Graph calculator improvmentes

frontend/app/assets/css/_graph.scss

@@ -120,3 +120,30 @@
 
   .graph-state { position: static; display: block; padding: 8px 0 32px; }
 }
+
+// ---------- Laid on a page of the book (ToolPane) ----------
+// A pane of the book is a full surface again, at any screen width: the map
+// fills the page the way it fills the desk, and the fold above — panels of
+// the plain /graph page — does not reach into the pane.
+
+.pane-stage .graph-stage {
+  position: absolute;
+  inset: 0;
+  background: var(--bg);
+}
+
+.pane-stage .graph-canvas-wrap {
+  position: absolute;
+  height: auto;
+  margin: 0;
+  border: 0;
+  border-radius: 0;
+  box-shadow: none;
+}
+
+.pane-stage .graph-state {
+  position: absolute;
+  inset: 0;
+  display: grid;
+  padding: 24px;
+}