ui/docs/content/1.getting-started/5.theme.md

description

description
Learn how to customize the look and feel of the components.

This module relies on Nuxt App Config file to customize the look and feel of the components at runtime with HMR (hot-module-replacement).

Colors

Configuration

Components are based on a primary and a gray color. You can change them in your app.config.ts.

export default defineAppConfig({
  ui: {
    primary: 'green',
    gray: 'cool'
  }
})

::callout{icon="i-heroicons-light-bulb"} Try to change the primary and gray colors by clicking on the :u-icon{name="i-heroicons-swatch-20-solid" class="w-4 h-4 align-middle text-primary-500 dark:text-primary-400"} button in the header. ::

As this module uses Tailwind CSS under the hood, you can use any of the Tailwind CSS colors or your own custom colors. By default, the primary color is green and the gray color is cool.

When using custom colors or adding additional colors through the extend key in your tailwind.config.ts, you'll need to make sure to define all the shades from 50 to 950 as most of them are used in the components config defined in ui.config/ directory. You can generate your colors using tools such as https://uicolors.app/ for example.

import type { Config } from 'tailwindcss'
import defaultTheme from 'tailwindcss/defaultTheme'

export default <Partial<Config>>{
  theme: {
    extend: {
      colors: {
        green: {
          50: '#EFFDF5',
          100: '#D9FBE8',
          200: '#B3F5D1',
          300: '#75EDAE',
          400: '#00DC82',
          500: '#00C16A',
          600: '#00A155',
          700: '#007F45',
          800: '#016538',
          900: '#0A5331',
          950: '#052e16'
        }
      }
    }
  }
}

CSS Variables

To provide dynamic colors that can be changed at runtime, this module uses CSS variables. As Tailwind CSS already has a gray color, the module automatically renames it to cool to avoid conflicts (coolGray was renamed to gray when Tailwind CSS v3.0 was released).

Likewise, you can't define a primary color in your tailwind.config.ts as it would conflict with the primary color defined by the module.

::callout{icon="i-heroicons-light-bulb"} We'd advise you to use those colors in your components and pages, e.g. text-primary-500 dark:text-primary-400, bg-gray-100 dark:bg-gray-900, etc. so your app automatically adapts when changing your app.config.ts. ::

The primary color also has a DEFAULT shade that changes based on the theme. It is 500 in light mode and 400 in dark mode. You can use as a shortcut in your components and pages, e.g. text-primary, bg-primary, focus-visible:ring-primary, etc.

Components

app.config.ts

You can find the config of each component in the ui.config/ directory. You can override those classes in your own app.config.ts.

export default defineAppConfig({
  ui: {
    container: {
      constrained: 'max-w-5xl'
    }
  }
})

Thanks to tailwind-merge, the app.config.ts is smartly merged with the default config. This means you don't have to rewrite everything.

You can change this behavior by setting strategy to override in your app.config.ts:

export default defineAppConfig({
  ui: {
    strategy: 'override',
    button: {
      color: {
        white: {
          solid: 'bg-white dark:bg-gray-900'
        }
      }
    }
  }
})

ui prop

Each component has a ui prop that allows you to customize everything specifically.

<template>
  <UContainer :ui="{ constrained: 'max-w-2xl' }">
    <slot />
  </UContainer>
</template>

::callout{icon="i-heroicons-light-bulb"} You can find the default classes for each component under the Config section. ::

Thanks to tailwind-merge, the ui prop is smartly merged with the config. This means you don't have to rewrite everything.

For example, the default preset of the FormGroup component looks like this:

{
  "label": {
    "base": "block font-medium text-gray-700 dark:text-gray-200"
  }
}

To change the font of the label, you only need to write:

<UFormGroup name="email" label="Email" :ui="{ label: { base: 'font-semibold' } }" />

This will smartly replace the font-medium by font-semibold and prevent any class duplication and any class priority issue.

You can change this behavior by setting strategy to override inside the ui prop:

<UButton
  to="https://github.com/nuxt/ui"
  :ui="{
    strategy: 'override',
    color: {
      white: {
        solid: 'bg-white dark:bg-gray-900'
      }
    }
  }"
/>

class attribute

You can also use the class attribute to add classes to the component.

<template>
  <UButton label="Button" class="rounded-full" />
</template>

Again, with tailwind-merge, this will smartly merge the classes with the ui prop and the config.

Default values

Some component props like size, color, variant, etc. have a default value that you can override in your app.config.ts.

export default defineAppConfig({
  ui: {
    button: {
      default: {
        size: 'md',
        color: 'gray',
        variant: 'ghost'
      }
    }
  }
})

Dark mode

All the components are styled with dark mode in mind.

Thanks to Tailwind CSS dark mode class strategy and the @nuxtjs/color-mode module, you literally have nothing to do.

You can disable dark mode by setting the preference to light instead of system in your nuxt.config.ts.

export default defineNuxtConfig({
  colorMode: {
    preference: 'light'
  }
})

::callout{icon="i-heroicons-light-bulb"} If you're stuck in dark mode even after changing this setting, you might need to remove the nuxt-color-mode entry from your browser's local storage. ::