1. Sizing
  2. block-size

Sizing

block-size

Utilities for setting the block size of an element.

ClassStyles
block-<number>
block-size: calc(var(--spacing) * <number>);
block-<fraction>
block-size: calc(<fraction> * 100%);
block-auto
block-size: auto;
block-px
block-size: 1px;
block-full
block-size: 100%;
block-screen
block-size: 100vh;
block-dvh
block-size: 100dvh;
block-dvw
block-size: 100dvw;
block-lvh
block-size: 100lvh;
block-lvw
block-size: 100lvw;

Examples

Basic example

Use block-<number> utilities like block-24 and block-64 to set an element to a fixed block size based on the spacing scale:

block-96
block-80
block-64
block-48
block-40
block-32
block-24
<div class="block-96 ...">block-96</div><div class="block-80 ...">block-80</div><div class="block-64 ...">block-64</div><div class="block-48 ...">block-48</div><div class="block-40 ...">block-40</div><div class="block-32 ...">block-32</div><div class="block-24 ...">block-24</div>

Using a percentage

Use block-full or block-<fraction> utilities like block-1/2 and block-2/5 to give an element a percentage-based block size:

block-full
block-9/10
block-3/4
block-1/2
block-1/3
<div class="block-full ...">block-full</div><div class="block-9/10 ...">block-9/10</div><div class="block-3/4 ...">block-3/4</div><div class="block-1/2 ...">block-1/2</div><div class="block-1/3 ...">block-1/3</div>

Matching viewport

Use the block-screen utility to make an element span the entire block size of the viewport:

<div class="block-screen">  <!-- ... --></div>

Matching dynamic viewport

Use the block-dvh utility to make an element span the entire block size of the viewport, which changes as the browser UI expands or contracts:

<div class="block-dvh">  <!-- ... --></div>

Matching large viewport

Use the block-lvh utility to set an element's block size to the largest possible size of the viewport:

<div class="block-lvh">  <!-- ... --></div>

Matching small viewport

Use the block-svh utility to set an element's block size to the smallest possible size of the viewport:

<div class="block-svh">  <!-- ... --></div>

Using a custom value

Use the block-[<value>] syntax to set the block size based on a completely custom value:

<div class="block-[32rem] ...">  <!-- ... --></div>

For CSS variables, you can also use the block-(<custom-property>) syntax:

<div class="block-(--my-block-size) ...">  <!-- ... --></div>

This is just a shorthand for block-[var(<custom-property>)] that adds the var() function for you automatically.

Responsive design

Prefix a block-size utility with a breakpoint variant like md: to only apply the utility at medium screen sizes and above:

<div class="block-1/2 md:block-full ...">  <!-- ... --></div>

Learn more about using variants in the variants documentation.

Customizing your theme

The block-<number> utilities are driven by the --spacing theme variable, which can be customized in your own theme:

@theme {  --spacing: 1px; }

Learn more about customizing the spacing scale in the theme variable documentation.

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