#selector-max-compound-selectors

限制一个选择器中复合选择器的数量

   div .bar[data-val] > a.baz + .boom > #lorem {}
/* ↑   ↑                ↑       ↑       ↑
   ↑   ↑                ↑       ↑       ↑
  Lv1 Lv2              Lv3     Lv4     Lv5  -- these are compound selectors */

A compound selector is a chain of one or more simple (tag, class, ID, universal, attribute) selectors. If there is more than one compound selector in a complete selector, they will be separated by combinators (e.g. , +, >). One reason why you might want to limit the number of compound selectors is described in the SMACSS book.

此规则在计算一个选择器的深度之前先解析选择器嵌套。选择器列表中的每个选择器都将单独计算。

:not() is considered one compound selector irrespective to the complexity of the selector inside it. The rule does process that inner selector, but does so separately, independent of the main selector.

#选项

int：允许的最大复合选择器数量。

例如，使用 3：

以下模式被视为违规：

.foo .bar .baz .lorem {}

.foo .baz {
  & > .bar .lorem {}
}

以下模式不被视为违规：

div {}

.foo div {}

#foo #bar > #baz {}

.foo + div :not (a b ~ c) {} /* `a b ~ c`:not()` 里面，所以它是单独计算的 */