Make an animated glowing border effect with CSS

I was recently asked about creating the glowing border effect from Google's AI Mode, and it sounded like a fun challenge, so here's how I did it!

🔗 Links
✅ Finished code: https://codepen.io/kevinpowell/pen/Wb...
✅ The site where I got the effect: https://search.google/ways-to-search/...

https://kevinpowell.co/courses

⌚ Timestamps
00:00 - Introduction
00:30 - the HTML and starting CSS
01:30 - Setting up the border
06:48 - Faking a transparent background
09:00 - Adding the outer glow
13:20 - Making the inner glow
16:55 - Tweaking the values of the blur
18:18 - Adding custom properties
20:07 - Flipping it to the other side
22:25 - Improving and customizing the gradient
24:30 - Animating the gradient and glow by changing the colors
27:35 - An easier way to animate it

#css

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