The library is composed of dozens of utility classes written in raw CSS (not a preprocessor such as Sass or Less). Unlike Atomic CSS, util.css does not contain (with a few exceptions) single-purpose units of styles, such as .text-center {text-align: center}. Instead, it focuses on common helpers and fixes that add functionality beyond simple shortcuts. Theses classes are unopinionated and modular declarations, making them applicable to and easily adopted into any project.
The following is a complete list of all the classes available, grouped into categories. Note: For class names, the word "center" refers to horizontal alignment and the word "middle" refers to vertical alignment.
Layout
Class
Description
clearfix
Allows an element to stretch to accommodate floating elements
border-box
Make the box model of an element and its descendants include the padding and border within the defined width and height of an element
content-box
Make the box model of an element and its descendants add the padding and border to the defined width and height of an element
responsive-width
Sets a maximum width relative to the parent and auto scales the height
responsive-height
Sets a maximum height relative to the parent and auto scales the width (parent element must have a fixed height)
flex-middle-center
Should align children in the middle-center of the element using flexbox
grid-middle-center
Should align children in the middle-center of the element using grid
flex-inline-middle-center
Should align children in the middle-center of the element using inline flexbox
flex-horizontal-stack
Should stack children horizontally using flexbox
flex-vertical-stack
Should stack children vertically using flexbox
Visibility
Class
Description
hidden
Hide an element visually and from screen readers
invisible
Hide an element visually and from screen readers, but maintain layout
transparent
Hide an element visually, but still allow it to be accessible to screen readers, maintain layout, and allow pointer events
offscreen
Hide an element visually, but maintain its layout offscreen so that its width and height and still be accurately measured
hidden-accessible
Hide an element visually, but still allow it to be accessible to screen readers
hidden-accessible-focusable
Like hidden-accessible, but will be visible when it or a child element receives focus
hidden-scrollbars
Hide scrollbars on an element, while still allowing it to be scrollable
hidden-touch
Make an element hidden on touch devices
hidden-non-touch
Make an element hidden on non-touch devices
Alignment
Class
Description
align-left
Float an element left
align-right
Float an element right
align-center
Center an element horizontally
align-middle
Center an element vertically
align-middle-center
Center an element horizontally and vertically
align-abs-top-left
Align an absolutely positioned element to the top-left of its container
align-abs-top-center
Align an absolutely positioned element to the top-center of its container
align-abs-top-right
Align an absolutely positioned element to the top-right of its container
align-abs-middle-left
Align an absolutely positioned element to the middle-left of its container
align-abs-middle-center
Align an absolutely positioned element to the middle-center of its container
align-abs-middle-right
Align an absolutely positioned element to the middle-right of its container
align-abs-bottom-left
Align an absolutely positioned element to the bottom-left of its container
align-abs-bottom-center
Align an absolutely positioned element to the bottom-center of its container
align-abs-bottom-right
Align an absolutely positioned element to the bottom-right of its container
align-self-top-left
Align an element to the top-left within a flexbox or grid container
align-self-top-center
Align an element to the top-center within a flexbox or grid container
align-self-top-right
Align an element to the top-right within a flexbox or grid container
align-self-middle-left
Align an element to the middle-left within a flexbox or grid container
align-self-middle-center
Align an element to the middle-center within a flexbox or grid container
align-self-middle-right
Align an element to the middle-right within a flexbox or grid container
align-self-bottom-left
Align an element to the bottom-left within a flexbox or grid container
align-self-bottom-center
Align an element to the bottom-center within a flexbox or grid container
align-self-bottom-right
Align an element to the bottom-right within a flexbox or grid container
Typography
Class
Description
antialiased
Render text using grayscale antialiasing
subpixel-antialiased
Render text using subpixel antialiasing
text-truncate
Prevent text from wrapping and truncate with an ellipsis
text-clip
Prevent text from wrapping and truncate with a hard clip
text-break
Break words when their length exceeds the width of their container
Media
Class
Description
hide-text
Image replacement to provide a caption to an image that is only available to web crawlers and screen readers
image-responsive
Make an image responsive while maintaining aspect ratio
image-contain
Fit the image within the container while preserving its aspect ratio
image-cover
Fill the container with the image while preserving its aspect ratio
User Experience
Class
Description
unselectable
Prevent text selection
disabled
Prevent user interaction of any kind
scroll-horizontal
Make an element display only horizontal scrollbars
scroll-vertical
Make an element display only vertical scrollbars
License
This project is dedicated to the public domain as described by the Unlicense.