---
layout: page
title: Media queries
---

Since Bootstrap is designed to be mobile-first, we employ media queries in our CSS to create responsive pages and components. Media queries allow you to group rulesets by a handful of parameters, most notably viewport dimensions, to gracefully scale content across devices.

### Common queries

Bootstrap mainly uses the following media query ranges in our source Sass files for key breakpoints in our layout, grid system, and components.

{% highlight scss %}
/* Extra small devices (portrait phones, less than ???px) */
/* No media query since this is the default in Bootstrap */

/* Small devices (landscape phones, 34em and up) */
@media (min-width: 34em) { ... }

/* Medium devices (tablets, 48em and up) */
@media (min-width: 48em) { ... }

/* Large devices (desktops, 62em and up) */
@media (min-width: 62em) { ... }

/* Extra large devices (large desktops, 75em and up) */
@media (min-width: 75em) { ... }
{% endhighlight %}

These media queries are available via Sass mixins:
{% highlight scss %}
@include media-breakpoint-up(xs) { ... }
@include media-breakpoint-up(sm) { ... }
@include media-breakpoint-up(md) { ... }
@include media-breakpoint-up(lg) { ... }
@include media-breakpoint-up(xl) { ... }

// Example usage:
@include media-breakpoint-up(sm) {
  .some-class {
    display: block;
  }
}
{% endhighlight %}

We occasionally use media queries that go in the other direction (the given screen size *or smaller*):
{% highlight scss %}
/* Extra small devices (portrait phones, less than 34em) */
@media (max-width: 33.9em) { ... }

/* Small devices (landscape phones, less than 48em) */
@media (max-width: 47.9em) { ... }

/* Medium devices (tablets, less than 62em) */
@media (max-width: 61.9em) { ... }

/* Large devices (desktops, less than 75em) */
@media (max-width: 74.9em) { ... }

/* Extra large devices (large desktops) */
/* No media query since the extra-large breakpoint has no upper bound on its width */
{% endhighlight %}

These media queries are available via Sass mixins:
{% highlight scss %}
@include media-breakpoint-down(xs) { ... }
@include media-breakpoint-down(sm) { ... }
@include media-breakpoint-down(md) { ... }
@include media-breakpoint-down(lg) { ... }
@include media-breakpoint-down(xl) { ... }
{% endhighlight %}