diff --git a/webui/src/App.tsx b/webui/src/App.tsx
index fa297681..722a6e55 100644
--- a/webui/src/App.tsx
+++ b/webui/src/App.tsx
@@ -69,6 +69,7 @@ const COMPLETED_RUNS_STORAGE_KEY = "nanobot-webui.sidebar.completed-runs.v1";
 const RESTART_STARTED_KEY = "nanobot-webui.restartStartedAt";
 const SIDEBAR_WIDTH = 272;
 const SIDEBAR_RAIL_WIDTH = 56;
+const MOBILE_SIDEBAR_WIDTH = `min(${SIDEBAR_WIDTH}px, calc(100vw - 0.75rem))`;
 const TOKEN_REFRESH_MARGIN_MS = 30_000;
 const TOKEN_REFRESH_MIN_DELAY_MS = 5_000;
 type ShellView = "chat" | "settings" | "apps" | "skills";
@@ -1498,7 +1499,7 @@ function Shell({
                 showCloseButton={false}
                 aria-describedby={undefined}
                 className="p-0 lg:hidden"
-                style={{ width: SIDEBAR_WIDTH, maxWidth: SIDEBAR_WIDTH }}
+                style={{ width: MOBILE_SIDEBAR_WIDTH, maxWidth: MOBILE_SIDEBAR_WIDTH }}
               >
                 <SheetTitle className="sr-only">{t("sidebar.navigation")}</SheetTitle>
                 <Sidebar
@@ -1604,7 +1605,7 @@ function Shell({
         {restartToast ? (
           <div
             role="status"
-            className="fixed left-1/2 top-4 z-50 -translate-x-1/2 rounded-full border border-border/70 bg-popover px-4 py-2 text-sm font-medium text-popover-foreground shadow-lg"
+            className="fixed left-1/2 top-[calc(0.75rem+env(safe-area-inset-top))] z-50 max-w-[calc(100vw-1rem)] -translate-x-1/2 rounded-full border border-border/70 bg-popover px-4 py-2 text-sm font-medium text-popover-foreground shadow-lg"
           >
             {restartToast}
           </div>
diff --git a/webui/src/components/DeleteConfirm.tsx b/webui/src/components/DeleteConfirm.tsx
index fc73edd9..d0a5ff77 100644
--- a/webui/src/components/DeleteConfirm.tsx
+++ b/webui/src/components/DeleteConfirm.tsx
@@ -80,7 +80,7 @@ export function DeleteConfirm({
             </div>
           ) : null}
         </AlertDialogHeader>
-        <AlertDialogFooter className="mt-7 grid grid-cols-2 gap-3 space-x-0">
+        <AlertDialogFooter className="mt-7 grid grid-cols-1 gap-3 space-x-0 sm:grid-cols-2">
           <AlertDialogCancel
             onClick={onCancel}
             className="mt-0 h-11 rounded-full border-0 bg-muted/70 px-5 text-[15px] font-semibold text-foreground shadow-none hover:bg-muted"
diff --git a/webui/src/components/FilePreviewPanel.tsx b/webui/src/components/FilePreviewPanel.tsx
index 2dc4fb85..9b31e6fa 100644
--- a/webui/src/components/FilePreviewPanel.tsx
+++ b/webui/src/components/FilePreviewPanel.tsx
@@ -107,7 +107,7 @@ export function FilePreviewPanel({
         "--file-preview-slot-width": !entered || isClosing ? "0px" : `${desktopWidth}px`,
       } as CSSProperties}
       className={cn(
-        "absolute inset-y-0 right-0 z-30 w-[min(92vw,var(--file-preview-slot-width))] overflow-hidden",
+        "absolute inset-y-0 right-0 z-30 w-[min(100vw,var(--file-preview-slot-width))] overflow-hidden",
         "transition-[width] duration-300 ease-out will-change-[width]",
         "md:relative md:z-auto md:w-[var(--file-preview-slot-width)] md:min-w-0 md:shrink-0",
         isClosing && "pointer-events-none",
@@ -117,7 +117,7 @@ export function FilePreviewPanel({
     >
       <div
         className={cn(
-          "absolute inset-y-0 right-0 flex w-[min(92vw,var(--file-preview-width))] flex-col overflow-hidden md:w-[var(--file-preview-width)]",
+          "absolute inset-y-0 right-0 flex w-[min(100vw,var(--file-preview-width))] flex-col overflow-hidden pb-[env(safe-area-inset-bottom)] md:w-[var(--file-preview-width)] md:pb-0",
           "border-l border-border/70 bg-background shadow-2xl md:shadow-none",
           "transition-[opacity,transform] duration-300 ease-out will-change-transform",
           !entered || isClosing ? "translate-x-full opacity-0" : "translate-x-0 opacity-100",
diff --git a/webui/src/components/settings/SettingsView.tsx b/webui/src/components/settings/SettingsView.tsx
index ad34ea80..05256e86 100644
--- a/webui/src/components/settings/SettingsView.tsx
+++ b/webui/src/components/settings/SettingsView.tsx
@@ -1566,7 +1566,7 @@ export function SettingsView({
       <main className="min-w-0 flex-1 overflow-y-auto [scrollbar-gutter:stable]">
         <div
           className={cn(
-            "mx-auto w-full max-w-[920px] px-5 py-8 sm:px-8 lg:py-12",
+            "mx-auto w-full max-w-[920px] px-4 py-6 sm:px-8 sm:py-8 lg:py-12",
             hostChromeInset && "pt-[4.25rem] sm:pt-[4.25rem] lg:pt-[4.75rem]",
           )}
         >
@@ -1652,7 +1652,7 @@ function SettingsSidebar({
   return (
     <aside
       className={cn(
-        "flex w-full shrink-0 flex-col border-b border-border/55 bg-card/62 px-4 pb-3 shadow-[inset_0_-1px_0_rgba(255,255,255,0.55)] backdrop-blur-xl dark:bg-card/45 dark:shadow-none md:w-[17rem] md:border-b-0 md:border-r md:px-3 md:pb-4 md:shadow-[inset_-1px_0_0_rgba(255,255,255,0.55)]",
+        "flex w-full shrink-0 flex-col border-b border-border/55 bg-card/62 px-3 pb-2 shadow-[inset_0_-1px_0_rgba(255,255,255,0.55)] backdrop-blur-xl dark:bg-card/45 dark:shadow-none md:w-[17rem] md:border-b-0 md:border-r md:px-3 md:pb-4 md:shadow-[inset_-1px_0_0_rgba(255,255,255,0.55)]",
         hostChromeInset ? "pt-[4.25rem] md:pt-[4.25rem]" : "pt-4 md:pt-4",
       )}
     >
@@ -5556,7 +5556,7 @@ function SettingsRow({
           </div>
         ) : null}
       </div>
-      {children ? <div className="shrink-0 sm:ml-6">{children}</div> : null}
+      {children ? <div className="min-w-0 sm:ml-6 sm:shrink-0">{children}</div> : null}
     </div>
   );
 }
@@ -5572,7 +5572,7 @@ function ReadOnlyRow({
 }) {
   return (
     <SettingsRow title={title} description={description}>
-      <span className="block max-w-[320px] truncate text-right text-[13px] text-muted-foreground">
+      <span className="block max-w-full truncate text-left text-[13px] text-muted-foreground sm:max-w-[320px] sm:text-right">
         {value}
       </span>
     </SettingsRow>
@@ -6018,7 +6018,7 @@ function NumberInput({
           const parsed = Number(event.target.value);
           if (Number.isFinite(parsed)) onChange(parsed);
         }}
-        className="h-8 w-24 rounded-full text-[13px]"
+        className="h-8 w-24 max-w-full rounded-full text-[13px]"
       />
       {suffix ? <span className="text-[12px] text-muted-foreground">{suffix}</span> : null}
     </div>
diff --git a/webui/src/components/settings/TokenUsageHeatmap.tsx b/webui/src/components/settings/TokenUsageHeatmap.tsx
index 3e5939e1..09139c91 100644
--- a/webui/src/components/settings/TokenUsageHeatmap.tsx
+++ b/webui/src/components/settings/TokenUsageHeatmap.tsx
@@ -177,7 +177,7 @@ export function TokenUsageHeatmap({
 
   return (
     <div className="overflow-x-auto pb-1 [scrollbar-width:none] [&::-webkit-scrollbar]:hidden">
-      <div className="mx-auto w-full min-w-[760px] max-w-[1054px] px-0.5">
+      <div className="mx-auto w-full min-w-0 max-w-[1054px] px-0.5 sm:min-w-[760px]">
         <div className="mb-2 flex justify-end">
           <span className="text-[11px] font-normal leading-none text-muted-foreground/64">
             {tx("settings.usage.shortTitle", "Token Usage")}
@@ -195,7 +195,7 @@ export function TokenUsageHeatmap({
           ))}
         </div>
         <div
-          className="grid grid-flow-col grid-rows-7 gap-1.5"
+          className="grid grid-flow-col grid-rows-7 gap-[3px] sm:gap-1.5"
           style={{ gridTemplateColumns: `repeat(${TOKEN_HEATMAP_COLUMNS}, minmax(0, 1fr))` }}
           aria-label={tx("settings.usage.title", "Token activity")}
         >
@@ -224,7 +224,7 @@ export function TokenUsageHeatmap({
                     <span
                       aria-label={ariaLabel}
                       className={cn(
-                        "aspect-square w-full rounded-[4px] transition-transform hover:scale-110",
+                        "aspect-square w-full rounded-[2px] transition-transform hover:scale-110 sm:rounded-[4px]",
                         tokenUsageCellClass(level, cell.future),
                       )}
                     />
diff --git a/webui/src/components/thread/ThreadComposer.tsx b/webui/src/components/thread/ThreadComposer.tsx
index 1ac6e398..fdf66345 100644
--- a/webui/src/components/thread/ThreadComposer.tsx
+++ b/webui/src/components/thread/ThreadComposer.tsx
@@ -1544,10 +1544,10 @@ export function ThreadComposer({
     "w-full resize-none bg-transparent",
     isHero
       ? cn(
-          "min-h-[78px] px-5 text-[15px] leading-6",
+          "min-h-[78px] px-4 text-[15px] leading-6 sm:px-5",
           relaxedHeroInput ? "pb-2 pt-[27px]" : "pb-1.5 pt-4",
         )
-      : "min-h-[50px] px-4 pb-1.5 pt-3 text-[13.5px] leading-5",
+      : "min-h-[50px] px-3.5 pb-1.5 pt-3 text-[13.5px] leading-5 sm:px-4",
   );
 
   return (
@@ -1699,11 +1699,13 @@ export function ThreadComposer({
         ) : null}
         <div
           className={cn(
-            "flex items-center justify-between",
-            isHero ? cn("gap-1.5 px-4", showProjectPicker ? "pb-1.5" : "pb-3.5") : "gap-2 px-3 pb-2",
+            "flex flex-wrap items-center justify-between gap-y-2",
+            isHero
+              ? cn("gap-x-1.5 px-3 sm:px-4", showProjectPicker ? "pb-1.5" : "pb-3.5")
+              : "gap-x-2 px-2.5 pb-2 sm:px-3",
           )}
         >
-          <div className={cn("flex min-w-0 flex-1 items-center", isHero ? "gap-1.5" : "gap-2")}>
+          <div className={cn("flex min-w-0 flex-1 basis-[8rem] items-center", isHero ? "gap-1.5" : "gap-2")}>
             <input
               ref={fileInputRef}
               type="file"
@@ -1746,7 +1748,7 @@ export function ThreadComposer({
               />
             ) : null}
           </div>
-          <div className={cn("flex shrink-0 items-center", isHero ? "gap-1.5" : "gap-2")}>
+          <div className={cn("ml-auto flex min-w-0 shrink-0 items-center", isHero ? "gap-1.5" : "gap-2")}>
             {modelLabel && !voiceRecorder.isRecording ? (
               <ComposerModelBadge
                 label={modelLabel}
@@ -1768,6 +1770,7 @@ export function ThreadComposer({
                       disabled={voiceRecorder.buttonDisabled}
                       aria-label={voiceButtonLabel}
                       aria-keyshortcuts={VOICE_SHORTCUT_ARIA}
+                      title={voiceButtonTooltip}
                       onPointerDown={voiceRecorder.beginPress}
                       onPointerUp={voiceRecorder.endPress}
                       onPointerCancel={voiceRecorder.endPress}
@@ -2071,7 +2074,9 @@ function ComposerModelBadge({
         "shadow-[0_2px_8px_rgba(15,23,42,0.045)]",
         interactive && "cursor-pointer hover:bg-accent/55 hover:text-foreground",
         needsSetup && "border-amber-500/35 bg-amber-50/70 text-amber-900 dark:bg-amber-500/10 dark:text-amber-200",
-        isHero ? "h-8 max-w-[12.5rem] gap-1.5 px-2 text-[11.5px]" : "h-9 max-w-[12rem] gap-2 px-2.5 text-[12px]",
+        isHero
+          ? "h-8 max-w-[min(12.5rem,44vw)] gap-1.5 px-2 text-[11.5px]"
+          : "h-9 max-w-[min(12rem,44vw)] gap-2 px-2.5 text-[12px]",
       )}
     >
       <span
@@ -2252,7 +2257,7 @@ function CliAppMentionPalette({
                 onChoose(candidate);
               }}
               className={cn(
-                "flex h-10 w-full items-center gap-2.5 rounded-[13px] px-2.5 text-left transition-colors",
+                "flex min-h-10 w-full items-center gap-2.5 rounded-[13px] px-2.5 py-1.5 text-left transition-colors",
                 selected
                   ? "bg-foreground/[0.055] text-foreground"
                   : "text-foreground/90 hover:bg-foreground/[0.04]",
@@ -2260,7 +2265,7 @@ function CliAppMentionPalette({
             >
               <MentionCandidateLogo candidate={candidate} selected={selected} />
               <span className="flex min-w-0 flex-1 items-baseline gap-2">
-                <span className="shrink-0 text-[15px] font-medium tracking-normal text-foreground">
+                <span className="min-w-0 truncate text-[15px] font-medium tracking-normal text-foreground">
                   {displayName}
                 </span>
                 <span className="truncate text-[15px] font-normal tracking-normal text-muted-foreground/72">
@@ -2396,7 +2401,7 @@ function SlashCommandPalette({
               >
                 <Icon className="h-4 w-4" />
               </span>
-              <span className="flex min-w-0 flex-1 items-baseline gap-2">
+              <span className="flex min-w-0 flex-1 flex-col gap-0.5 sm:flex-row sm:items-baseline sm:gap-2">
                 <span className="min-w-0 truncate text-[13.5px] font-semibold tracking-normal text-foreground">
                   {title}
                 </span>
@@ -2404,7 +2409,7 @@ function SlashCommandPalette({
                   {command.detail || description}
                 </span>
               </span>
-              <span className="ml-2 flex shrink-0 items-center gap-1.5">
+              <span className="ml-2 flex max-w-[42%] shrink-0 items-center gap-1.5 sm:max-w-none">
                 {command.badge || command.recent ? (
                   <span className="hidden rounded-full bg-foreground/[0.055] px-2 py-1 text-[11px] font-medium text-muted-foreground sm:inline-flex">
                     {command.badge ?? t("thread.composer.slash.badges.recent")}
@@ -2486,7 +2491,7 @@ function AttachmentChip({
         ) : null}
       </div>
       <div className="flex min-w-0 flex-col text-[11.5px] leading-4">
-        <span className="truncate max-w-[14rem] font-medium" title={image.file.name}>
+        <span className="max-w-[min(14rem,calc(100vw-8rem))] truncate font-medium" title={image.file.name}>
           {image.file.name}
         </span>
         <span className="truncate text-muted-foreground">
diff --git a/webui/src/components/thread/ThreadShell.tsx b/webui/src/components/thread/ThreadShell.tsx
index 113f660a..f9ca7be8 100644
--- a/webui/src/components/thread/ThreadShell.tsx
+++ b/webui/src/components/thread/ThreadShell.tsx
@@ -725,7 +725,7 @@ export function ThreadShell({
     </div>
   ) : (
     <div className="flex w-full flex-col items-center text-center animate-in fade-in-0 slide-in-from-bottom-2 duration-500">
-      <h1 className="text-balance text-[40px] font-normal leading-tight tracking-[-0.045em] text-foreground sm:text-[48px]">
+      <h1 className="max-w-[30rem] text-balance text-[34px] font-normal leading-[1.08] tracking-normal text-foreground sm:text-[48px] sm:leading-tight">
         {t(heroGreetingKey)}
       </h1>
     </div>
diff --git a/webui/src/components/thread/ThreadViewport.tsx b/webui/src/components/thread/ThreadViewport.tsx
index 55df4ecb..e779e1bc 100644
--- a/webui/src/components/thread/ThreadViewport.tsx
+++ b/webui/src/components/thread/ThreadViewport.tsx
@@ -335,7 +335,7 @@ export const ThreadViewport = forwardRef<ThreadViewportHandle, ThreadViewportPro
       >
         {hasMessages ? (
           <div ref={contentRef} className="mx-auto flex min-h-full w-full max-w-[64rem] flex-col">
-            <div className="flex-1 px-4 pb-20 pt-4">
+            <div className="flex-1 px-3 pb-[calc(5rem+env(safe-area-inset-bottom))] pt-4 sm:px-4">
               <div className="mx-auto w-full max-w-[49.5rem]">
                 <ThreadMessages
                   messages={visibleMessages}
@@ -355,16 +355,16 @@ export const ThreadViewport = forwardRef<ThreadViewportHandle, ThreadViewportPro
               data-testid="thread-composer-dock"
               className="sticky bottom-0 z-10 mt-auto bg-background"
             >
-              <div className="px-4 pb-3">
+              <div className="px-3 pb-[calc(0.75rem+env(safe-area-inset-bottom))] sm:px-4">
                 {composer}
               </div>
             </div>
           </div>
         ) : (
-          <div ref={contentRef} className="mx-auto flex min-h-full w-full max-w-[72rem] flex-col px-4">
-            <div className="flex w-full flex-1 items-center justify-center py-10 sm:py-12">
-              <div className="relative w-full max-w-[58rem]">
-                <div className="absolute inset-x-0 bottom-[calc(100%+1.5rem)] flex justify-center">
+          <div ref={contentRef} className="mx-auto flex min-h-full w-full max-w-[72rem] flex-col px-3 sm:px-4">
+            <div className="flex w-full flex-1 items-center justify-center py-6 sm:py-12">
+              <div className="relative flex w-full max-w-[58rem] flex-col items-center gap-5 sm:block">
+                <div className="flex justify-center sm:absolute sm:inset-x-0 sm:bottom-[calc(100%+1.5rem)]">
                   {emptyState}
                 </div>
                 <div className="w-full">{composer}</div>
diff --git a/webui/src/components/thread/WorkspaceControls.tsx b/webui/src/components/thread/WorkspaceControls.tsx
index 8c80ac24..7fef4755 100644
--- a/webui/src/components/thread/WorkspaceControls.tsx
+++ b/webui/src/components/thread/WorkspaceControls.tsx
@@ -106,7 +106,7 @@ export function WorkspaceProjectPicker({
 
   if (nativeProjectPicker) {
     return (
-      <div className="flex items-center rounded-b-[28px] border-t border-border/25 bg-muted/60 px-4 py-1.5 dark:bg-white/[0.055]">
+      <div className="flex min-w-0 items-center rounded-b-[28px] border-t border-border/25 bg-muted/60 px-3 py-1.5 dark:bg-white/[0.055] sm:px-4">
         <button
           type="button"
           disabled={disabled || pickingFolder}
@@ -114,7 +114,7 @@ export function WorkspaceProjectPicker({
           title={currentProjectScope?.project_path}
           onClick={() => void pickNativeFolder()}
           className={cn(
-            "inline-flex h-7 max-w-[18rem] items-center gap-2 rounded-full px-2.5",
+            "inline-flex h-7 max-w-full items-center gap-2 rounded-full px-2.5 sm:max-w-[18rem]",
             "text-[12px] font-medium text-muted-foreground/90 transition-colors",
             "hover:bg-background/70 hover:text-foreground disabled:pointer-events-none disabled:opacity-55",
             currentProjectScope && "text-foreground/82",
@@ -124,7 +124,7 @@ export function WorkspaceProjectPicker({
           <span className="truncate">{projectLabel}</span>
         </button>
         {pathError || error ? (
-          <span role="alert" className="ml-2 truncate text-[11.5px] font-medium text-destructive">
+          <span role="alert" className="ml-2 min-w-0 truncate text-[11.5px] font-medium text-destructive">
             {pathError ?? error}
           </span>
         ) : null}
@@ -133,7 +133,7 @@ export function WorkspaceProjectPicker({
   }
 
   return (
-    <div className="flex items-center rounded-b-[28px] border-t border-border/25 bg-muted/60 px-4 py-1.5 dark:bg-white/[0.055]">
+    <div className="flex min-w-0 items-center rounded-b-[28px] border-t border-border/25 bg-muted/60 px-3 py-1.5 dark:bg-white/[0.055] sm:px-4">
       <DropdownMenu open={open} onOpenChange={setOpen}>
         <DropdownMenuTrigger asChild>
           <button
@@ -141,7 +141,7 @@ export function WorkspaceProjectPicker({
             disabled={disabled}
             aria-label={t("thread.composer.workspace.projectAria")}
             className={cn(
-              "inline-flex h-7 max-w-[18rem] items-center gap-2 rounded-full px-2.5",
+              "inline-flex h-7 max-w-full items-center gap-2 rounded-full px-2.5 sm:max-w-[18rem]",
               "text-[12px] font-medium text-muted-foreground/90 transition-colors",
               "hover:bg-background/70 hover:text-foreground disabled:pointer-events-none disabled:opacity-55",
               currentProjectScope && "text-foreground/82",
@@ -254,7 +254,7 @@ export function WorkspaceAccessMenu({
           variant="ghost"
           aria-label={t("thread.composer.workspace.accessAria")}
           className={cn(
-            "max-w-[12.5rem] rounded-[10px] border border-transparent font-semibold shadow-none",
+            "max-w-[min(12.5rem,42vw)] rounded-[10px] border border-transparent font-semibold shadow-none",
             isHero ? "h-8 px-2.5 text-[12px]" : "h-9 px-3 text-[12.5px]",
             isFull
               ? "bg-transparent text-orange-600 hover:bg-orange-500/8 dark:text-orange-300 dark:hover:bg-orange-400/10"