Example: insert lb.html into index.html, and lb.html has a lb.css.

Problem: at this time, index.html may report an error: refuse to apply styles from lb.css. But it’s all normal. No problem.

Attempt failed: Online modifications…/modifications, etc. are invalid here. If we start with index.html and introduce the address of lb.css into lb.html, index.html will not report an error, but lb.html will report an error and so on.

Current method: put lb.css and index.css in the same CSS folder and reference them normally. Index.html and lb.html will not report errors.