static/style.css no longer holds every rule. 79 rules for the document,
gallery and editor panels now live in static/css/, yet 27 browser tests still
built their synthetic page with a single <link> to style.css, and 51 more read
that one file as though it were the whole cascade. Those tests kept passing
while covering less: a rule that moved became invisible to the assertion that
was meant to pin it.
Python readers now call tests.helpers.stylesheets.app_css(), and synthetic
pages are built from stylesheet_link_tags() so they load exactly what
index.html loads, in the same order. The helper already existed; this moves
the remaining callers onto it.
test_portal_dropdown_z_js parametrised over a file list including style.css to
assert an absence. Checking a negative against one file of a split stylesheet
is how a moved rule escapes, so the CSS case now checks the concatenation.
Two guards keep it from coming back: one fails on any test reading
static/style.css directly, the other on any synthetic page linking it alone.
Both name the helper to use.
No production code changes. Suite is unchanged at 6 pre-existing failures.
The timeline's terminating dot used a single left offset (-17px) at both
breakpoints, but the thread's padding-left differs (22px desktop, 18px
mobile) and the step dots already carry a per-breakpoint offset. The 6px
dot therefore landed 2px right of the 2px rail on desktop and 2px left of
it on mobile, which is the visible kink under an expanded last step.
Derive each offset from the rail's centre instead: the rail sits at
left:5px and is 2px wide, so the dot's left edge belongs at 3px, giving
3px - padding-left per breakpoint.
Léo