Uploaded December 2019 | Updated September 2026, 2 weeks ago
Not sure where that default 8px of margin on the body comes from? Here's how to find out!
Every browser provides a User Agent (UA) Stylesheet to give HTML elements their natural shape, and make our sites more readable by default. When we start a project with a reset or normalization stylesheet, it's the UA styles that we are re-setting or normalizing. But how can we see these UA styles? Miriam Suzanne will show you how to find them online, inside Firefox itself, or even in developer tools as we debug our site styles.
- Firefox: resource://gre-resources/html.css or hg.mozilla.org/mozilla-central/file/tip/layout/style/res/html.css
- Chrome: chromium.googlesource.com/chromium/blink/+/master/Source/core/css/html.css
- Webkit: trac.webkit.org/browser/trunk/Source/WebCore/css/html.css
- More: meiert.com/en/blog/user-agent-style-sheets
#css #miriamsuzanne #firefoxdevtools
Not sure where that default 8px of margin on the body comes from? Here's how to find out!
Every browser provides a User Agent (UA) Stylesheet to give HTML elements their natural shape, and make our sites more readable by default. When we start a project with a reset or normalization stylesheet, it's the UA styles that we are re-setting or normalizing. But how can we see these UA styles? Miriam Suzanne will show you how to find them online, inside Firefox itself, or even in developer tools as we debug our site styles.
- Firefox: resource://gre-resources/html.css or hg.mozilla.org/mozilla-central/file/tip/layout/style/res/html.css
- Chrome: chromium.googlesource.com/chromium/blink/+/master/Source/core/css/html.css
- Webkit: trac.webkit.org/browser/trunk/Source/WebCore/css/html.css
- More: meiert.com/en/blog/user-agent-style-sheets
#css #miriamsuzanne #firefoxdevtools
