Uploaded July 2026 | Updated September 2026, 2 weeks ago
👉 Start writing CSS with confidence: https://thecascade.dev/courses/css-demystified/?utm_source=youtube&utm_medium=social&utm_campaign=regular-video
🔗 Links
✅ The finished code from this video: codepen.io/editor/kevinpowell/pen/019edff0-144f-762c-85f3-9483030c56f4
✅ Manuel’s better popover defaults post: https://matuzo.at/blog/2026/better-defaults-for-popovers
✅ Oddbird’s dos & don’ts of anchor positioning: oddbird.net/2026/04/16/winging-it-31
✅ Oddbird’sHere’s why your anchor positioning isn’t working: oddbird.net/2025/01/29/anchor-position-validity
✅ Anchor positioning polyfill: anchor-positioning.oddbird.net
✉ Keep up to date with everything I'm up to kevinpowell.co/newsletter
💬 Come hang out with other devs in my Discord Community discord.gg/nTYCvrK
⭐ Are you a beginner? HTML & CSS for absolute beginners is for you: learn.kevinpowell.co
🎓 Start writing CSS with confidence with CSS Demystified: cssdemystified.com
🚀 Already mastered CSS? Check out my advanced course, Beyond CSS: https://www.beyondcss.dev/
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Help support my channel
👨🎓 Get a course: kevinpowell.co/courses
👕 Buy a shirt: cottonbureau.com/people/kevin-powell
💖 Support me on Patreon: patreon.com/kevinpowell or through YT memberships: youtube.com/@KevinPowell/join
---
🧑💻 My editors:
In most videos, I’m using CodePen these days: codepen.io - with High Contrast Dark theme and the font Commit Mono
And if not CodePen, then I’m probably using Zed: https://zed.dev/ with the theme Ayu Dark, and the font ZedMono
In older videos, I was using VS Code - code.visualstudio.com with the theme One Dark Pro Var, and the font Cascadia
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⌚ Timestamps:
00:00 - Intro
00:08 - The HTML
02:22 - The user agent styles can get in the way
03:42 - Some simple overwrites you might want to use
06:05 - Positioning the popover relative to the button
07:08 - Fallbacks for when the position doesn’t fit
09:18 - Use :popover-open if you want a different display type
10:18 - Adding opening and closing transitions
15:13 - Fixing my grid columns when it closes
---
I'm on some other places on the internet too!
If you'd like a behind the scenes and previews of what's coming up on my YouTube channel:
Bluesky: https://bsky.app/profile/kevinpowell.co
Codepen: codepen.io/kevinpowell
Github: github.com/kevin-powell
---
And whatever you do, don't forget to keep on making your corner of the internet just a little bit more awesome!
#css
👉 Start writing CSS with confidence: https://thecascade.dev/courses/css-demystified/?utm_source=youtube&utm_medium=social&utm_campaign=regular-video
🔗 Links
✅ The finished code from this video: codepen.io/editor/kevinpowell/pen/019edff0-144f-762c-85f3-9483030c56f4
✅ Manuel’s better popover defaults post: https://matuzo.at/blog/2026/better-defaults-for-popovers
✅ Oddbird’s dos & don’ts of anchor positioning: oddbird.net/2026/04/16/winging-it-31
✅ Oddbird’sHere’s why your anchor positioning isn’t working: oddbird.net/2025/01/29/anchor-position-validity
✅ Anchor positioning polyfill: anchor-positioning.oddbird.net
✉ Keep up to date with everything I'm up to kevinpowell.co/newsletter
💬 Come hang out with other devs in my Discord Community discord.gg/nTYCvrK
⭐ Are you a beginner? HTML & CSS for absolute beginners is for you: learn.kevinpowell.co
🎓 Start writing CSS with confidence with CSS Demystified: cssdemystified.com
🚀 Already mastered CSS? Check out my advanced course, Beyond CSS: https://www.beyondcss.dev/
---
Help support my channel
👨🎓 Get a course: kevinpowell.co/courses
👕 Buy a shirt: cottonbureau.com/people/kevin-powell
💖 Support me on Patreon: patreon.com/kevinpowell or through YT memberships: youtube.com/@KevinPowell/join
---
🧑💻 My editors:
In most videos, I’m using CodePen these days: codepen.io - with High Contrast Dark theme and the font Commit Mono
And if not CodePen, then I’m probably using Zed: https://zed.dev/ with the theme Ayu Dark, and the font ZedMono
In older videos, I was using VS Code - code.visualstudio.com with the theme One Dark Pro Var, and the font Cascadia
---
⌚ Timestamps:
00:00 - Intro
00:08 - The HTML
02:22 - The user agent styles can get in the way
03:42 - Some simple overwrites you might want to use
06:05 - Positioning the popover relative to the button
07:08 - Fallbacks for when the position doesn’t fit
09:18 - Use :popover-open if you want a different display type
10:18 - Adding opening and closing transitions
15:13 - Fixing my grid columns when it closes
---
I'm on some other places on the internet too!
If you'd like a behind the scenes and previews of what's coming up on my YouTube channel:
Bluesky: https://bsky.app/profile/kevinpowell.co
Codepen: codepen.io/kevinpowell
Github: github.com/kevin-powell
---
And whatever you do, don't forget to keep on making your corner of the internet just a little bit more awesome!
#css
