diff --git a/frontend/src/components/calendar/CalendarPage.tsx b/frontend/src/components/calendar/CalendarPage.tsx
index dc58d13..dff063a 100644
--- a/frontend/src/components/calendar/CalendarPage.tsx
+++ b/frontend/src/components/calendar/CalendarPage.tsx
@@ -187,12 +187,13 @@ export default function CalendarPage() {
     return () => cancelAnimationFrame(rafId);
   }, [panelOpen]);
 
-  // Scroll wheel navigation in month view
+  // Scroll wheel navigation in month view (disabled when detail panel is open)
   useEffect(() => {
     const el = calendarContainerRef.current;
     if (!el) return;
     let debounceTimer: ReturnType<typeof setTimeout> | null = null;
     const handleWheel = (e: WheelEvent) => {
+      if (panelOpen) return;
       // Skip wheel navigation on touch devices (let them scroll normally)
       if ('ontouchstart' in window) return;
       const api = calendarRef.current?.getApi();
@@ -207,7 +208,7 @@ export default function CalendarPage() {
     };
     el.addEventListener('wheel', handleWheel, { passive: false });
     return () => el.removeEventListener('wheel', handleWheel);
-  }, []);
+  }, [panelOpen]);
 
   // AW-2: Track visible date range for scoped event fetching
   // W-02 fix: Initialize from current month to avoid unscoped first fetch
diff --git a/frontend/src/components/calendar/EventDetailPanel.tsx b/frontend/src/components/calendar/EventDetailPanel.tsx
index b8e08e8..541c7ed 100644
--- a/frontend/src/components/calendar/EventDetailPanel.tsx
+++ b/frontend/src/components/calendar/EventDetailPanel.tsx
@@ -1,4 +1,4 @@
-import { useState, useEffect, useCallback, useMemo } from 'react';
+import { useState, useEffect, useCallback, useMemo, useRef } from 'react';
 import { useMutation, useQuery, useQueryClient } from '@tanstack/react-query';
 import { toast } from 'sonner';
 import { format, parseISO } from 'date-fns';
@@ -284,6 +284,17 @@ export default function EventDetailPanel({
   const [scopeStep, setScopeStep] = useState<'edit' | 'delete' | null>(null);
   const [editScope, setEditScope] = useState<'this' | 'this_and_future' | null>(null);
   const [locationSearch, setLocationSearch] = useState('');
+  const descRef = useRef<HTMLTextAreaElement>(null);
+
+  // Auto-resize description textarea to fit content
+  useEffect(() => {
+    const el = descRef.current;
+    if (!el) return;
+    requestAnimationFrame(() => {
+      el.style.height = 'auto';
+      el.style.height = `${el.scrollHeight}px`;
+    });
+  }, [editState.description, isEditing]);
 
   // Poll lock status in view mode for shared events (Stream A: real-time lock awareness)
   // lockInfo is only set from the 423 error path; poll data (viewLockQuery.data) is used directly.
@@ -367,11 +378,11 @@ export default function EventDetailPanel({
         end_datetime: endDt,
         all_day: data.all_day,
         location_id: data.location_id ? parseInt(data.location_id) : null,
-        is_starred: data.is_starred,
-        recurrence_rule: rule,
       };
-      // Invited editors cannot change calendars — omit calendar_id from payload
+      // Invited editors are restricted to the backend allowlist — omit fields they cannot modify
       if (!canModifyAsInvitee) {
+        payload.is_starred = data.is_starred;
+        payload.recurrence_rule = rule;
         payload.calendar_id = data.calendar_id ? parseInt(data.calendar_id) : null;
       }
 
@@ -539,7 +550,8 @@ export default function EventDetailPanel({
     : event?.title || '';
 
   return (
-    <div className="flex flex-col h-full bg-card border-l border-border overflow-hidden">
+    // onWheel stopPropagation: defence-in-depth with CalendarPage's panelOpen guard to prevent month-scroll bleed
+    <div className="flex flex-col h-full bg-card border-l border-border overflow-hidden" onWheel={(e) => e.stopPropagation()}>
       {/* Header */}
       <div className="px-5 py-4 border-b border-border shrink-0">
         <div className="flex items-start justify-between gap-3">
@@ -721,7 +733,7 @@ export default function EventDetailPanel({
           </div>
         ) : (isEditing || isCreating) ? (
           /* Edit / Create mode */
-          <div className="space-y-4">
+          <div className="flex flex-col gap-3 h-full">
             {/* Title (only shown in body for create mode; edit mode has it in header) */}
             {isCreating && (
               <div className="space-y-1">
@@ -737,58 +749,49 @@ export default function EventDetailPanel({
               </div>
             )}
 
-            <div className="space-y-1">
-              <Label htmlFor="panel-desc">Description</Label>
-              <Textarea
-                id="panel-desc"
-                value={editState.description}
-                onChange={(e) => updateField('description', e.target.value)}
-                placeholder="Add a description..."
-                rows={3}
-                className="text-sm resize-none"
-              />
-            </div>
-
-            <div className="flex items-center gap-2">
-              <Checkbox
-                id="panel-allday"
-                checked={editState.all_day}
-                onChange={(e) => {
-                  const checked = (e.target as HTMLInputElement).checked;
-                  updateField('all_day', checked);
-                  updateField('start_datetime', formatForInput(editState.start_datetime, checked, '09:00'));
-                  updateField('end_datetime', formatForInput(editState.end_datetime, checked, '10:00'));
-                }}
-              />
-              <Label htmlFor="panel-allday">All day event</Label>
-            </div>
-
-            <div className="grid grid-cols-2 gap-3">
-              <div className="space-y-1">
-                <Label htmlFor="panel-start" required>Start</Label>
-                <DatePicker
-                  variant="input"
-                  id="panel-start"
-                  mode={editState.all_day ? 'date' : 'datetime'}
-                  value={editState.start_datetime}
-                  onChange={(v) => updateField('start_datetime', v)}
-                  className="text-xs"
-                  required
+            {/* All day + Date row */}
+            <div className="space-y-2">
+              <div className="flex items-center gap-2">
+                <Checkbox
+                  id="panel-allday"
+                  checked={editState.all_day}
+                  onChange={(e) => {
+                    const checked = (e.target as HTMLInputElement).checked;
+                    updateField('all_day', checked);
+                    updateField('start_datetime', formatForInput(editState.start_datetime, checked, '09:00'));
+                    updateField('end_datetime', formatForInput(editState.end_datetime, checked, '10:00'));
+                  }}
                 />
+                <Label htmlFor="panel-allday" className="text-xs">All day</Label>
               </div>
-              <div className="space-y-1">
-                <Label htmlFor="panel-end">End</Label>
-                <DatePicker
-                  variant="input"
-                  id="panel-end"
-                  mode={editState.all_day ? 'date' : 'datetime'}
-                  value={editState.end_datetime}
-                  onChange={(v) => updateField('end_datetime', v)}
-                  className="text-xs"
-                />
+              <div className="grid grid-cols-2 gap-3">
+                <div className="space-y-1">
+                  <Label htmlFor="panel-start" required>Start</Label>
+                  <DatePicker
+                    variant="input"
+                    id="panel-start"
+                    mode={editState.all_day ? 'date' : 'datetime'}
+                    value={editState.start_datetime}
+                    onChange={(v) => updateField('start_datetime', v)}
+                    className="text-xs"
+                    required
+                  />
+                </div>
+                <div className="space-y-1">
+                  <Label htmlFor="panel-end">End</Label>
+                  <DatePicker
+                    variant="input"
+                    id="panel-end"
+                    mode={editState.all_day ? 'date' : 'datetime'}
+                    value={editState.end_datetime}
+                    onChange={(v) => updateField('end_datetime', v)}
+                    className="text-xs"
+                  />
+                </div>
               </div>
             </div>
 
+            {/* Calendar + Location row */}
             <div className={`grid ${canModifyAsInvitee ? 'grid-cols-1' : 'grid-cols-2'} gap-3`}>
               {!canModifyAsInvitee && (
                 <div className="space-y-1">
@@ -837,22 +840,32 @@ export default function EventDetailPanel({
               </div>
             </div>
 
-            {/* Recurrence — hidden for invited editors (they can only edit "this" occurrence) */}
+            {/* Recurrence + Star row */}
             {!canModifyAsInvitee && (
-              <div className="space-y-1">
-                <Label htmlFor="panel-recurrence">Recurrence</Label>
-                <Select
-                  id="panel-recurrence"
-                  value={editState.recurrence_type}
-                  onChange={(e) => updateField('recurrence_type', e.target.value)}
-                  className="text-xs"
-                >
-                  <option value="">None</option>
-                  <option value="every_n_days">Every X days</option>
-                  <option value="weekly">Weekly</option>
-                  <option value="monthly_nth_weekday">Monthly (nth weekday)</option>
-                  <option value="monthly_date">Monthly (date)</option>
-                </Select>
+              <div className="grid grid-cols-2 gap-3 items-end">
+                <div className="space-y-1">
+                  <Label htmlFor="panel-recurrence">Recurrence</Label>
+                  <Select
+                    id="panel-recurrence"
+                    value={editState.recurrence_type}
+                    onChange={(e) => updateField('recurrence_type', e.target.value)}
+                    className="text-xs"
+                  >
+                    <option value="">None</option>
+                    <option value="every_n_days">Every X days</option>
+                    <option value="weekly">Weekly</option>
+                    <option value="monthly_nth_weekday">Monthly (nth weekday)</option>
+                    <option value="monthly_date">Monthly (date)</option>
+                  </Select>
+                </div>
+                <div className="flex items-center gap-2 pb-2">
+                  <Checkbox
+                    id="panel-starred"
+                    checked={editState.is_starred}
+                    onChange={(e) => updateField('is_starred', (e.target as HTMLInputElement).checked)}
+                  />
+                  <Label htmlFor="panel-starred" className="text-xs">Starred</Label>
+                </div>
               </div>
             )}
 
@@ -924,23 +937,17 @@ export default function EventDetailPanel({
               </div>
             )}
 
-            <div className="flex items-center gap-2">
-              <Checkbox
-                id="panel-starred"
-                checked={editState.is_starred}
-                onChange={(e) => updateField('is_starred', (e.target as HTMLInputElement).checked)}
+            {/* Description — fills remaining space */}
+            <div className="flex flex-col flex-1 min-h-0 space-y-1">
+              <Label htmlFor="panel-desc">Description</Label>
+              <Textarea
+                ref={descRef}
+                id="panel-desc"
+                value={editState.description}
+                onChange={(e) => updateField('description', e.target.value)}
+                placeholder="Add a description..."
+                className="text-sm flex-1 min-h-[80px]"
               />
-              <Label htmlFor="panel-starred">Star this event</Label>
-            </div>
-
-            {/* Save / Cancel buttons at bottom of form */}
-            <div className="flex items-center justify-end gap-2 pt-2 border-t border-border">
-              <Button variant="outline" size="sm" onClick={handleEditCancel}>
-                Cancel
-              </Button>
-              <Button size="sm" onClick={handleEditSave} disabled={saveMutation.isPending}>
-                {saveMutation.isPending ? 'Saving...' : isCreating ? 'Create' : 'Update'}
-              </Button>
             </div>
           </div>
         ) : (
@@ -1056,15 +1063,17 @@ export default function EventDetailPanel({
             </div>
 
             {/* Description — full width */}
-            {event?.description && (
-              <div className="space-y-1">
-                <div className="flex items-center gap-1.5 text-[11px] text-muted-foreground uppercase tracking-wider">
-                  <AlignLeft className="h-3 w-3" />
-                  Description
-                </div>
-                <p className="text-sm whitespace-pre-wrap">{event.description}</p>
+            <div className="space-y-1">
+              <div className="flex items-center gap-1.5 text-[11px] text-muted-foreground uppercase tracking-wider">
+                <AlignLeft className="h-3 w-3" />
+                Description
               </div>
-            )}
+              {event?.description ? (
+                <p className="text-sm whitespace-pre-wrap">{event.description}</p>
+              ) : (
+                <p className="text-sm text-muted-foreground">—</p>
+              )}
+            </div>
 
             {/* Invitee section — view mode */}
             {event && !event.is_virtual && (
diff --git a/frontend/src/components/calendar/EventForm.tsx b/frontend/src/components/calendar/EventForm.tsx
index 4bae0fc..2884b88 100644
--- a/frontend/src/components/calendar/EventForm.tsx
+++ b/frontend/src/components/calendar/EventForm.tsx
@@ -1,4 +1,4 @@
-import { useState, FormEvent } from 'react';
+import { useState, useEffect, useRef, FormEvent } from 'react';
 import { useMutation, useQuery, useQueryClient } from '@tanstack/react-query';
 import { toast } from 'sonner';
 import api, { getErrorMessage } from '@/lib/api';
@@ -141,6 +141,17 @@ export default function EventForm({ event, templateData, templateName, initialSt
   const existingLocation = locations.find((l) => l.id === source?.location_id);
   const [locationSearch, setLocationSearch] = useState(existingLocation?.name || '');
 
+  // Auto-resize description textarea
+  const descRef = useRef<HTMLTextAreaElement>(null);
+  useEffect(() => {
+    const el = descRef.current;
+    if (!el) return;
+    requestAnimationFrame(() => {
+      el.style.height = 'auto';
+      el.style.height = `${el.scrollHeight}px`;
+    });
+  }, [formData.description]);
+
   const selectableCalendars = calendars.filter((c) => !c.is_system);
 
   const buildRecurrenceRule = (): RecurrenceRule | null => {
@@ -255,10 +266,12 @@ export default function EventForm({ event, templateData, templateName, initialSt
             <div className="space-y-2">
               <Label htmlFor="description">Description</Label>
               <Textarea
+                ref={descRef}
                 id="description"
                 value={formData.description}
                 onChange={(e) => setFormData({ ...formData, description: e.target.value })}
-                className="min-h-[80px] flex-1"
+                placeholder="Add a description..."
+                className="min-h-[80px] text-sm"
               />
             </div>