diff --git a/docs/INTERFACE_PATTERN_MIGRATION.md b/docs/INTERFACE_PATTERN_MIGRATION.md
index 25e35d6..895bd0a 100644
--- a/docs/INTERFACE_PATTERN_MIGRATION.md
+++ b/docs/INTERFACE_PATTERN_MIGRATION.md
@@ -29,5 +29,8 @@ submissions, receipts, and handoff execution.
 
 The module uses shared controls, dialogs, blockers, field help, statuses,
 loading, empty/error states, disabled reasons, confirmations, and unsaved-draft
-guards. Existing responsive list/editor layouts remain bounded. English and
-German catalogues cover the owned route and editor vocabulary.
+guards. The catalogue action row now uses the shared responsive
+`ActionToolbar`; equal-column definition/editor groups use `FormGrid` and its
+named narrow-layout collapse policy. These layout contracts do not change
+filter scope, permissions, revision semantics, or publication consequences.
+English and German catalogues cover the owned route and editor vocabulary.
diff --git a/src/govoplan_forms/backend/manifest.py b/src/govoplan_forms/backend/manifest.py
index 95da738..1890f92 100644
--- a/src/govoplan_forms/backend/manifest.py
+++ b/src/govoplan_forms/backend/manifest.py
@@ -194,7 +194,8 @@ manifest = ModuleManifest(
             summary="Create immutable, versioned schemas consumed by Forms Runtime and institutional services.",
             body=(
                 "Each revision fixes field types, options, constraints, draft, attachment, signature, policy, and handoff requirements. "
-                "Publishing is explicit; existing submissions continue to retain their exact revision."
+                "Publishing is explicit; existing submissions continue to retain their exact revision. The catalogue action row and "
+                "definition field groups reflow at narrow widths without changing filter scope, permissions, or lifecycle effects."
             ),
             layer="configured",
             documentation_types=("admin", "user"),
diff --git a/webui/src/features/forms/FormDefinitionDialog.tsx b/webui/src/features/forms/FormDefinitionDialog.tsx
index 2b48c5f..1106e8b 100644
--- a/webui/src/features/forms/FormDefinitionDialog.tsx
+++ b/webui/src/features/forms/FormDefinitionDialog.tsx
@@ -1,6 +1,6 @@
 import { ArrowDown, ArrowUp, Eye, Languages, Plus, Trash2 } from "lucide-react";
 import { useEffect, useMemo, useState } from "react";
-import {
+import { FormGrid,
   Button,
   ConfirmDialog,
   Dialog,
@@ -198,7 +198,7 @@ export default function FormDefinitionDialog({
       <div className="form-definition-editor">
         <div className="form-definition-help"><DocumentationHelpLink reference={FORMS_FIELD_DOCUMENTATION} /></div>
         {error && <DismissibleAlert tone="danger" resetKey={error}>{error}</DismissibleAlert>}
-        <div className="form-definition-grid">
+        <FormGrid columns={2} gap="small" collapseAt="narrow">
           <Field label="Title">
             <input value={draft.title} disabled={busy} onChange={(event) => setDraft({ ...draft, title: event.target.value })} />
           </Field>
@@ -260,7 +260,7 @@ export default function FormDefinitionDialog({
               placeholder="Optional instructions announced before the Form"
             />
           </Field>
-        </div>
+        </FormGrid>
 
         <div className="form-field-editor-heading">
           <h3>Fields</h3>
@@ -333,19 +333,19 @@ export default function FormDefinitionDialog({
 function ConstraintFields({ field, disabled, onChange }: { field: FormFieldDefinition; disabled: boolean; onChange: (value: Record<string, unknown>) => void }) {
   if (["text", "multiline_text", "email"].includes(field.value_type)) {
     return (
-      <div className="form-field-constraints">
+      <FormGrid columns={3} gap="compact" collapseAt="narrow" className="form-field-constraints">
         <Field label="Minimum length"><input type="number" min={0} value={constraintValue(field.constraints.min_length)} disabled={disabled} onChange={(event) => onChange(patchConstraint(field.constraints, "min_length", event.target.value))} /></Field>
         <Field label="Maximum length"><input type="number" min={0} value={constraintValue(field.constraints.max_length)} disabled={disabled} onChange={(event) => onChange(patchConstraint(field.constraints, "max_length", event.target.value))} /></Field>
         <Field label="Pattern"><input value={String(field.constraints.pattern ?? "")} disabled={disabled} onChange={(event) => onChange(patchTextConstraint(field.constraints, "pattern", event.target.value))} /></Field>
-      </div>
+      </FormGrid>
     );
   }
   if (["integer", "number"].includes(field.value_type)) {
     return (
-      <div className="form-field-constraints">
+      <FormGrid columns={3} gap="compact" collapseAt="narrow" className="form-field-constraints">
         <Field label="Minimum"><input type="number" value={constraintValue(field.constraints.minimum)} disabled={disabled} onChange={(event) => onChange(patchConstraint(field.constraints, "minimum", event.target.value))} /></Field>
         <Field label="Maximum"><input type="number" value={constraintValue(field.constraints.maximum)} disabled={disabled} onChange={(event) => onChange(patchConstraint(field.constraints, "maximum", event.target.value))} /></Field>
-      </div>
+      </FormGrid>
     );
   }
   return null;
@@ -367,7 +367,7 @@ function ConditionFields({
   const predicate = condition?.kind === "predicate" ? condition : null;
   const candidates = fields.filter((item) => item.key !== currentKey && item.key.trim());
   return (
-    <div className="form-field-condition">
+    <FormGrid columns={3} gap="compact" collapseAt="narrow" className="form-field-condition">
       <Field label="Visible when">
         <select
           value={predicate?.field_key ?? ""}
@@ -406,7 +406,7 @@ function ConditionFields({
           </Field>
         }
       </>}
-    </div>
+    </FormGrid>
   );
 }
 
@@ -506,7 +506,7 @@ function DefinitionPreview({ definition, previous }: { definition: FormDefinitio
   return (
     <section className="form-composition-section form-definition-preview">
       <div className="form-field-editor-heading"><h3><Eye size={17} aria-hidden="true" />Preview and revision changes</h3></div>
-      <div className="form-preview-grid">
+      <FormGrid columns={2} collapseAt="narrow" className="form-preview-grid">
         <div>
           <strong>{definition.title || "Untitled Form"}</strong>
           {(definition.pages?.length ? definition.pages : [defaultPage(definition.fields)]).map((page) =>
@@ -517,7 +517,7 @@ function DefinitionPreview({ definition, previous }: { definition: FormDefinitio
           )}
         </div>
         <div><strong>Changes</strong><ul>{changed.map((item) => <li key={item}>{item}</li>)}</ul></div>
-      </div>
+      </FormGrid>
     </section>
   );
 }
diff --git a/webui/src/features/forms/FormsPage.tsx b/webui/src/features/forms/FormsPage.tsx
index 6a9af8e..848e7f1 100644
--- a/webui/src/features/forms/FormsPage.tsx
+++ b/webui/src/features/forms/FormsPage.tsx
@@ -1,6 +1,6 @@
 import { Download, Pencil, Plus, RefreshCw, Search, Upload } from "lucide-react";
 import { useCallback, useEffect, useRef, useState, type FormEvent } from "react";
-import {
+import { ActionToolbar,
   ActionBlockerHint,
   Button,
   Dialog,
@@ -145,7 +145,7 @@ export default function FormsPage({ settings, auth }: PlatformRouteContext) {
   return (
     <main className="forms-page">
       <div className="forms-shell">
-        <div className="forms-toolbar">
+        <ActionToolbar className="forms-toolbar">
           <form onSubmit={search} className="forms-search">
             <Search size={17} aria-hidden="true" />
             <input value={query} onChange={(event) => setQuery(event.target.value)} placeholder="Search definitions" aria-label="Search Form definitions" />
@@ -166,7 +166,7 @@ export default function FormsPage({ settings, auth }: PlatformRouteContext) {
           <Button variant="primary" disabled={!canWrite} disabledReason={!canWrite ? FORMS_I18N.writeReason : undefined} onClick={() => setEditing("new")}><Plus size={16} aria-hidden="true" />New definition</Button>
           <span className="forms-count">{total}</span>
           <DocumentationHelpLink reference={FORMS_DOCUMENTATION} />
-        </div>
+        </ActionToolbar>
         <PageScrollViewport className="forms-list-viewport">
           {error && <DismissibleAlert tone="danger" resetKey={error}>{error}</DismissibleAlert>}
           {!canWrite && <ActionBlockerHint tone="info" reason={{ summary: "No Form management permission", details: FORMS_I18N.writeReason, requiredAction: FORMS_I18N.permissionAction, actor: FORMS_I18N.permissionActor, target: FORMS_I18N.permissionDestination }} labels={{ requiredAction: FORMS_I18N.requiredAction, actor: FORMS_I18N.actor, target: FORMS_I18N.destination }} documentation={FORMS_DOCUMENTATION} />}
diff --git a/webui/src/styles/forms.css b/webui/src/styles/forms.css
index 5a69d35..c89502d 100644
--- a/webui/src/styles/forms.css
+++ b/webui/src/styles/forms.css
@@ -145,12 +145,6 @@
   justify-content: flex-end;
 }
 
-.form-definition-grid {
-  display: grid;
-  grid-template-columns: repeat(2, minmax(0, 1fr));
-  gap: 12px 16px;
-}
-
 .form-definition-wide {
   grid-column: 1 / -1;
 }
@@ -229,13 +223,6 @@
   grid-column: 2 / -1;
 }
 
-.form-field-constraints,
-.form-field-condition {
-  display: grid;
-  grid-template-columns: repeat(3, minmax(0, 1fr));
-  gap: 9px;
-}
-
 .form-composition-section {
   display: flex;
   flex-direction: column;
@@ -302,9 +289,7 @@
 }
 
 .form-preview-grid {
-  display: grid;
-  grid-template-columns: repeat(2, minmax(0, 1fr));
-  gap: 18px;
+  min-width: 0;
 }
 
 .form-preview-grid > div {
@@ -374,14 +359,10 @@
 }
 
 @media (max-width: 620px) {
-  .form-definition-grid,
-  .form-field-constraints,
-  .form-field-condition,
   .form-page-editor-heading,
   .form-section-editor,
   .form-localization-editor,
-  .form-localization-fields,
-  .form-preview-grid {
+  .form-localization-fields {
     grid-template-columns: 1fr;
   }