Button animation with Keyframe?

Question

css

Can you please tell me how to make such an animation using keyframe ?

Animation example - https://codepen.io/Zeaklous/pen/kyGqm

My attempts - https://codepen.io/forcifer21/pen/rNOEbGV?editors=1100
Many thanks in advance

Answer 1

https://codepen.io/devilishalchemist/pen/oXjYKB
https://freefrontend.com/css-border-animations/