Polish export system density

frontend/src/styles/app.css

@@ -1766,6 +1766,60 @@ button.entity-card {
   margin: 0.8rem 0;
 }
 
+.export-center-shell,
+.system-provider-shell {
+  display: grid;
+  gap: 0.85rem;
+  min-width: 0;
+}
+
+.export-summary-surface,
+.export-handoff-surface,
+.export-actions-surface,
+.export-history-surface,
+.system-provider-capability-surface {
+  display: grid;
+  gap: 0.68rem;
+  min-width: 0;
+  border: 1px solid var(--line);
+  border-radius: 8px;
+  padding: 0.78rem;
+  background: linear-gradient(180deg, #ffffff, #f7fbf8);
+  box-shadow: 0 1px 0 rgba(19, 32, 24, 0.03);
+}
+
+.export-history-surface,
+.system-provider-capability-surface {
+  background: #ffffff;
+}
+
+.export-center-shell .quality-summary-grid {
+  display: grid;
+  grid-template-columns: repeat(auto-fit, minmax(8rem, 1fr));
+  gap: 0.58rem;
+  margin: 0;
+}
+
+.export-handoff-surface .handoff-summary-card {
+  margin-top: 0;
+  border: 0;
+  padding: 0;
+  background: transparent;
+  box-shadow: none;
+}
+
+.export-actions-surface .export-action-grid {
+  margin: 0;
+}
+
+.export-state-stack,
+.system-provider-state-stack,
+.provider-detail-stack {
+  display: grid;
+  gap: 0.5rem;
+  min-width: 0;
+}
+
 .export-action-grid button {
   min-height: 2.8rem;
   text-align: left;
@@ -2045,6 +2099,43 @@ button.entity-card {
   font-weight: 800;
 }
 
+.provider-detail-stack {
+  color: var(--muted);
+  font-size: 0.84rem;
+  line-height: 1.36;
+}
+
+.provider-provenance-grid {
+  display: grid;
+  grid-template-columns: repeat(auto-fit, minmax(8rem, 1fr));
+  gap: 0.5rem;
+}
+
+.provider-provenance-card {
+  min-width: 0;
+  border: 1px solid rgba(15, 118, 110, 0.16);
+  border-radius: 7px;
+  padding: 0.55rem;
+  background: #ffffff;
+}
+
+.provider-provenance-card span {
+  display: block;
+  color: var(--muted);
+  font-size: 0.68rem;
+  font-weight: 800;
+  letter-spacing: 0.05em;
+  text-transform: uppercase;
+}
+
+.provider-provenance-card strong {
+  display: block;
+  margin-top: 0.18rem;
+  overflow-wrap: anywhere;
+  font-size: 0.88rem;
+  line-height: 1.25;
+}
+
 .export-preview-panel .job-result {
   max-height: 38rem;
 }