How to make such a hover effect without js?

Question

css

riccardozanutta.com

Answer 1

Here is an example with different colors: https://codepen.io/abnmt/pen/RMompQ

Answer 2

Lines do through :before/:after and assign them a transition and zero width
on :hover change the width of the lines

Answer 3

https://codepen.io/aeronaut/pen/oqYzYj