Debugging and review
Bisect a CSS problem
Isolate a difficult styling bug by disabling half the possible causes, repeating the test, and reducing the page to a minimal reproduction.
8 minute lesson
When many rules could cause a bug, bisect them.
Disable half the relevant stylesheet or component rules. If the problem remains, the cause is in the enabled half. If it disappears, the cause is in the disabled half. Repeat until one small group remains.
Then create a minimal reproduction with only the necessary HTML and CSS. Remove wrappers, properties, and content one at a time while keeping the bug.
This process reveals interactions that are hard to spot in a full application: a containing block created by a transform, a flex item minimum, a stacking context, or an inherited custom property.
Keep the reduced example as a regression test or note when the bug could return.
Lesson completed