=== Test 1: Content change inside abspos doesn't affect fit-content ancestor ===
Initial width: 210
After abspos content change: 210
PASS: true

=== Test 2: Content change in in-flow element DOES affect ancestor ===
Initial width: 95
After in-flow content change: 609
PASS: true

=== Test 3: Position toggle static to absolute shrinks container ===
Initial width: 210
After static->absolute: 110
PASS: true

=== Test 4: Position toggle absolute to static grows container ===
Initial width: 110
After absolute->static: 210
PASS: true

=== Test 5: Nested abspos - outer container unaffected ===
Initial width: 110
After nested abspos content change: 110
PASS: true

=== Test 6: Fixed position element (also abspos) doesn't affect ancestor ===
Initial width: 210
After fixed content change: 210
PASS: true

=== Test 7: In-flow sibling of abspos DOES affect ancestor ===
Initial width: 120
After sibling content change: 598
PASS: true

=== Test 8: Abspos with fit-content updates its own size ===
Initial abspos width: 151
After content change abspos width: 405
Container width (should be ~210): 210
PASS abspos grew: true
PASS container unchanged: true

=== Test 9: Transform containing block - abspos inside doesn't affect outer ===
Initial width: 110
After content change: 110
PASS: true

=== Test 10: Flex container - abspos child doesn't affect flex sizing ===
Initial width: 110
After content change: 110
PASS: true