refactor(header): improve mobile header layout with responsive action controls

src/app/page.tsx

@@ -15,7 +15,6 @@ import { DragDropContainer } from "@/components/drag-drop-container";
 import { EventDialog } from "@/components/event-dialog";
 import { EventsList } from "@/components/events-list";
 import { IcsFilePicker } from "@/components/ics-file-picker";
-import { ModeToggle } from "@/components/mode-toggle";
 import { SettingsPanel } from "@/components/settings-panel";
 import SignIn from "@/components/sign-in";
 import { Badge } from "@/components/ui/badge";
@@ -432,12 +431,21 @@ export default function HomePage() {
 		isMobile ? "px-4 pb-24 pt-4" : "px-8 py-4",
 	);
 	const appHeaderSurfaceClasses = getAppHeaderSurfaceClasses(isMobile);
+	const headerLayoutClasses = cn(
+		isMobile ? "flex-col items-start" : "items-center justify-between",
+	);
 	const appSectionSurfaceClasses = getAppSectionSurfaceClasses(isMobile);
 	const appNavSurfaceClasses = getAppNavSurfaceClasses(isMobile);
 	const mainContentClasses = cn(
 		"grid items-start gap-4",
 		isMobile ? "grid-cols-1" : "grid-cols-[minmax(0,0.75fr)_minmax(0,1.25fr)]",
 	);
+	const headerActionsClasses = isMobile
+		? "flex w-full items-center justify-between gap-2"
+		: "flex flex-wrap items-center justify-end gap-2";
+	const mobileUtilityActionsClasses = "flex items-center gap-2";
+	const desktopUtilityActionsClasses = "flex items-center gap-2";
+	const moreTriggerLabel = isMobile ? null : "More";
 
 	return (
 		<DragDropContainer
@@ -447,8 +455,13 @@ export default function HomePage() {
 			onImageDrop={(file) => handleImagesSelect([file])}
 		>
 			<div className={appFrameClasses}>
-				<header className={appHeaderSurfaceClasses}>
-					<div className="flex min-w-0 flex-col">
+				<header className={cn(appHeaderSurfaceClasses, headerLayoutClasses)}>
+					<div
+						className={cn(
+							"flex min-w-0 flex-col",
+							isMobile ? "w-full" : undefined,
+						)}
+					>
 						<p className="font-mono text-[11px] uppercase text-muted-foreground">
 							Local Calendar
 						</p>
@@ -456,7 +469,7 @@ export default function HomePage() {
 							Event timeline
 						</h1>
 					</div>
-					<div className="flex flex-wrap items-center justify-end gap-2">
+					<div className={headerActionsClasses}>
 						<Badge
 							variant="outline"
 							className={getConnectionBadgeClasses(isOnline)}
@@ -468,41 +481,63 @@ export default function HomePage() {
 							)}
 							<span>{isOnline ? "Online ready" : "Offline mode"}</span>
 						</Badge>
-						<SignIn />
-						<ModeToggle />
-						<Button
-							type="button"
-							variant="outline"
-							size="sm"
-							onClick={handleExport}
-							disabled={events.length === 0}
+						<div
+							className={
+								isMobile
+									? mobileUtilityActionsClasses
+									: desktopUtilityActionsClasses
+							}
 						>
-							Export
-						</Button>
-						<DropdownMenu>
-							<DropdownMenuTrigger asChild>
-								<Button type="button" variant="outline" size="sm">
-									<MoreHorizontal className="h-4 w-4" />
-									More
-								</Button>
-							</DropdownMenuTrigger>
-							<DropdownMenuContent align="end" className="w-48">
-								<DropdownMenuItem onClick={openManualEventDialog}>
-									Manual create
-								</DropdownMenuItem>
-								<DropdownMenuItem onClick={() => setActiveView("settings")}>
-									Settings
-								</DropdownMenuItem>
-								<DropdownMenuSeparator />
-								<DropdownMenuItem
-									variant="destructive"
-									onClick={handleClearAll}
+							<SignIn />
+							{!isMobile && (
+								<Button
+									type="button"
+									variant="outline"
+									size="sm"
+									onClick={handleExport}
 									disabled={events.length === 0}
 								>
-									Clear all events
-								</DropdownMenuItem>
-							</DropdownMenuContent>
-						</DropdownMenu>
+									Export
+								</Button>
+							)}
+							<DropdownMenu>
+								<DropdownMenuTrigger asChild>
+									<Button
+										type="button"
+										variant="outline"
+										size={isMobile ? "icon" : "sm"}
+										aria-label="More actions"
+									>
+										<MoreHorizontal className="h-4 w-4" />
+										{moreTriggerLabel}
+									</Button>
+								</DropdownMenuTrigger>
+								<DropdownMenuContent align="end" className="w-48">
+									{isMobile && (
+										<DropdownMenuItem
+											onClick={handleExport}
+											disabled={events.length === 0}
+										>
+											Export
+										</DropdownMenuItem>
+									)}
+									<DropdownMenuItem onClick={openManualEventDialog}>
+										Manual create
+									</DropdownMenuItem>
+									<DropdownMenuItem onClick={() => setActiveView("settings")}>
+										Settings
+									</DropdownMenuItem>
+									<DropdownMenuSeparator />
+									<DropdownMenuItem
+										variant="destructive"
+										onClick={handleClearAll}
+										disabled={events.length === 0}
+									>
+										Clear all events
+									</DropdownMenuItem>
+								</DropdownMenuContent>
+							</DropdownMenu>
+						</div>
 					</div>
 				</header>