CSS - 课前的星号是什么意思？

Question

.some_class{} 和 *.some_class{} 有什么区别。

这是否意味着该类仅应用于另一个标签内的标签，还是根本没有区别？

Answer 1

没有区别 - 请参阅 here

The universal selector, written "*", matches the name of any element type. It matches any single element in the document tree.

If the universal selector is not the only component of a simple selector, the "*" may be omitted. For example:

*[lang=fr] and [lang=fr] are equivalent.
*.warning and .warning are equivalent.
*#myid and #myid are equivalent.