design will differentiate in order to provide a flexible and optimal experience for different viewport sizes.

Components you might keep the same across viewports

  • typeface
  • base unit
  • colour
  • shape/form

Components you might differentiate across viewports

  • grids
  • layout
  • font size
  • measure (line length)
  • leading (line height)

Content: it must always be the same

The focus of a design system is the optimum display of content. As Mark Boulton put it, designing "content out, not canvas in." Chris Armstrong puts the emphasis on not designing for viewports but for content – "we need to build on what we do know: content." In order to do this, we must share the same content across all devices and focus on how best to display and represent content through design system components.

The practical: core visual components

Typography first

When you work with a lot of text content, typography is the easiest way to set the visual tone of the design across all viewport widths. It’s likely that you’ll choose one or two typefaces to use across the whole system, but you might change the most legible font size, balanced with the most comfortable measure, as the viewport width changes.

Where typography meets layout

The unit on which you choose to base the grid and layout design, font sizes and leading could be based on the typeface, an optimal reading size, or something more arbitrary. Sometimes I’ll choose a unit based on multiples of ten because it makes the maths in the easier. Tim Brown suggests trying a modular scale. Chris Armstrong suggests basing it on your ideal measure, or the width of a fixed item of content such as an ad unit.

Grids and layouts

Sensible grid design can be a flexible yet solid foundation for your design system layout component. But you must be wary in responsive design that a grid might not work across all widths: even four columns could make for very cramped content and one-word measures on smaller screens.

Maybe the grid columns are something you differentiate across widths, but you can keep the concept of the grid consistent. If the content has blocks in groups of three, you might decide on a three-column grid which folds down to one column for narrow viewports. If the grid focuses on the idea of symmetry and has a four-column grid on larger viewports, it might fold down to two columns for narrower viewports. These consistencies may seem subtle, not at all obvious to many except the designer, but it’s all these little constants and patterns across the whole of the design system that makes design decisions easier to make (as they adhere to the guiding concepts of your system), and give the product a uniform feel no matter what the device.

Shape or form

The shape or form components are concepts you already use in fixed-width web design for a strong, consistent look and feel.

Since border-radius became widely supported by browsers, a lot of designs feature circle themes. These are very distinctive and can be used across viewport widths giving them the same united feel, even if they’re not used in the same way. This could also apply to border styles, consistent shadows and any number of decorative details and textures. These are the elements that make up the shape or form of a design system.


Colour is the most basic way to reinforce a brand and unite experiences across viewports. The same hex colour used system-wide is instantly recognisable, no matter what the viewport width.

The process

While using a design system isn’t necessarily attached to any particular process, it does lend itself to some process ideals.

Detaching design considerations from viewport widths

A design system allows you to focus separately on the components that make up the system, disconnecting the look and feel from the layout. This helps prevent us getting stuck in the rut of the Apple breakpoints (brilliantly coined by Simon Foster) of mobile, tablet and desktop. It also forces us to design for variation in viewport experiences side by side, not one after the other.

Design in the browser

I can’t start off designing in the browser – it just doesn’t seem to bring out my creative side (and I’m incredibly envious of you if you can; I just have to start on paper) – but static mock-ups aren’t the only alternative. Style guides and style tiles are perfect for expressing the concepts of your design system. Pattern libraries could also work well.

Mock-ups and breakpoints

At some point, whether it’s to test your system ideas, or because a client needs help visualising how your system might work, you may end up producing some static mock-ups. It’s not the end of the world, but you must ensure that these consider all the viewports, not just those of the iDevices, or even the devices currently on the market. You need to decide the breakpoints where the states of your design change. The blocks within your content will always have optimum points for their display (based on their hierarchy, density, width, or type of interaction) and so your breakpoints should be based around these points.

These are probably the ideal points at which to produce static mockups; treat them as snapshots. They’re not necessarily mock-ups, so much as a way of capturing how your design system would be interpreted when frozen at that particular viewport width.

The future

Creating design systems will give us the flexibility we need for working with the unknown devices of the future. It may be a change in process, but it shouldn’t be too much of a difference in thinking. The pioneers in responsive design have a hard job. Some of these problems may have already been solved in other technologies or industries, but it’s up to the pioneers to find those connections and help us formulate solutions and standards that will make responsive design the best it can possibly be. We need to keep experimenting and communicating, particularly in the area of design, as good user experiences are the true sign of whether our products are a success.

Written by Laura Kalbag