Bootstrap/site/docs/4.3/utilities/embed.md

layout	title	description	group	toc
docs	Embeds	Create responsive video or slideshow embeds based on the width of the parent by creating an intrinsic ratio that scales on any device.	utilities	true

About

Rules are directly applied to <iframe>, <embed>, <video>, and <object> elements; optionally use an explicit descendant class .embed-responsive-item when you want to match the styling for other attributes.

Pro-Tip! You don't need to include frameborder="0" in your <iframe>s as we override that for you.

Example

Wrap any embed like an <iframe> in a parent element with .embed-responsive and an aspect ratio. The .embed-responsive-item isn't strictly required, but we encourage it.

{% capture example %}

{% endcapture %} {% include example.html content=example %}

Aspect ratios

Aspect ratios can be customized with modifier classes. By default the following ratio classes are provided:

{% highlight html %}

{% endhighlight %}

Within _variables.scss, you can change the aspect ratios you want to use. Here's an example of the $embed-responsive-aspect-ratios list:

{% highlight scss %} $embed-responsive-aspect-ratios: ( (21 9), (16 9), (4 3), (1 1) ) !default; {% endhighlight %}