Ratios
Use generated pseudo elements to make an element maintain the aspect ratio of your choosing. Perfect for responsively handling video or slideshow embeds based on the width of the parent.
About
Use the ratio helper to manage the aspect ratios of external content like
<iframe>s, <embed>s, <video>s, and
<object>s. These helpers also can be used on any standard HTML child element (e.g.,
a <div> or <img>). Styles are applied from the parent
.ratio class directly to the child.
Aspect ratios are declared in a Sass map and included in each class via CSS variable, which also allows custom aspect ratios.
Pro-Tip! You don’t need frameborder="0" on your
<iframe>s as we override that for you in
Reboot.
Example
Wrap any embed, like an <iframe>, in a parent element with .ratio and
an aspect ratio class. The immediate child element is automatically sized thanks to our universal
selector .ratio > *.
Aspect ratios
Aspect ratios can be customized with modifier classes. By default the following ratio classes are provided: