What is the correct way to add a property to a block child via ::before for a :last-child element with a specific class name?

Question

css

What is the correct way to add a property to a block child via ::before for a :last-child element with a specific class name?
sample code here : https://codepen.io/Simonz/pen/NjqWJw
the markup is dynamic, the number of children changes, it is necessary that the last element with the v-has-height class, the ::before pseudo-element has a limited height

Answer 1

do you add new elements through js? if so, remove the last class from all v-has-height from the beginning, then you can find the element eg. through
and assign the class last
or even easier through jquery
if not, then just give the last class last (in the html code) and give it styles already:

& > .v-panel.v-has-height.last {
    &::before {}
}

Answer 2

there is no way to change the markup, js is not allowed =(