Twitter Bootstrap: Add Media Queries for Xxs Breakpoint

Twitter Bootstrap 3: how to use media queries?

Bootstrap 3

Here are the selectors used in BS3, if you want to stay consistent:

@media(max-width:767px){}
@media(min-width:768px){}
@media(min-width:992px){}
@media(min-width:1200px){}

Note: FYI, this may be useful for debugging:

<span class="visible-xs">SIZE XS</span>
<span class="visible-sm">SIZE SM</span>
<span class="visible-md">SIZE MD</span>
<span class="visible-lg">SIZE LG</span>

Bootstrap 4

Here are the selectors used in BS4. There is no "lowest" setting in BS4 because "extra small" is the default. I.e. you would first code the XS size and then have these media overrides afterwards.

@media(min-width:576px){}
@media(min-width:768px){}
@media(min-width:992px){}
@media(min-width:1200px){}

Bootstrap 5

@media(min-width:576px){}
@media(min-width:768px){}
@media(min-width:992px){}
@media(min-width:1200px){}
@media(min-width:1400px){}

Update 2021-05-20: Info is still accurate as of versions 3.4.1, 4.6.0, 5.0.0.

Twitter Bootstrap - how to detect when media queries starts

Using jquery you can find the size of current window and then accordingly do your stuff.

$(window).resize(function() {
  if ($(this).width() >= 1280) {
    //do something
  }
  else if ($(this).width() < 1280 && $(this).width()>= 980) {
    //do something
  }
  ...
});

CSS:: Twitter-Bootsrap-layouts

/* Large desktop */
@media (min-width: 1200px) { ... }

/* Portrait tablet to landscape and desktop */
@media (min-width: 768px) and (max-width: 979px) { ... }

/* Landscape phone to portrait tablet */
@media (max-width: 767px) { ... }

/* Landscape phones and down */
@media (max-width: 480px) { ... }

Twitter bootstrap media queries breakpoints

According to Bootstrap, extra small devices are for less than 768px (up to 767px), and small devices are greater than or equal to 768px. These values seem to be exactly where they need to be and I would use them. Check out this list of displays by pixel density and I think you'll see most devices fall within the pixel width of their respective Bootstrap group.

How to create new breakpoints in bootstrap 4 using CDN?

I'm very surprised that there was no developer able to answer my question! Even on the github no one dared to think about it!

In fact, everything turned out to be very simple!

Yes, using the CDN we get the compiled css file. Styles in the bootstrap are written using sass. Moreover, the styles are written separation and modular. So it means that I do not need to load the entire bootstrap to my server. I want to deliver cached version of Bootstrap’s compiled CSS and I only need to add my breakpoints. Fortunately, there is a specific bootstrap file which is responsible for the Grid. It is bootstrap-grid.scss:

/*!
 * Bootstrap Grid v4.0.0 (https://getbootstrap.com)
 * Copyright 2011-2018 The Bootstrap Authors
 * Copyright 2011-2018 Twitter, Inc.
 * Licensed under MIT (https://github.com/twbs/bootstrap/blob/master/LICENSE)
 */

@at-root {
  @-ms-viewport { width: device-width; } // stylelint-disable-line at-rule-no-vendor-prefix
}

html {
  box-sizing: border-box;
  -ms-overflow-style: scrollbar;
}

*,
*::before,
*::after {
  box-sizing: inherit;
}

@import "functions";
@import "variables";

@import "mixins/breakpoints";
@import "mixins/grid-framework";
@import "mixins/grid";

@import "grid";
@import "utilities/display";
@import "utilities/flex";

Now I just need to add sequentially the code from the files above adding my breakpoints. Add non-Grid code not necessary. For example, the code responsible for the color. Here is my mcve at codepen.

Using media breakpoints in Bootstrap 4-alpha

Update: Bootstrap 5.

v5 breakpoints reference

Original answer - Bootstrap v4: Use breakpoint mixins like this:

.something {
    padding: 5px;
    @include media-breakpoint-up(sm) { 
        padding: 20px;
    }
    @include media-breakpoint-up(md) { 
        padding: 40px;
    }
}

v4 breakpoints reference

v4 alpha6 breakpoints reference

Below full options and values.

Breakpoint & up (toggle on value and above):

@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) { ... }

breakpoint & up values:

// Extra small devices (portrait phones, less than 576px)
// No media query since this is the default in Bootstrap

// Small devices (landscape phones, 576px and up)
@media (min-width: 576px) { ... }

// Medium devices (tablets, 768px and up)
@media (min-width: 768px) { ... }

// Large devices (desktops, 992px and up)
@media (min-width: 992px) { ... }

// Extra large devices (large desktops, 1200px and up)
@media (min-width: 1200px) { ... }

breakpoint & down (toggle on value and down):

@include media-breakpoint-down(xs) { ... }
@include media-breakpoint-down(sm) { ... }
@include media-breakpoint-down(md) { ... }
@include media-breakpoint-down(lg) { ... }

breakpoint & down values:

// Extra small devices (portrait phones, less than 576px)
@media (max-width: 575px) { ... }

// Small devices (landscape phones, less than 768px)
@media (max-width: 767px) { ... }

// Medium devices (tablets, less than 992px)
@media (max-width: 991px) { ... }

// Large devices (desktops, less than 1200px)
@media (max-width: 1199px) { ... }

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

breakpoint only:

@include media-breakpoint-only(xs) { ... }
@include media-breakpoint-only(sm) { ... }
@include media-breakpoint-only(md) { ... }
@include media-breakpoint-only(lg) { ... }
@include media-breakpoint-only(xl) { ... }

breakpoint only values (toggle in between values only):

// Extra small devices (portrait phones, less than 576px)
@media (max-width: 575px) { ... }

// Small devices (landscape phones, 576px and up)
@media (min-width: 576px) and (max-width: 767px) { ... }

// Medium devices (tablets, 768px and up)
@media (min-width: 768px) and (max-width: 991px) { ... }

// Large devices (desktops, 992px and up)
@media (min-width: 992px) and (max-width: 1199px) { ... }

// Extra large devices (large desktops, 1200px and up)
@media (min-width: 1200px) { ... }

In which ordering to use Twitter Bootstrap Breakpoints?

CSS cascade rules apply to media queries so, if you want to override a rule with a media query, you need to make sure that the media query contains a rule with the identical selectors (or selectors with more specificity) and that it is loaded after the rule you want to override.

Same applies when you have multiple media queries. The cascade order along with rules for specificity and inheritance will dictate whether the media query is applied. Take for example:

body {
    background-color: teal;
}
@media (min-width: 600px) {
    body {
        background-color: tomato;
    }
}
@media (min-width: 400px) {
    body {
        background-color: yellowgreen;
    }
}

Each of the selectors above are identical so they have the same specificity, but because of the cascade order, the background will never be the tomato color. If the body is 600 or more pixel wide, the rule for making the background tomato will be overridden by the last rule which also applies because 600px is also wider than 400px.

If you reorder the rules as follows:

body {
    background-color: teal;
}
@media (min-width: 400px) {
    body {
        background-color: yellowgreen;
    }
}
@media (min-width: 600px) {
    body {
        background-color: tomato;
    }
}

Now, the body background will be teal, when the body is less than 400px wide. It will be yellowgreen when the body is 400px - 599px and it will be tomato, when the background is 600px wide or greater.

Of course, you can use max-width too. For example, if you had the following order, the limit on the width at 599px for the yellowgreen rule would ensure that that rule didn't apply once the body was 600px or more:

body {
    background-color: teal;
}
@media (min-width: 600px) {
    body {
        background-color: tomato;
    }
}
@media (min-width: 400px) and (max-width: 599px) {
    body {
        background-color: yellowgreen;
    }
}

So, for the TL;DR version, think mobile first. Organize your stylesheets with your base styles define for your smallest devices. Then order your media queries from the next smallest device sizes and up such that the largest devices you want to support are last.

And, don't forget to make sure that the rules in your media queries use selectors are identical to or have more specificity than the rule you want to override.