pcln-design-system

Priceline Design System

https://pricelinelabs.github.io/design-system/

npm i pcln-design-system

Motivation

In order to create a consistently great experience for our users, the design system is meant to be the single source of truth for user interface standards for both designers and developers.

Built off of the work of previous efforts, this project intends to consolidate those ideas into a living, well-documented, and growing system.

Goals

The core goals of this project are to:

• Speed up design and development velocity
• Help create consistent, beautiful, and usable UI in our applications
• Promote best practices for accessibility, internationalization, and responsive web design

We hope to accomplish these goals by:

• Reducing the number of decisions needed when iterating on UI
• Reducing the amount of code duplication in our apps
• Serving as the standard for Priceline.com's visual language
• Providing easy-to-use and extensible components for anyone to consume

ThemeProvider

To use the design system in a React app, wrap the root component with the ThemeProvider. This will set typographic defaults and pass the theme as context, which allows styled-components to consume the theme.

import { ThemeProvider } from 'pcln-design-system'

const App = props => (
  <ThemeProvider>
    <h1>Hello</h1>
  </ThemeProvider>
)

// Usage with styled-components
import styled from 'styled-components'

const Section = styled.section`
  background-color: ${props => props.theme.blue};
`

Primitive UI Components

The preferred way of using the design system in a React application is with UI primitives. With effective use of the UI primitives, you can reduce the need to write custom CSS in your application.

import React from 'react'
import { ThemeProvider, Box, Text } from 'pcln-design-system'

const App = props => (
  <ThemeProvider>
    <Box p={3}>
      <Text>Hello</Text>
    </Box>
  </ThemeProvider>
)

<Text />

Use the <Text /> component to control font size, weight, alignment, and color.

// Font size 4 on the typographic scale
<Text fontSize={4} />

// Center aligned
<Text align='center' />

// Bold weight
<Text bold />

// All-caps
<Text caps />

// Blue text from the color palette
<Text color='blue' />

Prop	Type	Description
fontSize	number or string	Sets font size based on the typographic scale
align	string	Sets the text-align property
bold	boolean	Sets font-weight: props.theme.bold
caps	boolean	Sets styles for all-caps type treatments
color	string	Sets color based on the theme's color palette
m	number, string, or array	Sets margin based on the theme.space scale
mt	number, string, or array	Sets margin-top
mr	number, string, or array	Sets margin-right
mb	number, string, or array	Sets margin-bottom
ml	number, string, or array	Sets margin-left
mx	number, string, or array	Sets margin-left and margin-right
my	number, string, or array	Sets margin-top and margin-bottom

By default, the <Text /> component renders a <div> element. To use a <span> or <p> element, use the following:

<Text.span>This is a span element</Text.span>
<Text.p>This is a p element</Text.p>

<Box />

Use the <Box /> component to control width, margin, padding, and color.

// 50% width
<Box width={1/2} />

// Padding of `theme.space[3]` (16px)
<Box p={3} />

// Margin of `theme.space[2]` (8px)
<Box m={2} />

// Color blue from the theme's color palette
<Box color='blue' />

// Background color green from the theme's color palette
<Box bg='green' />

Prop	Type	Description
width	number, string, or array	Sets the width of the element
color	string	Sets color based on the theme's color palette
bg	string	Sets background-color based on the theme's color palette
m	number, string, or array	Sets margin based on the theme.space scale
mt	number, string, or array	Sets margin-top
mr	number, string, or array	Sets margin-right
mb	number, string, or array	Sets margin-bottom
ml	number, string, or array	Sets margin-left
mx	number, string, or array	Sets margin-left and margin-right
my	number, string, or array	Sets margin-top and margin-bottom
p	number, string, or array	Sets padding based on the theme.space scale
pt	number, string, or array	Sets padding-top
pr	number, string, or array	Sets padding-right
pb	number, string, or array	Sets padding-bottom
pl	number, string, or array	Sets padding-left
px	number, string, or array	Sets padding-left and padding-right
py	number, string, or array	Sets padding-top and padding-bottom

Responsive Widths

The width prop accepts an array value to set different widths at different breakpoints with a mobile-first approach.

<Box
  width={[
    1,    // Sets width 100% at the smallest breakpoint
    1/2,  // Sets width 50% at the next breakpoint
    1/4,  // Sets width 25% at the next breakpoint
  ]}
/>

<Flex />

The <Flex /> component is an extension of the <Box /> component with display: flex and props for using flexbox.

<Flex>
  <Box width={1/2}>Flex</Box>
  <Box width={1/2}>Box</Box>
</Flex>

Prop	Type	Description
align	string	sets align-items
justify	string	sets justify-content
wrap	boolean	sets flex-wrap: wrap

<Image />

Use the <Image /> component to render a primitive image that saves the aspect ratio.

<Image src='https://priceline.com/myimage.png' />

// Adding fixed width
<Image src='https://priceline.com/myimage.png' width='300' height='200' alt='My Image'/>

<Icon />

Use the <Icon /> component for SVG icons.

<Icon
  name='circlePlus'
  size={48}
  color='blue'
/>

Prop	Type	Description
name	string	icon key name
size	number	width and height in pixels
color	string	a color key from theme.colors

Theme

The theme style constants should be used whenever low-level access to font sizes, margin, padding, media queries, and colors are needed.

import {
  theme,
} from 'pcln-design-system'

// or
import {
  colors,
  mediaQueries,
  fontSizes,
  space
} from 'pcln-design-system'

Colors

import { colors } from 'pcln-design-system'

colors.blue // '#0a84c1'

Font Sizes

import { fontSizes } from 'pcln-design-system'

fontSizes[2] // 16

The theme includes a typographic scale as the fontSizes array. Use these values whenever declaring a font-size in CSS.

Spacing Scale

The space array should be used whenever declaring margin or padding values.

import { space } from 'pcln-design-system'

space[0] // 0
space[1] // 4
space[2] // 8
space[3] // 16
space[4] // 32
space[5] // 64
space[6] // 128

MIT License