Nested CSS selectors?

Question

css

Trying to improve my HTML+CSS code, gradually learning BEM, I wondered how to properly organize descendant selectors?
UPD: the only correct option, apparently:

.block{
    &__header{}
    &__text{}
}

Answer 1

you have now described cases that can be implemented in SCSS. And a record like:

.block{
    .block__header{}
    .block__text{}
}

still recompiled to CSS like this:

.block{}
.block .block__header{}
.block .block__text{}

You can also write:

.block{
    &__header{}
    &__text{}
}

that would be more correct.