The Add User dialog was see-through over its own overlay in dark mode. Both it
and the audit-log detail dialog set background: var(--bg-card), which is
translucent in dark mode - frontend/CLAUDE.md already names this trap and says
a modal panel must use var(--bg-card-solid). The shared Modal.vue and the
.modal rule in style.css were already correct; these two hand-rolled panels
were not.
Audited every modal-ish panel in the app while here. The remaining
var(--bg-card) uses are correct and deliberate: .relationships-section and
.permission-category are cards, and the audit-log .filters rules are form
controls - translucency is the intended look on all of them.
One more was worth changing: the warranty asset-search dropdown floats above
the form INSIDE a modal, so a translucent panel let the fields show through the
suggestions. That one is now solid too.