No rounded corners

ios/Packages/Sybil/Sources/Sybil/SybilAPIClient.swift

@@ -74,6 +74,16 @@ actor SybilAPIClient: SybilAPIClienting {
         return response.chat
     }
 
+    func forkChat(chatID: String, messageID: String? = nil) async throws -> ChatSummary {
+        let response = try await request(
+            "/v1/chats/\(chatID)/fork",
+            method: "POST",
+            body: AnyEncodable(ChatForkBody(messageId: messageID)),
+            responseType: ChatCreateResponse.self
+        )
+        return response.chat
+    }
+
     func updateChatTitle(chatID: String, title: String) async throws -> ChatSummary {
         let response = try await request(
             "/v1/chats/\(chatID)",
@@ -704,6 +714,10 @@ private struct ChatTitleUpdateBody: Encodable {
     var title: String
 }
 
+private struct ChatForkBody: Encodable {
+    var messageId: String?
+}
+
 private struct StarUpdateBody: Encodable {
     var starred: Bool
 }

ios/Packages/Sybil/Sources/Sybil/SybilAPIClienting.swift

@@ -11,6 +11,7 @@ protocol SybilAPIClienting: Sendable {
         messages: [CompletionRequestMessage]?
     ) async throws -> ChatSummary
     func getChat(chatID: String) async throws -> ChatDetail
+    func forkChat(chatID: String, messageID: String?) async throws -> ChatSummary
     func updateChatTitle(chatID: String, title: String) async throws -> ChatSummary
     func updateChatStar(chatID: String, starred: Bool) async throws -> ChatSummary
     func deleteChat(chatID: String) async throws

ios/Packages/Sybil/Sources/Sybil/SybilChatTranscriptView.swift

@@ -1,5 +1,6 @@
 import MarkdownUI
 import SwiftUI
+import UIKit
 
 struct SybilChatTranscriptView: View {
     var messages: [Message]
@@ -9,6 +10,8 @@ struct SybilChatTranscriptView: View {
     var topContentInset: CGFloat = 0
     var bottomContentInset: CGFloat = 0
     var bottomPinRequestID: Int = 0
+    var isForking: Bool = false
+    var onForkResponse: ((String) -> Void)? = nil
 
     @State private var hasTrackedToolCallMessages = false
     @State private var knownToolCallMessageIDs: Set<String> = []
@@ -45,7 +48,11 @@ struct SybilChatTranscriptView: View {
                             MessageBubble(
                                 message: message,
                                 isSending: isSending,
-                                streamingAssistantPresentation: streamingAssistantPresentation
+                                streamingAssistantPresentation: streamingAssistantPresentation,
+                                isForking: isForking,
+                                onFork: {
+                                    onForkResponse?(message.id)
+                                }
                             )
                                 .frame(maxWidth: .infinity)
                         case let .toolGroup(id, messages):
@@ -146,6 +153,8 @@ private struct MessageBubble: View {
     var message: Message
     var isSending: Bool
     var streamingAssistantPresentation: StreamingAssistantPresentation?
+    var isForking: Bool
+    var onFork: (() -> Void)?
 
     private var toolCallMetadata: ToolCallMetadata? {
         message.toolCallMetadata
@@ -164,7 +173,37 @@ private struct MessageBubble: View {
         return streamingAssistantPresentation
     }
 
+    private var canFork: Bool {
+        message.role == .assistant &&
+            !message.id.hasPrefix("temp-") &&
+            onFork != nil
+    }
+
     var body: some View {
+        Group {
+            if canFork {
+                bubbleContent
+                    .contextMenu {
+                        Button {
+                            UIPasteboard.general.string = message.content
+                        } label: {
+                            Label("Copy", systemImage: "doc.on.doc")
+                        }
+
+                        Button {
+                            onFork?()
+                        } label: {
+                            Label("Fork", systemImage: "arrow.triangle.branch")
+                        }
+                        .disabled(isForking)
+                    }
+            } else {
+                bubbleContent
+            }
+        }
+    }
+
+    private var bubbleContent: some View {
         HStack(alignment: .top, spacing: 0) {
             leadingSpacer
 

ios/Packages/Sybil/Sources/Sybil/SybilPhoneShellView.swift

@@ -130,7 +130,10 @@ struct SybilPhoneShellView: View {
             route: route,
             onRequestBack: { _ in showSidebarOverlay() },
             onRequestNewChat: sidebarWorkspaceNewChatAction,
-            onShowSidebar: showSidebarOverlay
+            onShowSidebar: showSidebarOverlay,
+            onOpenForkedChat: { chatID in
+                showRoute(.chat(chatID))
+            }
         )
         .background(SybilTheme.background)
         .blur(radius: SidebarOverlaySwipeMetrics.workspaceBlurRadius(for: sidebarOverlayProgress))
@@ -511,6 +514,9 @@ private struct SybilPhoneSidebarRoot: View {
                 },
                 onSelect: { item in
                     onSelect(item.selection)
+                },
+                onOpenForkedChat: { chatID in
+                    onSelect(.chat(chatID))
                 }
             )
         }
@@ -585,6 +591,7 @@ private struct SybilPhoneDestinationView: View {
     let onRequestBack: (_ animateNavigation: Bool) -> Void
     let onRequestNewChat: (() -> Void)?
     let onShowSidebar: () -> Void
+    let onOpenForkedChat: (String) -> Void
 
     var body: some View {
         SybilWorkspaceView(
@@ -593,7 +600,8 @@ private struct SybilPhoneDestinationView: View {
             navigationLeadingControl: .showSidebar,
             onShowSidebar: onShowSidebar,
             onRequestBack: onRequestBack,
-            onRequestNewChat: onRequestNewChat
+            onRequestNewChat: onRequestNewChat,
+            onOpenForkedChat: onOpenForkedChat
         )
         .frame(maxWidth: .infinity, maxHeight: .infinity, alignment: .topLeading)
         .task(id: route) {

ios/Packages/Sybil/Sources/Sybil/SybilQuickQuestionView.swift

@@ -102,13 +102,12 @@ struct SybilQuickQuestionView: View {
                         set: { viewModel.updateQuickQuestionPrompt($0) }
                     ),
                     selection: $promptSelection,
-                    axis: .vertical
+                    axis: .horizontal
                 )
                 .focused($promptFocused)
                 .font(.body)
                 .textInputAutocapitalization(.sentences)
                 .autocorrectionDisabled(false)
-                .lineLimit(1 ... 6)
                 .submitLabel(.send)
                 .onSubmit(submitQuestion)
                 .padding(.horizontal, 12)

ios/Packages/Sybil/Sources/Sybil/SybilSidebarView.swift

@@ -1,5 +1,6 @@
 import Observation
 import SwiftUI
+import UIKit
 
 struct SybilSidebarView: View {
     @Bindable var viewModel: SybilViewModel
@@ -111,6 +112,7 @@ struct SybilSidebarItemList: View {
     @Bindable var viewModel: SybilViewModel
     var isSelected: (SidebarItem) -> Bool
     var onSelect: (SidebarItem) -> Void
+    var onOpenForkedChat: ((String) -> Void)? = nil
     @State private var renameTarget: SidebarItem?
     @State private var renameTitle = ""
 
@@ -168,13 +170,26 @@ struct SybilSidebarItemList: View {
                                     Label(item.starred ? "Unstar" : "Star", systemImage: item.starred ? "star.slash" : "star")
                                 }
 
-                                if item.kind == .chat {
+                                if case let .chat(chatID) = item.selection {
+                                    Button {
+                                        forkChat(item)
+                                    } label: {
+                                        Label("Fork", systemImage: "arrow.triangle.branch")
+                                    }
+                                    .disabled(viewModel.isForkingChat || item.isRunning)
+
                                     Button {
                                         renameTarget = item
                                         renameTitle = item.title
                                     } label: {
                                         Label("Rename", systemImage: "pencil")
                                     }
+
+                                    Button {
+                                        UIPasteboard.general.string = chatID
+                                    } label: {
+                                        Label("Copy Session ID", systemImage: "doc.on.doc")
+                                    }
                                 }
 
                                 Button(role: .destructive) {
@@ -215,6 +230,28 @@ struct SybilSidebarItemList: View {
             .disabled(renameTitle.trimmingCharacters(in: .whitespacesAndNewlines).isEmpty)
         }
     }
+
+    private func forkChat(_ item: SidebarItem) {
+        guard case let .chat(chatID) = item.selection else {
+            return
+        }
+
+        let selectionAtStart = viewModel.selectedItem
+        let draftKindAtStart = viewModel.draftKind
+        Task {
+            guard let forkedChat = await viewModel.forkChat(chatID: chatID),
+                  viewModel.selectedItem == selectionAtStart,
+                  viewModel.draftKind == draftKindAtStart else {
+                return
+            }
+
+            if let onOpenForkedChat {
+                onOpenForkedChat(forkedChat.id)
+            } else {
+                viewModel.select(.chat(forkedChat.id))
+            }
+        }
+    }
 }
 
 struct SybilSidebarRow: View {

ios/Packages/Sybil/Sources/Sybil/SybilViewModel.swift

@@ -170,6 +170,7 @@ final class SybilViewModel {
     var isLoadingCollections = false
     var isLoadingSelection = false
     var isCreatingSearchChat = false
+    var isForkingChat = false
     var chatBottomPinRequestID = 0
     var errorMessage: String?
 
@@ -958,6 +959,36 @@ final class SybilViewModel {
         }
     }
 
+    @discardableResult
+    func forkChat(chatID: String, messageID: String? = nil) async -> ChatSummary? {
+        guard isAuthenticated, !isForkingChat else {
+            return nil
+        }
+
+        guard messageID != nil || !isChatRowRunning(chatID) else {
+            errorMessage = "Wait for the response to finish before forking this chat."
+            return nil
+        }
+
+        let forkDescription = messageID.map { "chat \(chatID) from response \($0)" } ?? "chat \(chatID)"
+        SybilLog.info(SybilLog.ui, "Forking \(forkDescription)")
+        errorMessage = nil
+        isForkingChat = true
+        defer {
+            isForkingChat = false
+        }
+
+        do {
+            let forkedChat = try await client().forkChat(chatID: chatID, messageID: messageID)
+            applyChatSummary(forkedChat, moveToFront: true)
+            return forkedChat
+        } catch {
+            errorMessage = normalizeAPIError(error)
+            SybilLog.error(SybilLog.ui, "Fork failed", error: error)
+            return nil
+        }
+    }
+
     func renameChat(chatID: String, title: String) async {
         guard isAuthenticated else {
             return

ios/Packages/Sybil/Sources/Sybil/SybilWorkspaceView.swift

@@ -19,6 +19,7 @@ struct SybilWorkspaceView: View {
     var onShowSidebar: (() -> Void)? = nil
     var onRequestBack: ((_ animateNavigation: Bool) -> Void)? = nil
     var onRequestNewChat: (() -> Void)? = nil
+    var onOpenForkedChat: ((String) -> Void)? = nil
     @FocusState private var composerFocused: Bool
     @Environment(\.dismiss) private var dismiss
     @State private var isShowingAttachmentOptions = false
@@ -196,7 +197,9 @@ struct SybilWorkspaceView: View {
                         streamingAssistantPresentation: viewModel.displayedStreamingAssistantPresentation,
                         topContentInset: showsCustomWorkspaceNavigation ? customWorkspaceNavigationContentInset : 0,
                         bottomContentInset: viewModel.showsComposer ? composerOverlayContentInset : 0,
-                        bottomPinRequestID: viewModel.chatBottomPinRequestID
+                        bottomPinRequestID: viewModel.chatBottomPinRequestID,
+                        isForking: viewModel.isForkingChat,
+                        onForkResponse: forkResponse
                     )
                     .id(transcriptScrollContextID)
                 }
@@ -230,6 +233,28 @@ struct SybilWorkspaceView: View {
         }
     }
 
+    private func forkResponse(messageID: String) {
+        guard viewModel.draftKind == nil,
+              case let .chat(chatID) = viewModel.selectedItem else {
+            return
+        }
+
+        let selectionAtStart = viewModel.selectedItem
+        Task {
+            guard let forkedChat = await viewModel.forkChat(chatID: chatID, messageID: messageID),
+                  viewModel.selectedItem == selectionAtStart,
+                  viewModel.draftKind == nil else {
+                return
+            }
+
+            if let onOpenForkedChat {
+                onOpenForkedChat(forkedChat.id)
+            } else {
+                viewModel.select(.chat(forkedChat.id))
+            }
+        }
+    }
+
     private var customWorkspaceNavigationBar: some View {
         HStack(spacing: 14) {
             workspaceNavigationLeadingControl

ios/Packages/Sybil/Tests/SybilTests/SybilTests.swift

@@ -13,6 +13,9 @@ private struct MockClientCallSnapshot: Sendable {
     var listSearches = 0
     var createChat = 0
     var getChat = 0
+    var forkChat = 0
+    var lastForkChatID: String?
+    var lastForkMessageID: String?
     var updateChatTitle = 0
     var suggestChatTitle = 0
     var updateChatStar = 0
@@ -43,6 +46,7 @@ private actor MockSybilClient: SybilAPIClienting {
     private let chatDetails: [String: ChatDetail]
     private let searchDetails: [String: SearchDetail]
     private let createChatResponse: ChatSummary?
+    private let forkChatResponse: ChatSummary?
     private let updateChatTitleResponses: [String: ChatSummary]
     private let suggestChatTitleResponses: [String: ChatSummary]
     private let updateChatStarResponses: [String: ChatSummary]
@@ -74,6 +78,7 @@ private actor MockSybilClient: SybilAPIClienting {
         chatDetails: [String: ChatDetail] = [:],
         searchDetails: [String: SearchDetail] = [:],
         createChatResponse: ChatSummary? = nil,
+        forkChatResponse: ChatSummary? = nil,
         updateChatTitleResponses: [String: ChatSummary] = [:],
         suggestChatTitleResponses: [String: ChatSummary] = [:],
         updateChatStarResponses: [String: ChatSummary] = [:],
@@ -87,6 +92,7 @@ private actor MockSybilClient: SybilAPIClienting {
         self.chatDetails = chatDetails
         self.searchDetails = searchDetails
         self.createChatResponse = createChatResponse
+        self.forkChatResponse = forkChatResponse
         self.updateChatTitleResponses = updateChatTitleResponses
         self.suggestChatTitleResponses = suggestChatTitleResponses
         self.updateChatStarResponses = updateChatStarResponses
@@ -220,6 +226,16 @@ private actor MockSybilClient: SybilAPIClienting {
         return detail
     }
 
+    func forkChat(chatID: String, messageID: String?) async throws -> ChatSummary {
+        snapshot.forkChat += 1
+        snapshot.lastForkChatID = chatID
+        snapshot.lastForkMessageID = messageID
+        guard let forkChatResponse else {
+            throw UnexpectedClientCall()
+        }
+        return forkChatResponse
+    }
+
     func updateChatTitle(chatID: String, title: String) async throws -> ChatSummary {
         snapshot.updateChatTitle += 1
         guard let summary = updateChatTitleResponses[chatID] else {
@@ -775,6 +791,63 @@ private func makeCompletionToolCall(
     #expect(viewModel.errorMessage == nil)
 }
 
+@MainActor
+@Test func wholeChatForkAddsReturnedChatToWorkspace() async throws {
+    let date = Date(timeIntervalSince1970: 1_700_000_160)
+    let source = makeChatSummary(id: "chat-source", date: date)
+    var forked = makeChatSummary(id: "chat-fork", date: date.addingTimeInterval(10))
+    forked.title = "Fork of Chat chat-source"
+    forked.parentChatId = source.id
+    forked.titleGenerationPending = true
+    let client = MockSybilClient(forkChatResponse: forked)
+    let viewModel = SybilViewModel(settings: testSettings(named: #function)) { _ in client }
+    viewModel.isAuthenticated = true
+    viewModel.isCheckingSession = false
+    viewModel.chats = [source]
+    viewModel.workspaceItems = [WorkspaceItem(chat: source)]
+    viewModel.selectedItem = .chat(source.id)
+
+    let result = await viewModel.forkChat(chatID: source.id)
+
+    let snapshot = await client.currentSnapshot()
+    #expect(snapshot.forkChat == 1)
+    #expect(snapshot.lastForkChatID == source.id)
+    #expect(snapshot.lastForkMessageID == nil)
+    #expect(result == forked)
+    #expect(viewModel.chats.first == forked)
+    #expect(viewModel.workspaceItems.first == WorkspaceItem(chat: forked))
+    #expect(viewModel.selectedItem == .chat(source.id))
+    #expect(!viewModel.isForkingChat)
+    #expect(viewModel.errorMessage == nil)
+}
+
+@MainActor
+@Test func responseForkPassesAssistantMessageID() async throws {
+    let date = Date(timeIntervalSince1970: 1_700_000_165)
+    let source = makeChatSummary(id: "chat-source", date: date)
+    var forked = makeChatSummary(id: "response-fork", date: date.addingTimeInterval(10))
+    forked.title = "Fork of 'A useful response'"
+    forked.parentChatId = source.id
+    forked.titleGenerationPending = true
+    let client = MockSybilClient(forkChatResponse: forked)
+    let viewModel = SybilViewModel(settings: testSettings(named: #function)) { _ in client }
+    viewModel.isAuthenticated = true
+    viewModel.isCheckingSession = false
+    viewModel.chats = [source]
+    viewModel.workspaceItems = [WorkspaceItem(chat: source)]
+
+    let result = await viewModel.forkChat(chatID: source.id, messageID: "assistant-message")
+
+    let snapshot = await client.currentSnapshot()
+    #expect(snapshot.forkChat == 1)
+    #expect(snapshot.lastForkChatID == source.id)
+    #expect(snapshot.lastForkMessageID == "assistant-message")
+    #expect(result == forked)
+    #expect(viewModel.sidebarItems.contains(where: { $0.selection == .chat(forked.id) }))
+    #expect(!viewModel.isForkingChat)
+    #expect(viewModel.errorMessage == nil)
+}
+
 @MainActor
 @Test func starringItemsUpdatesSidebarState() async throws {
     let date = Date(timeIntervalSince1970: 1_700_000_175)

ios/README.md

@@ -17,7 +17,9 @@ Hiding the panel preserves the draft and answer and lets an in-flight answer fin
 **Open in Chat** saves the question and answer in the regular workspace.
 
 The regular Mac chat/search composer uses the same Return/Shift+Return rules.
-Holding Return does not repeatedly submit. The iOS software keyboard is unchanged.
+Holding Return does not repeatedly submit. On iOS, Return submits from Quick
+Question, while the normal chat/search composer continues to use Return for a
+new line.
 
 Closing the last Mac window leaves Sybil running, so Option+Space still works.
 Use **Sybil → Quit Sybil** or **Command+Q** to quit the application. The Catalyst
@@ -66,7 +68,9 @@ action, and does not build or embed the macOS helper.
   answer remain available. Reopen the workspace from the panel, then explicitly
   quit with Command+Q. Rebuild and relaunch after changing lifecycle plist keys.
 - In both Mac and iOS Quick Question, reopen an existing prompt and type to replace
-  it. In the Mac workspace, verify Return submits and Shift+Return adds a newline.
+  it. On iOS, verify Return submits Quick Question while Return in the normal
+  prompt adds a newline. In the Mac workspace, verify Return submits and
+  Shift+Return adds a newline.
 - Check Command+N both with a workspace open and after closing every workspace.
   Command+Shift+N must open another window even when one already exists, and
   Command+Option+N must start a search without opening a window.

web/src/App.tsx

@@ -1,4 +1,4 @@
-import { useEffect, useMemo, useRef, useState } from "preact/hooks";
+import { useEffect, useLayoutEffect, useMemo, useRef, useState } from "preact/hooks";
 import type { TargetedTouchEvent } from "preact";
 import {
   Check,
@@ -654,9 +654,10 @@ type ModelComboboxProps = {
   value: string;
   onChange: (value: string) => void;
   disabled?: boolean;
+  className?: string;
 };
 
-function ModelCombobox({ options, value, onChange, disabled = false }: ModelComboboxProps) {
+function ModelCombobox({ options, value, onChange, disabled = false, className }: ModelComboboxProps) {
   const [open, setOpen] = useState(false);
   const [draftValue, setDraftValue] = useState(value);
   const rootRef = useRef<HTMLDivElement>(null);
@@ -710,7 +711,12 @@ function ModelCombobox({ options, value, onChange, disabled = false }: ModelComb
 
   return (
     <div className="relative" ref={rootRef}>
-      <div className="flex h-10 min-w-56 items-center rounded-lg border border-violet-300/22 bg-background/72 px-3 text-sm shadow-[inset_0_1px_0_hsl(255_100%_92%_/_0.06)]">
+      <div
+        className={cn(
+          "flex h-10 min-w-56 items-center rounded-lg border border-violet-300/22 bg-background/72 px-3 text-sm shadow-[inset_0_1px_0_hsl(255_100%_92%_/_0.06)]",
+          className
+        )}
+      >
         <input
           ref={inputRef}
           value={draftValue}
@@ -948,7 +954,6 @@ export default function App() {
     isCheckingSession,
     isSigningIn,
     isAuthenticated,
-    authMode,
     authError,
     handleAuthFailure: baseHandleAuthFailure,
     handleSignIn,
@@ -1018,6 +1023,7 @@ export default function App() {
   const transcriptEndRef = useRef<HTMLDivElement>(null);
   const contextMenuRef = useRef<HTMLDivElement>(null);
   const renameChatInputRef = useRef<HTMLInputElement>(null);
+  const chatSettingsDialogRef = useRef<HTMLDialogElement>(null);
   const fileInputRef = useRef<HTMLInputElement>(null);
   const dragDepthRef = useRef(0);
   const pendingAttachmentsRef = useRef<ChatAttachment[]>([]);
@@ -1930,6 +1936,7 @@ export default function App() {
     if (!isAuthenticated) return;
 
     const handleKeyDown = (event: KeyboardEvent) => {
+      if (chatSettingsDialogRef.current?.open) return;
       const hasPrimaryModifier = event.metaKey || event.ctrlKey;
       if (!hasPrimaryModifier || event.altKey) return;
 
@@ -2331,16 +2338,16 @@ export default function App() {
     return () => window.clearTimeout(timer);
   }, [renameChatDialog]);
 
-  useEffect(() => {
+  useLayoutEffect(() => {
     if (!isChatSettingsOpen) return;
-    const handleKeyDown = (event: KeyboardEvent) => {
-      if (event.key !== "Escape" || isSavingChatSettings) return;
-      event.preventDefault();
-      setIsChatSettingsOpen(false);
+    const dialog = chatSettingsDialogRef.current;
+    const previouslyFocused = document.activeElement;
+    dialog?.showModal();
+    return () => {
+      dialog?.close();
+      if (previouslyFocused instanceof HTMLElement) previouslyFocused.focus({ preventScroll: true });
     };
-    window.addEventListener("keydown", handleKeyDown);
-    return () => window.removeEventListener("keydown", handleKeyDown);
-  }, [isChatSettingsOpen, isSavingChatSettings]);
+  }, [isChatSettingsOpen]);
 
   useEffect(() => {
     if (!isQuickQuestionOpen) return;
@@ -3433,7 +3440,7 @@ export default function App() {
 
   return (
     <div className="app-grid-surface app-safe-frame h-full">
-      <div className="workspace-shell flex h-full w-full overflow-hidden bg-transparent md:gap-2">
+      <div className="workspace-shell flex h-full w-full overflow-hidden bg-transparent">
         {isMobileSidebarOpen ? (
           <button
             type="button"
@@ -3445,19 +3452,13 @@ export default function App() {
 
         <aside
           className={cn(
-            "workspace-sidebar glass-panel fixed inset-y-0 left-0 z-40 flex w-[86vw] max-w-80 shrink-0 flex-col border-r border-violet-300/18 transition-transform md:static md:z-auto md:w-80 md:max-w-none md:rounded-2xl md:border",
+            "workspace-sidebar glass-panel fixed inset-y-0 left-0 z-40 flex w-[86vw] max-w-80 shrink-0 flex-col border-r border-violet-300/18 transition-transform md:static md:z-auto md:w-80 md:max-w-none",
             isMobileSidebarOpen ? "translate-x-0" : "-translate-x-full md:translate-x-0"
           )}
         >
-          <div className="relative min-h-24 px-4 pb-4 pt-5">
-            <div className="pr-24">
-              <div className="sybil-wordmark bg-[linear-gradient(90deg,#ff8df8,#9a6dff_54%,#67dfff)] bg-clip-text text-3xl text-transparent">
-                SYBIL
-              </div>
-              <p className="mt-2 flex items-center gap-1.5 text-xs font-medium text-muted-foreground">
-                <span className="h-1.5 w-1.5 rounded-full bg-emerald-400" />
-                Sybil Web{authMode ? ` (${authMode === "open" ? "open mode" : "token mode"})` : ""}
-              </p>
+          <div className="relative min-h-24 px-4 pb-4 pt-5 flex items-center">
+            <div className="sybil-wordmark bg-[linear-gradient(90deg,#ff8df8,#9a6dff_54%,#67dfff)] bg-clip-text text-3xl text-transparent">
+              SYBIL
             </div>
             <SybilCharacter
               className="absolute right-4 top-3 h-[calc(100%-1.5rem)]"
@@ -3608,7 +3609,7 @@ export default function App() {
         </aside>
 
         <main
-          className="workspace-content glass-panel relative flex min-w-0 flex-1 touch-pan-y flex-col overflow-hidden border-violet-300/18 md:touch-auto md:rounded-2xl md:border"
+          className="workspace-content glass-panel relative flex min-w-0 flex-1 touch-pan-y flex-col overflow-hidden md:touch-auto"
           onTouchStart={handleMobileWorkspaceTouchStart}
           onTouchMove={handleMobileWorkspaceTouchMove}
           onTouchEnd={handleMobileWorkspaceTouchEnd}
@@ -3822,44 +3823,66 @@ export default function App() {
         </div>
       ) : null}
       {isChatSettingsOpen ? (
-        <div
-          className="fixed inset-0 z-[60] flex items-center justify-center bg-black/72 p-3 backdrop-blur-md md:p-6"
+        <dialog
+          ref={chatSettingsDialogRef}
+          aria-labelledby="chat-settings-title"
+          className="fixed inset-0 m-0 flex h-dvh max-h-none w-full max-w-none items-center justify-center overflow-hidden bg-transparent p-0 text-foreground backdrop:bg-black/70 backdrop:backdrop-blur-md md:p-6"
+          onCancel={(event) => {
+            event.preventDefault();
+            if (!isSavingChatSettings) setIsChatSettingsOpen(false);
+          }}
           onMouseDown={(event) => {
             if (event.target === event.currentTarget && !isSavingChatSettings) setIsChatSettingsOpen(false);
           }}
         >
           <form
-            role="dialog"
-            aria-modal="true"
-            aria-labelledby="chat-settings-title"
-            className="glass-panel flex max-h-[88vh] w-full max-w-2xl flex-col rounded-2xl border border-violet-300/24 p-4 shadow-2xl shadow-black/45 md:p-5"
+            className="glass-panel flex h-full min-h-0 w-full flex-col overflow-hidden md:h-auto md:max-h-full md:max-w-2xl md:rounded-2xl md:border md:border-violet-300/24"
             onSubmit={(event) => void handleChatSettingsSubmit(event)}
           >
-            <div className="mb-4 flex items-center justify-between gap-3">
+            <div className="chat-settings-header grid shrink-0 grid-cols-[minmax(0,1fr)_auto_minmax(0,1fr)] items-center gap-2 border-b border-violet-300/16 md:flex md:justify-between md:gap-3">
+              <Button
+                type="button"
+                variant="ghost"
+                className="h-11 justify-self-start px-2 text-violet-200 hover:bg-violet-400/10 hover:text-violet-100 md:hidden"
+                onClick={() => setIsChatSettingsOpen(false)}
+                disabled={isSavingChatSettings}
+              >
+                Cancel
+              </Button>
               <div className="min-w-0">
-                <h2 id="chat-settings-title" className="text-sm font-semibold text-violet-50">
+                <h2 id="chat-settings-title" className="text-base font-semibold text-violet-50 md:text-sm">
                   Chat settings
                 </h2>
-                <p className="mt-1 truncate text-xs text-muted-foreground">{chatSettingsTitleDraft.trim() || "New chat"}</p>
+                <p className="mt-1 hidden truncate text-xs text-muted-foreground md:block">{chatSettingsTitleDraft.trim() || "New chat"}</p>
               </div>
               <Button
                 type="button"
                 size="icon"
                 variant="ghost"
-                className="h-8 w-8"
+                className="hidden h-8 w-8 shrink-0 md:inline-flex"
                 onClick={() => setIsChatSettingsOpen(false)}
                 disabled={isSavingChatSettings}
                 aria-label="Close chat settings"
               >
                 <X className="h-4 w-4" />
               </Button>
+              <Button
+                type="submit"
+                variant="ghost"
+                className="h-11 justify-self-end gap-1.5 px-2 font-semibold text-violet-200 hover:bg-violet-400/10 hover:text-violet-100 md:hidden"
+                disabled={isSavingChatSettings}
+              >
+                {isSavingChatSettings ? <LoaderCircle className="h-4 w-4 animate-spin" /> : null}
+                Save
+              </Button>
             </div>
 
-            <div className="min-h-0 flex-1 space-y-4 overflow-y-auto pr-1">
+            <div className="chat-settings-content min-h-0 flex-1 space-y-5 overflow-y-auto overscroll-contain md:space-y-4">
               <div>
-                <span className="mb-1.5 block text-xs font-semibold text-violet-100/72">Chat title</span>
+                <label for="chat-settings-chat-title" className="mb-1.5 block text-xs font-semibold text-violet-100/72">Chat title</label>
                 <div className="flex items-center gap-2">
                   <input
+                    id="chat-settings-chat-title"
                     value={chatSettingsTitleDraft}
                     onInput={(event) => {
                       setChatSettingsTitleDraft(event.currentTarget.value);
@@ -3867,7 +3890,7 @@ export default function App() {
                     }}
                     maxLength={120}
                     placeholder={draftKind === null && selectedItem?.kind === "chat" ? "Chat title" : "Optional title"}
-                    className="h-11 min-w-0 flex-1 rounded-lg border border-violet-300/22 bg-background/72 px-3 text-sm text-violet-50 outline-none shadow-[inset_0_1px_0_hsl(255_100%_92%_/_0.06)] placeholder:text-muted-foreground focus:border-violet-300/45 focus:ring-1 focus:ring-ring/70"
+                    className="h-11 min-w-0 flex-1 rounded-lg border border-violet-300/22 bg-background/70 px-3 text-base text-violet-50 outline-none shadow-[inset_0_1px_0_hsl(255_100%_92%_/_0.06)] placeholder:text-muted-foreground focus:border-violet-300/45 focus:ring-1 focus:ring-ring/70 md:text-sm"
                     disabled={isSavingChatSettings}
                   />
                   {chatSettingsChatId ? (
@@ -3895,7 +3918,7 @@ export default function App() {
                 <label className="block">
                   <span className="mb-1.5 block text-xs font-semibold text-violet-100/72">Provider</span>
                   <select
-                    className="h-10 w-full rounded-lg border border-violet-300/22 bg-background/72 px-3 text-sm text-violet-50 outline-none shadow-[inset_0_1px_0_hsl(255_100%_92%_/_0.06)] focus:border-violet-300/45 focus:ring-1 focus:ring-ring/70"
+                    className="h-11 w-full rounded-lg border border-violet-300/22 bg-background/70 px-3 text-base text-violet-50 outline-none shadow-[inset_0_1px_0_hsl(255_100%_92%_/_0.06)] focus:border-violet-300/45 focus:ring-1 focus:ring-ring/70 md:h-10 md:text-sm"
                     value={chatSettingsProviderDraft}
                     onChange={(event) => {
                       const nextProvider = event.currentTarget.value as Provider;
@@ -3917,6 +3940,7 @@ export default function App() {
                 <label className="block min-w-0">
                   <span className="mb-1.5 block text-xs font-semibold text-violet-100/72">Model</span>
                   <ModelCombobox
+                    className="h-11 min-w-0 bg-background/70 text-base md:h-10 md:text-sm"
                     options={chatSettingsProviderModelOptions}
                     value={chatSettingsModelDraft}
                     disabled={isSavingChatSettings}
@@ -3938,7 +3962,7 @@ export default function App() {
                     if (chatSettingsError) setChatSettingsError(null);
                   }}
                   placeholder="Add per-chat instructions"
-                  className="min-h-32 resize-y border-violet-300/24 bg-background/72 text-sm text-violet-50 placeholder:text-violet-200/45"
+                  className="min-h-32 resize-y border-violet-300/24 bg-background/70 text-base text-violet-50 placeholder:text-violet-200/45 md:text-sm"
                   disabled={isSavingChatSettings}
                 />
               </label>
@@ -3952,6 +3976,7 @@ export default function App() {
                         type="button"
                         size="sm"
                         variant="secondary"
+                        className="h-11 gap-1.5 md:h-8"
                         onClick={() => setChatSettingsEnabledToolsDraft(getDefaultEnabledTools(availableChatTools))}
                         disabled={isSavingChatSettings}
                       >
@@ -3962,6 +3987,7 @@ export default function App() {
                         type="button"
                         size="sm"
                         variant="secondary"
+                        className="h-11 gap-1.5 md:h-8"
                         onClick={() => setChatSettingsEnabledToolsDraft([])}
                         disabled={isSavingChatSettings}
                       >
@@ -3971,31 +3997,30 @@ export default function App() {
                     </div>
                   ) : null}
                 </div>
-                <div className="space-y-2">
+                <div className="grid gap-2 md:grid-cols-2">
                   {availableChatTools.length ? (
                     availableChatTools.map((tool) => {
                       const checked = chatSettingsEnabledToolsDraft.includes(tool.name);
                       return (
                         <label
                           key={tool.name}
-                          className="flex cursor-pointer items-start gap-3 rounded-lg border border-violet-300/18 bg-background/44 px-3 py-2.5 transition hover:border-violet-300/34 hover:bg-violet-400/8"
+                          title={tool.description}
+                          className="flex min-h-11 min-w-0 cursor-pointer items-center gap-3 rounded-lg border border-violet-300/18 bg-background/44 px-3 py-2.5 transition hover:border-violet-300/34 hover:bg-violet-400/8 focus-within:border-violet-300/45 focus-within:ring-1 focus-within:ring-ring/70"
                         >
                           <input
                             type="checkbox"
                             checked={checked}
                             onChange={() => toggleChatSettingsTool(tool.name)}
-                            className="mt-1 h-4 w-4 rounded border-violet-300/35 bg-background/80 accent-violet-400"
+                            className="h-4 w-4 shrink-0 rounded border-violet-300/35 bg-background/80 accent-violet-400"
+                            aria-description={tool.description}
                             disabled={isSavingChatSettings}
                           />
-                          <span className="min-w-0">
-                            <span className="block text-sm font-medium text-violet-50">{getToolLabel(tool.name)}</span>
-                            <span className="mt-0.5 block text-xs leading-5 text-muted-foreground">{tool.description}</span>
-                          </span>
+                          <span className="min-w-0 break-words text-sm font-medium text-violet-50">{getToolLabel(tool.name)}</span>
                         </label>
                       );
                     })
                   ) : (
-                    <p className="rounded-lg border border-violet-300/18 bg-background/44 px-3 py-2.5 text-sm text-muted-foreground">
+                    <p className="rounded-lg border border-violet-300/18 bg-background/44 px-3 py-2.5 text-sm text-muted-foreground md:col-span-2">
                       No chat tools are available.
                     </p>
                   )}
@@ -4003,8 +4028,8 @@ export default function App() {
               </section>
             </div>
 
-            {chatSettingsError ? <p className="mt-3 text-sm text-rose-300">{chatSettingsError}</p> : null}
-            <div className="mt-4 flex justify-end gap-2">
+            {chatSettingsError ? <p role="alert" className="chat-settings-error shrink-0 break-words border-t border-violet-300/16 text-sm text-rose-300">{chatSettingsError}</p> : null}
+            <div className="hidden shrink-0 justify-end gap-2 border-t border-violet-300/16 p-5 md:flex">
               <Button type="button" variant="secondary" onClick={() => setIsChatSettingsOpen(false)} disabled={isSavingChatSettings}>
                 Cancel
               </Button>
@@ -4014,7 +4039,7 @@ export default function App() {
               </Button>
             </div>
           </form>
-        </div>
+        </dialog>
       ) : null}
       {renameChatDialog ? (
         <div
@@ -4073,7 +4098,7 @@ export default function App() {
       ) : null}
       {isQuickQuestionOpen ? (
         <div
-          className="fixed inset-0 z-[60] flex items-center justify-center bg-black/72 p-3 backdrop-blur-md md:p-6"
+          className="fixed inset-0 z-[60] flex items-center justify-center bg-black/40 p-3 md:p-6"
           onMouseDown={(event) => {
             if (event.target === event.currentTarget) setIsQuickQuestionOpen(false);
           }}

web/src/components/chat/chat-messages-panel.tsx

@@ -378,13 +378,13 @@ function ToolCallStack({
           );
         })}
         {!expanded && hiddenCount ? (
-          <span className="absolute bottom-1 right-10 z-20 rounded-full border border-cyan-300/30 bg-slate-950/86 px-2 py-0.5 text-[10px] font-semibold leading-none text-cyan-100 shadow-sm">
+          <span className="absolute bottom-1 right-10 z-20 rounded-none border border-cyan-300/30 bg-slate-950/86 px-2 py-0.5 text-[10px] font-semibold leading-none text-cyan-100 shadow-sm">
             +{hiddenCount}
           </span>
         ) : null}
         <button
           type="button"
-          className="tool-call-stack-toggle absolute right-0 top-2 z-20 flex h-8 w-8 items-center justify-center rounded-full"
+          className="tool-call-stack-toggle absolute right-0 top-2 z-20 flex h-8 w-8 items-center justify-center rounded-none"
           aria-expanded={expanded ? "true" : "false"}
           aria-label={`${expanded ? "Collapse" : "Expand"} ${countLabel}`}
           title={`${expanded ? "Collapse" : "Expand"} ${countLabel}`}
@@ -603,7 +603,7 @@ export function ChatMessagesPanel({ messages, isLoading, isSending, onMessageCon
                 className={cn(
                   "max-w-[85%] space-y-3",
                   isUser
-                    ? "rounded-xl border border-violet-300/24 bg-[linear-gradient(135deg,hsl(258_86%_48%_/_0.86),hsl(278_72%_29%_/_0.86))] px-4 py-3 text-sm leading-6 text-fuchsia-50 shadow-sm"
+                    ? "chat-user-message border border-violet-300/24 bg-[linear-gradient(135deg,hsl(258_86%_48%_/_0.86),hsl(278_72%_29%_/_0.86))] px-4 py-3 text-sm leading-6 text-fuchsia-50 shadow-sm"
                     : "text-base leading-7 text-violet-50"
                 )}
                 onContextMenu={

web/src/index.css

@@ -31,7 +31,7 @@
   --secondary-foreground: 254 38% 94%;
   --accent: 188 86% 50%;
   --accent-foreground: 230 45% 8%;
-  --radius: 0.5rem;
+  --radius: 0px;
 }
 
 * {
@@ -72,6 +72,7 @@ select,
 textarea {
   font: inherit;
   color-scheme: dark;
+  border-radius: var(--radius);
 }
 
 ::selection {
@@ -113,13 +114,39 @@ textarea {
     max(0.75rem, var(--safe-area-left));
 }
 
+.chat-settings-header {
+  padding:
+    calc(0.5rem + var(--safe-area-top))
+    max(0.75rem, var(--safe-area-right))
+    0.5rem
+    max(0.75rem, var(--safe-area-left));
+}
+
+.chat-settings-content {
+  padding:
+    1rem
+    max(1rem, var(--safe-area-right))
+    max(1.5rem, var(--safe-area-bottom))
+    max(1rem, var(--safe-area-left));
+  scroll-padding-block: 1rem;
+}
+
+.chat-settings-error {
+  padding:
+    0.75rem
+    max(1rem, var(--safe-area-right))
+    max(0.75rem, var(--safe-area-bottom))
+    max(1rem, var(--safe-area-left));
+}
+
 @media (min-width: 768px) {
-  .app-safe-frame {
-    padding:
-      max(0.5rem, var(--safe-area-top))
-      max(0.5rem, var(--safe-area-right))
-      max(0.5rem, var(--safe-area-bottom))
-      max(0.5rem, var(--safe-area-left));
+  .chat-settings-header,
+  .chat-settings-content {
+    padding: 1.25rem;
+  }
+
+  .chat-settings-error {
+    padding: 0.75rem 1.25rem;
   }
 
   .app-search-safe-pad {
@@ -132,19 +159,11 @@ textarea {
 }
 
 @media (horizontal-viewport-segments: 2) {
-  .app-safe-frame {
-    padding:
-      max(0.5rem, var(--safe-area-top))
-      max(0.5rem, var(--safe-area-right))
-      max(0.5rem, var(--safe-area-bottom))
-      max(0.5rem, var(--safe-area-left));
-  }
-
   .workspace-shell {
     display: grid;
     grid-template-columns:
-      calc(env(viewport-segment-width 0 0) - max(0.5rem, var(--safe-area-left)))
-      calc(env(viewport-segment-width 1 0) - max(0.5rem, var(--safe-area-right)));
+      calc(env(viewport-segment-width 0 0) - var(--safe-area-left))
+      calc(env(viewport-segment-width 1 0) - var(--safe-area-right));
     column-gap: calc(env(viewport-segment-left 1 0) - env(viewport-segment-right 0 0));
   }
 
@@ -153,14 +172,10 @@ textarea {
     width: 100%;
     max-width: none;
     transform: none;
-    border-width: 1px;
-    border-radius: 1rem;
   }
 
   .workspace-content {
     min-width: 0;
-    border-width: 1px;
-    border-radius: 1rem;
     touch-action: auto;
   }
 
@@ -179,6 +194,13 @@ textarea {
     0 14px 36px hsl(240 80% 2% / 0.28);
 }
 
+.chat-user-message {
+  /* Preserve the original bubble radius independently of the square UI theme.
+     Browsers without corner-shape support fall back to circular corners. */
+  border-radius: 0.75rem;
+  corner-shape: squircle;
+}
+
 .tool-call-stack-shell {
   perspective: 900px;
   transform-style: preserve-3d;
@@ -430,7 +452,7 @@ textarea {
   overflow-x: auto;
   overflow-y: hidden;
   border: 1px solid hsl(var(--border) / 0.86);
-  border-radius: 0.625rem;
+  border-radius: var(--radius);
   background: hsl(246 34% 10% / 0.76);
   box-shadow: inset 0 1px 0 hsl(258 80% 88% / 0.06);
 }
@@ -449,7 +471,7 @@ textarea {
 }
 
 .md-table-scroll::-webkit-scrollbar-thumb {
-  border-radius: 9999px;
+  border-radius: var(--radius);
   background: hsl(263 78% 72% / 0.34);
 }
 
@@ -561,7 +583,7 @@ textarea {
 
 .md-content code {
   background: hsl(249 40% 10% / 0.78);
-  border-radius: 0.3rem;
+  border-radius: var(--radius);
   padding: 0.05rem 0.3rem;
   font-size: 0.86em;
   box-decoration-break: clone;
@@ -571,7 +593,7 @@ textarea {
 .md-content pre {
   overflow-x: auto;
   border: 1px solid hsl(253 31% 29% / 0.72);
-  border-radius: 0.625rem;
+  border-radius: var(--radius);
   background: hsl(249 40% 10% / 0.82);
   padding: 0.75rem;
   box-shadow: inset 0 1px 0 hsl(258 80% 88% / 0.05);
@@ -595,7 +617,7 @@ textarea {
 .md-cite-token {
   display: inline-flex;
   align-items: center;
-  border-radius: 9999px;
+  border-radius: var(--radius);
   border: 1px solid hsl(274 40% 55%);
   background: hsl(277 33% 21%);
   color: hsl(304 42% 96%);

web/tailwind.config.ts

@@ -29,9 +29,14 @@ const config: Config = {
         },
       },
       borderRadius: {
+        // Keep surfaces square at every size; rounded-full is reserved for dots.
+        DEFAULT: "var(--radius)",
+        sm: "var(--radius)",
+        md: "var(--radius)",
         lg: "var(--radius)",
-        md: "calc(var(--radius) - 2px)",
-        sm: "calc(var(--radius) - 4px)",
+        xl: "var(--radius)",
+        "2xl": "var(--radius)",
+        "3xl": "var(--radius)",
       },
     },
   },