Conditional Classes

Stacks provides conditional atomic classes to easily build complex responsive designs, hover states, and print layouts.


Many utility classes in Stacks are also available in screen-size specific variations. For example, the .d-none utility can be applied to small browser widths and below using the .sm:d-none class, on medium browser widths and below using the .md:d-none class, and on large browser widths and below using the .lg:d-none class.

This is done using predefined max-width media query breakpoints represented by t-shirt sizes. A common example would be to apply .md:fd-column to a grid. This means, “At the medium breakpoint and smaller, switch the grid from columns to rows by applying fd-column.”

Note: Our font size classes, .fs-[x] are automatically adjusted at the smallest breakpoint.

Responsive Classes

Breakpoint Classname Definition
All / Default .[x] The class is applied on all browser widths.
Large .lg:[x] The class is applied on large browser widths and below.
Medium .md:[x] The class is applied on medium browser widths and below.
Small .sm:[x] The class is applied on small browser widths and below.

Responsive Example

Resize your browser to see which classes are applied.

<div class="grid ai-center md:fd-column gs16">
    <div class="grid--cell fs-body3 lg:ta-center"></div>
    <div class="grid--cell sm:d-none">
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Stacks provides hover-only atomic classes. By applying .h:bs-lg, .h:o100, and .h:fc-black-900, you’re saying “On hover, add a large box shadow, an opacity of 100%, and a font color of black 900.”

<div class="s-card h80 bs-sm h:bs-lg h:o100 h:fc-black-900"></div>


Stacks provides print-only atomic classes. By applying .print:d-none, you’re saying “In print layouts, remove this element from the layout.”

<div class="s-card print:d-none"></div>
This element will be removed from the page while printing.


A limited selection of conditional classes are available throughout Stacks. These are represented in class definitions tables by .