desktop: polish chat timeline, header, and channel layout

- Subtler day dividers and compact date headings; remove chat header border
- Reposition scroll-to-latest above composer with muted outline style
- Channel pane/screen layout and related sheet/sidebar tweaks

Made-with: Cursor

desktop/src/features/channels/ui/ChannelManagementSheet.tsx

@@ -210,7 +210,7 @@ export function ChannelManagementSheet({
   return (
     <Sheet onOpenChange={handleSheetOpenChange} open={open}>
       <SheetContent
-        className="flex w-full flex-col gap-0 overflow-hidden border-l border-border/80 bg-background p-0 sm:max-w-xl"
+        className="flex w-full flex-col gap-0 overflow-hidden bg-background p-0 sm:max-w-xl"
         data-testid="channel-management-sheet"
         side="right"
       >

desktop/src/features/channels/ui/ChannelPane.tsx

@@ -71,7 +71,7 @@ export const ChannelPane = React.memo(function ChannelPane({
   typingPubkeys,
 }: ChannelPaneProps) {
   return (
-    <>
+    <div className="relative flex min-h-0 min-w-0 flex-1 flex-col overflow-hidden">
       <MessageTimeline
         channelId={activeChannel?.id}
         activeReplyTargetId={replyTargetId}
@@ -101,49 +101,51 @@ export const ChannelPane = React.memo(function ChannelPane({
         onToggleReaction={onToggleReaction}
         targetMessageId={targetMessageId}
       />
-      <TypingIndicatorRow
-        channel={activeChannel}
-        currentPubkey={currentPubkey}
-        profiles={profiles}
-        typingPubkeys={typingPubkeys}
-      />
-      <MessageComposer
-        channelId={activeChannel?.id ?? null}
-        channelName={activeChannel?.name ?? "channel"}
-        disabled={
-          !activeChannel ||
-          !activeChannel.isMember ||
-          activeChannel.archivedAt !== null ||
-          activeChannel.channelType === "forum" ||
-          isSending
-        }
-        editTarget={editTarget}
-        isSending={isSending}
-        onCancelEdit={onCancelEdit}
-        onCancelReply={onCancelReply}
-        onEditSave={onEditSave}
-        onSend={onSend}
-        placeholder={
-          activeChannel?.archivedAt
-            ? "Archived channels are read-only."
-            : activeChannel && !activeChannel.isMember
-              ? "Join this channel to message."
-              : activeChannel?.channelType === "forum"
-                ? "Forum posting is not wired in this pass."
-                : activeChannel
-                  ? `Message #${activeChannel.name}`
-                  : "Select a channel"
-        }
-        replyTarget={
-          replyTargetMessage
-            ? {
-                author: replyTargetMessage.author,
-                body: replyTargetMessage.body,
-                id: replyTargetMessage.id,
-              }
-            : null
-        }
-      />
-    </>
+      <div className="relative z-10 -mt-10 shrink-0">
+        <TypingIndicatorRow
+          channel={activeChannel}
+          currentPubkey={currentPubkey}
+          profiles={profiles}
+          typingPubkeys={typingPubkeys}
+        />
+        <MessageComposer
+          channelId={activeChannel?.id ?? null}
+          channelName={activeChannel?.name ?? "channel"}
+          disabled={
+            !activeChannel ||
+            !activeChannel.isMember ||
+            activeChannel.archivedAt !== null ||
+            activeChannel.channelType === "forum" ||
+            isSending
+          }
+          editTarget={editTarget}
+          isSending={isSending}
+          onCancelEdit={onCancelEdit}
+          onCancelReply={onCancelReply}
+          onEditSave={onEditSave}
+          onSend={onSend}
+          placeholder={
+            activeChannel?.archivedAt
+              ? "Archived channels are read-only."
+              : activeChannel && !activeChannel.isMember
+                ? "Join this channel to message."
+                : activeChannel?.channelType === "forum"
+                  ? "Forum posting is not wired in this pass."
+                  : activeChannel
+                    ? `Message #${activeChannel.name}`
+                    : "Select a channel"
+          }
+          replyTarget={
+            replyTargetMessage
+              ? {
+                  author: replyTargetMessage.author,
+                  body: replyTargetMessage.body,
+                  id: replyTargetMessage.id,
+                }
+              : null
+          }
+        />
+      </div>
+    </div>
   );
 });

desktop/src/features/channels/ui/ChannelScreen.tsx

@@ -343,92 +343,95 @@ export function ChannelScreen({
 
   return (
     <>
-      <ChatHeader
-        actions={
-          activeChannel ? (
-            <ChannelMembersBar
-              channel={activeChannel}
-              currentPubkey={currentPubkey}
-              onManageChannel={onManageChannel}
-              onToggleMembers={() => setIsMembersSidebarOpen((prev) => !prev)}
-            />
-          ) : null
-        }
-        channelType={activeChannel?.channelType}
-        visibility={activeChannel?.visibility}
-        description={channelDescription}
-        statusBadge={
-          activeChannel?.channelType === "dm" && activeDmPresenceStatus ? (
-            <PresenceBadge
-              data-testid="chat-presence-badge"
-              status={activeDmPresenceStatus}
-            />
-          ) : null
-        }
-        title={activeChannelTitle}
-      />
-
-      <div className="flex min-h-0 min-w-0 flex-1 flex-col overflow-hidden">
-        {activeChannel ? (
-          activeChannel.channelType === "forum" ? (
-            <React.Suspense
-              fallback={<ViewLoadingFallback label="Loading forum..." />}
-            >
-              <ForumView
+      <div className="relative flex min-h-0 min-w-0 flex-1 flex-col overflow-hidden">
+        <ChatHeader
+          actions={
+            activeChannel ? (
+              <ChannelMembersBar
                 channel={activeChannel}
                 currentPubkey={currentPubkey}
+                onManageChannel={onManageChannel}
+                onToggleMembers={() => setIsMembersSidebarOpen((prev) => !prev)}
               />
-            </React.Suspense>
+            ) : null
+          }
+          channelType={activeChannel?.channelType}
+          visibility={activeChannel?.visibility}
+          description={channelDescription}
+          statusBadge={
+            activeChannel?.channelType === "dm" && activeDmPresenceStatus ? (
+              <PresenceBadge
+                data-testid="chat-presence-badge"
+                status={activeDmPresenceStatus}
+              />
+            ) : null
+          }
+          title={activeChannelTitle}
+        />
+
+        <div className="relative z-0 -mt-8 flex min-h-0 min-w-0 flex-1 flex-col overflow-hidden">
+          {activeChannel ? (
+            activeChannel.channelType === "forum" ? (
+              <React.Suspense
+                fallback={<ViewLoadingFallback label="Loading forum..." />}
+              >
+                <ForumView
+                  channel={activeChannel}
+                  currentPubkey={currentPubkey}
+                />
+              </React.Suspense>
+            ) : (
+              <React.Suspense
+                fallback={<ViewLoadingFallback label="Loading channel..." />}
+              >
+                <ChannelPane
+                  activeChannel={activeChannel}
+                  currentPubkey={currentPubkey}
+                  fetchOlder={fetchOlder}
+                  hasOlderMessages={hasOlderMessages}
+                  isFetchingOlder={isFetchingOlder}
+                  editTarget={
+                    editTargetMessage
+                      ? {
+                          author: editTargetMessage.author,
+                          body: editTargetMessage.body,
+                          id: editTargetMessage.id,
+                        }
+                      : null
+                  }
+                  isSending={sendMessageMutation.isPending}
+                  isTimelineLoading={isTimelineLoading}
+                  messages={timelineMessages}
+                  onCancelEdit={handleCancelEdit}
+                  onCancelReply={handleCancelReply}
+                  onDelete={handleDelete}
+                  onEdit={handleEdit}
+                  onEditSave={handleEditSave}
+                  onReply={handleReply}
+                  onSend={handleSend}
+                  onTargetReached={onTargetReached}
+                  onToggleReaction={effectiveToggleReaction}
+                  profiles={messageProfiles}
+                  replyTargetId={replyTargetId}
+                  replyTargetMessage={replyTargetMessage}
+                  targetMessageId={
+                    activeChannel &&
+                    searchAnchor?.channelId === activeChannel.id
+                      ? searchAnchor.eventId
+                      : null
+                  }
+                  typingPubkeys={typingPubkeys}
+                />
+              </React.Suspense>
+            )
           ) : (
-            <React.Suspense
-              fallback={<ViewLoadingFallback label="Loading channel..." />}
-            >
-              <ChannelPane
-                activeChannel={activeChannel}
-                currentPubkey={currentPubkey}
-                fetchOlder={fetchOlder}
-                hasOlderMessages={hasOlderMessages}
-                isFetchingOlder={isFetchingOlder}
-                editTarget={
-                  editTargetMessage
-                    ? {
-                        author: editTargetMessage.author,
-                        body: editTargetMessage.body,
-                        id: editTargetMessage.id,
-                      }
-                    : null
-                }
-                isSending={sendMessageMutation.isPending}
-                isTimelineLoading={isTimelineLoading}
-                messages={timelineMessages}
-                onCancelEdit={handleCancelEdit}
-                onCancelReply={handleCancelReply}
-                onDelete={handleDelete}
-                onEdit={handleEdit}
-                onEditSave={handleEditSave}
-                onReply={handleReply}
-                onSend={handleSend}
-                onTargetReached={onTargetReached}
-                onToggleReaction={effectiveToggleReaction}
-                profiles={messageProfiles}
-                replyTargetId={replyTargetId}
-                replyTargetMessage={replyTargetMessage}
-                targetMessageId={
-                  activeChannel && searchAnchor?.channelId === activeChannel.id
-                    ? searchAnchor.eventId
-                    : null
-                }
-                typingPubkeys={typingPubkeys}
-              />
-            </React.Suspense>
-          )
-        ) : (
-          <div className="flex min-h-0 flex-1 items-center justify-center px-6 py-8">
-            <p className="text-sm text-muted-foreground">
-              Select a channel to view messages.
-            </p>
-          </div>
-        )}
+            <div className="flex min-h-0 flex-1 items-center justify-center px-6 py-8">
+              <p className="text-sm text-muted-foreground">
+                Select a channel to view messages.
+              </p>
+            </div>
+          )}
+        </div>
       </div>
 
       <MembersSidebar

desktop/src/features/channels/ui/MembersSidebar.tsx

@@ -147,7 +147,7 @@ export function MembersSidebar({
   return (
     <Sheet onOpenChange={onOpenChange} open={open}>
       <SheetContent
-        className="flex w-full flex-col gap-0 overflow-hidden border-l border-border/80 bg-background p-0 sm:max-w-md"
+        className="flex w-full flex-col gap-0 overflow-hidden bg-background p-0 sm:max-w-md"
         data-testid="members-sidebar"
         side="right"
       >

desktop/src/features/chat/ui/ChatHeader.tsx

@@ -60,7 +60,7 @@ export function ChatHeader({
 }: ChatHeaderProps) {
   return (
     <header
-      className="flex min-w-0 items-center gap-3 border-b border-border/80 bg-background px-4 pb-3 pt-8 sm:px-6"
+      className="relative z-20 flex shrink-0 min-w-0 items-center gap-3 bg-background/25 px-4 pb-2 pt-6 shadow-[0_4px_24px_rgba(0,0,0,0.06)] backdrop-blur-xl supports-[backdrop-filter]:bg-background/20 dark:shadow-[0_4px_24px_rgba(0,0,0,0.25)] sm:px-6"
       data-testid="chat-header"
       data-tauri-drag-region
     >

desktop/src/features/messages/lib/dateFormatters.ts

@@ -5,7 +5,7 @@
  * - `formatFullDateTime` — verbose string for tooltips
  *   ("Wednesday, April 2, 2026 at 2:34 PM").
  * - `formatDayHeading` — label for day dividers / sticky headers.
- *   Returns "Today", "Yesterday", or a date like "Monday, March 31, 2026".
+ *   Returns "Today", "Yesterday", or a compact date like "Sat, Mar 21, 2026".
  * - `isSameDay` — compare two unix-second timestamps.
  */
 
@@ -23,11 +23,12 @@ const FULL_DATE_TIME_FORMATTER = new Intl.DateTimeFormat("en-US", {
   minute: "2-digit",
 });
 
-const DAY_HEADING_FORMATTER = new Intl.DateTimeFormat("en-US", {
-  weekday: "long",
-  year: "numeric",
-  month: "long",
+/** Compact calendar line for dividers (not Today/Yesterday). */
+const DAY_HEADING_COMPACT = new Intl.DateTimeFormat("en-US", {
+  weekday: "short",
+  month: "short",
   day: "numeric",
+  year: "numeric",
 });
 
 /** Short clock time, e.g. "2:34 PM". */
@@ -42,7 +43,7 @@ export function formatFullDateTime(unixSeconds: number): string {
 
 /**
  * Human-friendly day label for dividers and sticky headers.
- * Returns "Today", "Yesterday", or a full date like "Monday, March 31, 2026".
+ * Returns "Today", "Yesterday", or a short date like "Sat, Mar 21, 2026".
  */
 export function formatDayHeading(unixSeconds: number): string {
   const date = new Date(unixSeconds * 1_000);
@@ -58,7 +59,7 @@ export function formatDayHeading(unixSeconds: number): string {
     return "Yesterday";
   }
 
-  return DAY_HEADING_FORMATTER.format(date);
+  return DAY_HEADING_COMPACT.format(date);
 }
 
 /** True when two unix-second timestamps fall on the same calendar day (local time). */

desktop/src/features/messages/ui/DayDivider.tsx

@@ -4,15 +4,15 @@ export function DayDivider({ label }: { label: string }) {
   return (
     <section
       aria-label={label}
-      className="flex items-center gap-3 py-2"
+      className="flex items-center gap-2 py-1"
       data-testid="message-timeline-day-divider"
       data-day-label={label}
     >
-      <Separator className="flex-1" />
-      <p className="text-xs font-semibold uppercase tracking-[0.22em] text-muted-foreground">
+      <Separator className="flex-1 bg-border/50" />
+      <p className="shrink-0 text-[11px] font-medium leading-none tracking-normal text-muted-foreground/70">
         {label}
       </p>
-      <Separator className="flex-1" />
+      <Separator className="flex-1 bg-border/50" />
     </section>
   );
 }

desktop/src/features/messages/ui/MessageComposer.tsx

@@ -493,10 +493,10 @@ export function MessageComposer({
   }, [media.handlePaperclip]);
 
   return (
-    <footer className="border-t border-border/80 bg-background p-4">
+    <footer className="shrink-0 bg-transparent px-4 pb-4 pt-0">
       <div className="mx-auto flex w-full max-w-4xl flex-col gap-3">
         <form
-          className="relative rounded-2xl border border-input bg-card px-3 py-4 shadow-sm sm:px-4"
+          className="relative isolate rounded-2xl border border-border/50 bg-background/25 px-3 py-4 shadow-[0_4px_24px_rgba(0,0,0,0.08)] backdrop-blur-xl supports-[backdrop-filter]:bg-background/20 dark:shadow-[0_4px_24px_rgba(0,0,0,0.35)] sm:px-4"
           data-testid="message-composer"
           onDragOver={media.handleDragOver}
           onDrop={(e) => {

desktop/src/features/messages/ui/MessageTimeline.tsx

@@ -89,25 +89,25 @@ export const MessageTimeline = React.memo(function MessageTimeline({
 
   return (
     <TooltipProvider delayDuration={200}>
-      <div className="relative min-h-0 flex-1">
+      <div className="relative flex min-h-0 min-w-0 flex-1 flex-col overflow-hidden">
         {stickyDayLabel && !isAtBottom ? (
           <div
-            className="pointer-events-none absolute inset-x-0 top-0 z-10 flex justify-center px-4 pt-2 sm:px-6"
+            className="pointer-events-none absolute inset-x-0 top-0 z-10 flex justify-center px-4 pt-1 sm:px-6"
             data-testid="message-timeline-sticky-day"
           >
-            <p className="rounded-full bg-muted/90 px-3 py-1 text-xs font-semibold uppercase tracking-[0.22em] text-muted-foreground shadow-sm backdrop-blur-sm">
+            <p className="rounded-md bg-muted/60 px-2 py-0.5 text-[11px] font-medium leading-none tracking-normal text-muted-foreground/75 shadow-sm backdrop-blur-sm">
               {stickyDayLabel}
             </p>
           </div>
         ) : null}
         <div
-          className="h-full overflow-y-auto overflow-x-hidden overscroll-contain px-4 py-3 [overflow-anchor:none] sm:px-6"
+          className="absolute inset-0 overflow-y-auto overflow-x-hidden overscroll-contain px-4 pb-3 pt-1 [overflow-anchor:none] sm:px-6"
           data-testid="message-timeline"
           onScroll={syncScrollState}
           ref={scrollContainerRef}
         >
           <div
-            className="mx-auto flex w-full max-w-4xl flex-col gap-2"
+            className="mx-auto flex w-full max-w-4xl flex-col gap-2 pb-36 pt-10"
             ref={contentRef}
           >
             <div ref={topSentinelRef} aria-hidden className="h-px" />
@@ -166,17 +166,18 @@ export const MessageTimeline = React.memo(function MessageTimeline({
         </div>
 
         {!isAtBottom ? (
-          <div className="pointer-events-none absolute inset-x-0 bottom-4 flex justify-center px-4">
+          <div className="pointer-events-none absolute inset-x-0 bottom-12 z-20 flex justify-center px-4">
             <Button
-              className="pointer-events-auto rounded-full shadow-lg"
+              className="pointer-events-auto h-7 min-h-7 gap-1.5 rounded-full border-border/50 bg-background/85 px-2.5 text-[11px] font-medium text-muted-foreground shadow-sm backdrop-blur-sm hover:bg-muted/70 hover:text-foreground [&_svg]:size-3.5"
               data-testid="message-scroll-to-latest"
               onClick={() => {
                 scrollToBottom("smooth");
               }}
               size="sm"
               type="button"
+              variant="outline"
             >
-              <ArrowDown className="h-4 w-4" />
+              <ArrowDown aria-hidden />
               {newMessageCount > 0
                 ? `${newMessageCount} new message${newMessageCount === 1 ? "" : "s"}`
                 : "Jump to latest"}

desktop/src/features/messages/ui/TypingIndicatorRow.tsx

@@ -72,7 +72,7 @@ export function TypingIndicatorRow({
   return (
     <div
       aria-live="polite"
-      className="bg-background/95 px-4 py-2 sm:px-6"
+      className="shrink-0 bg-transparent px-4 py-2 sm:px-6"
       data-testid="message-typing-indicator"
     >
       <div className="mx-auto flex w-full max-w-4xl items-center">

desktop/src/features/settings/ui/SettingsView.tsx

@@ -144,7 +144,7 @@ export function SettingsView({
         <div className="grid min-h-0 flex-1 grid-rows-[auto_minmax(0,1fr)] overflow-hidden lg:grid-cols-[220px_minmax(0,1fr)] lg:grid-rows-1">
           <aside
             className={cn(
-              "border-b border-border/70 bg-muted/20 motion-safe:transition-all motion-safe:duration-200 motion-safe:ease-out lg:border-b-0 lg:border-r",
+              "border-b border-border/70 bg-muted/20 motion-safe:transition-all motion-safe:duration-200 motion-safe:ease-out lg:border-b-0",
               isLoaded
                 ? "opacity-100 translate-x-0"
                 : "opacity-0 -translate-x-2",

desktop/src/features/workflows/ui/WorkflowDetailPanel.tsx

@@ -54,7 +54,7 @@ export function WorkflowDetailPanel({
 
   return (
     <div
-      className="flex h-full flex-col border-l bg-background"
+      className="flex h-full flex-col bg-background"
       data-testid="workflow-detail-panel"
     >
       <div className="flex items-center justify-between border-b px-4 py-3">

desktop/src/shared/ui/sheet.tsx

@@ -38,9 +38,9 @@ const sheetVariants = cva(
         top: "inset-x-0 top-0 border-b data-[state=closed]:slide-out-to-top data-[state=open]:slide-in-from-top",
         bottom:
           "inset-x-0 bottom-0 border-t data-[state=closed]:slide-out-to-bottom data-[state=open]:slide-in-from-bottom",
-        left: "inset-y-0 left-0 h-full w-3/4 border-r data-[state=closed]:slide-out-to-left data-[state=open]:slide-in-from-left sm:max-w-sm",
+        left: "inset-y-0 left-0 h-full w-3/4 data-[state=closed]:slide-out-to-left data-[state=open]:slide-in-from-left sm:max-w-sm",
         right:
-          "inset-y-0 right-0 h-full w-3/4 border-l data-[state=closed]:slide-out-to-right data-[state=open]:slide-in-from-right sm:max-w-sm",
+          "inset-y-0 right-0 h-full w-3/4 data-[state=closed]:slide-out-to-right data-[state=open]:slide-in-from-right sm:max-w-sm",
       },
     },
     defaultVariants: {

desktop/src/shared/ui/sidebar.tsx

@@ -249,7 +249,7 @@ const Sidebar = React.forwardRef<
             // Adjust the padding for floating and inset variants.
             variant === "floating" || variant === "inset"
               ? "p-2 group-data-[collapsible=icon]:w-[calc(var(--sidebar-width-icon)_+_theme(spacing.4)_+2px)]"
-              : "group-data-[collapsible=icon]:w-[--sidebar-width-icon] group-data-[side=left]:border-r group-data-[side=right]:border-l",
+              : "group-data-[collapsible=icon]:w-[--sidebar-width-icon]",
             className,
           )}
           {...props}