Feature: Smooth sidebar animation, fixed theme button clipping, moved import to profile menu, added custom webapp context menu, and polished TickTick style detail panel

src/app/globals.css

@@ -62,8 +62,8 @@
   --dur-slow: 300ms;
 
   /* Layout */
-  --sidebar-width: 240px;
+  --sidebar-width: 260px;
-  --detail-width: min(560px, 48vw);
+  --detail-width: min(580px, 50vw);
   --header-height: 56px;
 }
 
@@ -1680,8 +1680,81 @@ a { color: inherit; text-decoration: none; }
   display: none;
 }
 
-@media (max-width: 768px) {
+/* ============================================
-  .mobile-only {
+   CUSTOM CONTEXT MENU
+   ============================================ */
+.custom-context-menu {
+  background: var(--bg-primary);
+  border: 1px solid var(--border);
+  border-radius: var(--radius-md);
+  box-shadow: var(--shadow-lg);
+  padding: 5px;
+  min-width: 170px;
+  animation: dropdownIn var(--dur-fast) var(--ease-out);
+  backdrop-filter: blur(12px);
+  user-select: none;
+}
+
+.context-menu-item {
   display: flex;
+  align-items: center;
+  gap: 8px;
+  padding: 7px 10px;
+  font-size: 13px;
+  font-weight: 500;
+  color: var(--text-primary);
+  border-radius: var(--radius-xs);
+  cursor: pointer;
+  transition: background var(--dur-fast), color var(--dur-fast);
 }
+
+.context-menu-item:hover {
+  background: var(--bg-hover);
+  color: var(--accent);
+}
+
+.context-menu-item.danger {
+  color: var(--danger);
+}
+
+.context-menu-item.danger:hover {
+  background: rgba(239, 68, 68, 0.1);
+  color: var(--danger);
+}
+
+.context-menu-divider {
+  height: 1px;
+  background: var(--border);
+  margin: 4px 0;
+}
+
+.context-menu-icon {
+  font-size: 14px;
+  width: 16px;
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  opacity: 0.8;
+}
+
+/* TickTick Style Meta Chip */
+.tick-meta-chip {
+  display: inline-flex;
+  align-items: center;
+  gap: 5px;
+  padding: 4px 10px;
+  border-radius: var(--radius-full);
+  background: var(--bg-secondary);
+  border: 1px solid var(--border);
+  color: var(--text-secondary);
+  font-size: 12px;
+  font-weight: 500;
+  cursor: pointer;
+  transition: all var(--dur-fast);
+}
+
+.tick-meta-chip:hover {
+  background: var(--bg-hover);
+  color: var(--text-primary);
+  border-color: var(--border-medium);
 }

src/components/layout/AppShell.tsx

@@ -1,4 +1,4 @@
-"use client";
+"use client";
 import { useState, useCallback, useEffect } from "react";
 import { Sidebar } from "./Sidebar";
 import { TaskList, Task, List, User } from "../tasks/TaskList";
@@ -361,6 +361,7 @@ export function AppShell({ user, isDemo = false }: AppShellProps) {
             refresh();
           }}
           listId={selectedTask.listId}
+          listName={lists.find((l) => l.id === selectedTask.listId)?.name}
           isDemo={isDemo}
           onDemoUpdateTask={handleDemoUpdateTask}
           onDemoDeleteTask={handleDemoDeleteTask}

src/components/layout/Sidebar.tsx

@@ -1,9 +1,10 @@
-"use client";
+"use client";
-import { useState, useEffect, useRef } from "react";
+import React, { useState, useEffect, useRef } from "react";
 import { signOut } from "next-auth/react";
-import { useI18n, Language } from "@/lib/i18n";
+import { useI18n } from "@/lib/i18n";
-import { useTheme, ThemeMode } from "@/app/providers";
+import { useTheme } from "@/app/providers";
 import { LanguageSelector } from "@/components/ui/LanguageSelector";
+import { ContextMenu, MenuItem } from "@/components/ui/ContextMenu";
 
 interface User { id: string; name?: string | null; email?: string | null }
 interface List { id: string; name: string; color: string; icon: string; _count?: { tasks: number } }
@@ -35,8 +36,8 @@ export function Sidebar({
   onDemoCreateList,
   onDemoDeleteList,
 }: SidebarProps) {
-  const { t, lang, setLang } = useI18n();
+  const { t } = useI18n();
-  const { theme, setTheme, toggleTheme } = useTheme();
+  const { theme, toggleTheme } = useTheme();
 
   const [showNewList, setShowNewList] = useState(false);
   const [newListName, setNewListName] = useState("");
@@ -47,6 +48,9 @@ export function Sidebar({
   const [importing, setImporting] = useState(false);
   const [importResult, setImportResult] = useState("");
 
+  // Context Menu for Lists
+  const [contextMenu, setContextMenu] = useState<{ x: number; y: number; listId: string } | null>(null);
+
   const inputRef = useRef<HTMLInputElement>(null);
   const fileRef = useRef<HTMLInputElement>(null);
 
@@ -156,13 +160,25 @@ export function Sidebar({
 
   const initials = user.name?.split(" ").map((n) => n[0]).join("").toUpperCase().slice(0, 2) || "?";
 
+  // List context menu items
+  const getListContextMenuItems = (listId: string): MenuItem[] => [
+    {
+      label: t("deleteListConfirm").split("?")[0],
+      icon: "🗑️",
+      danger: true,
+      onClick: () => deleteList(listId),
+    },
+  ];
+
   return (
     <aside className={`sidebar${mobileOpen ? " mobile-open" : ""}`}>
-      {/* Header */}
+      {/* Header with Logo & Controls */}
-      <div className="sidebar-header">
+      <div className="sidebar-header" style={{ padding: "14px 14px 10px", gap: 8 }}>
         <div className="sidebar-logo">✓</div>
-        <div style={{ display: "flex", flexDirection: "column" }}>
+        <div style={{ display: "flex", flexDirection: "column", minWidth: 0, flex: 1 }}>
-          <span className="sidebar-title">{t("appName")}</span>
+          <span className="sidebar-title" style={{ whiteSpace: "nowrap", overflow: "hidden", textOverflow: "ellipsis" }}>
+            {t("appName")}
+          </span>
           {isDemo && (
             <span style={{ fontSize: 10, color: "var(--accent)", fontWeight: 700, letterSpacing: 0.3 }}>
               {t("demoBadge")}
@@ -170,9 +186,8 @@ export function Sidebar({
           )}
         </div>
 
-        {/* Top Quick Actions (Lang & Theme) */}
+        {/* Top Controls: Language & Theme — Fixed without clipping */}
-        <div style={{ marginLeft: "auto", display: "flex", alignItems: "center", gap: 6 }}>
+        <div style={{ display: "flex", alignItems: "center", gap: 4, flexShrink: 0 }}>
-          {/* Custom Language Selector Popover */}
           <LanguageSelector />
 
           {/* Theme 3-Way Toggle Button */}
@@ -181,20 +196,21 @@ export function Sidebar({
             id="theme-toggle"
             onClick={toggleTheme}
             title={`${t("theme")}: ${theme === "system" ? t("themeSystem") : theme === "light" ? t("themeLight") : t("themeDark")}`}
-            style={{ width: 28, height: 28 }}
+            style={{ width: 28, height: 28, flexShrink: 0 }}
+            type="button"
           >
             {theme === "system" ? (
-              <svg width="15" height="15" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2">
+              <svg width="14" height="14" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2">
                 <rect x="2" y="3" width="20" height="14" rx="2" ry="2" />
                 <line x1="8" y1="21" x2="16" y2="21" />
                 <line x1="12" y1="17" x2="12" y2="21" />
               </svg>
             ) : theme === "light" ? (
-              <svg width="15" height="15" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2">
+              <svg width="14" height="14" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2">
                 <circle cx="12" cy="12" r="5" /><line x1="12" y1="1" x2="12" y2="3" /><line x1="12" y1="21" x2="12" y2="23" /><line x1="4.22" y1="4.22" x2="5.64" y2="5.64" /><line x1="18.36" y1="18.36" x2="19.78" y2="19.78" /><line x1="1" y1="12" x2="3" y2="12" /><line x1="21" y1="12" x2="23" y2="12" /><line x1="4.22" y1="19.78" x2="5.64" y2="18.36" /><line x1="18.36" y1="5.64" x2="19.78" y2="4.22" />
               </svg>
             ) : (
-              <svg width="15" height="15" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2">
+              <svg width="14" height="14" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2">
                 <path d="M21 12.79A9 9 0 1 1 11.21 3 7 7 0 0 0 21 12.79z" />
               </svg>
             )}
@@ -202,7 +218,7 @@ export function Sidebar({
         </div>
       </div>
 
-      {/* Nav */}
+      {/* Nav List */}
       <nav className="sidebar-nav">
         <div className="sidebar-section">
           <div className="sidebar-section-label">{t("lists")}</div>
@@ -211,6 +227,10 @@ export function Sidebar({
               key={list.id}
               className={`sidebar-item${selectedListId === list.id ? " active" : ""}`}
               onClick={() => onListSelect(list.id)}
+              onContextMenu={(e) => {
+                e.preventDefault();
+                setContextMenu({ x: e.clientX, y: e.clientY, listId: list.id });
+              }}
               id={`list-item-${list.id}`}
             >
               <div className="list-dot" style={{ background: list.color }} />
@@ -218,14 +238,15 @@ export function Sidebar({
               <span className="item-count">{list._count?.tasks || ""}</span>
               <button
                 className="icon-btn"
-                style={{ width: 22, height: 22, opacity: 0.5 }}
+                style={{ width: 22, height: 22, opacity: 0.4 }}
                 onClick={(e) => {
                   e.stopPropagation();
                   deleteList(list.id);
                 }}
                 title="Delete list"
+                type="button"
               >
-                <svg width="12" height="12" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2">
+                <svg width="11" height="11" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2">
                   <polyline points="3 6 5 6 21 6" /><path d="M19 6l-1 14H6L5 6" /><path d="M10 11v6M14 11v6" /><path d="M9 6V4h6v2" />
                 </svg>
               </button>
@@ -233,9 +254,9 @@ export function Sidebar({
           ))}
         </div>
 
-        {/* New list */}
+        {/* New list form */}
         {showNewList ? (
-          <div style={{ padding: "4px 8px" }}>
+          <div style={{ padding: "4px 10px" }}>
             <div style={{ display: "flex", flexWrap: "wrap", gap: 6, padding: "6px 4px 8px" }}>
               {LIST_COLORS.map((c) => (
                 <div
@@ -259,30 +280,25 @@ export function Sidebar({
               style={{ marginBottom: 6 }}
             />
             <div style={{ display: "flex", gap: 6 }}>
-              <button className="btn btn-primary btn-sm" style={{ flex: 1 }} onClick={createList}>{t("create")}</button>
+              <button className="btn btn-primary btn-sm" style={{ flex: 1 }} onClick={createList} type="button">
-              <button className="btn btn-ghost btn-sm" onClick={() => setShowNewList(false)}>{t("cancel")}</button>
+                {t("create")}
+              </button>
+              <button className="btn btn-ghost btn-sm" onClick={() => setShowNewList(false)} type="button">
+                {t("cancel")}
+              </button>
             </div>
           </div>
         ) : (
-          <button id="new-list-btn" className="sidebar-add-btn" onClick={() => setShowNewList(true)}>
+          <button id="new-list-btn" className="sidebar-add-btn" onClick={() => setShowNewList(true)} type="button">
             <svg width="14" height="14" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2.5">
               <line x1="12" y1="5" x2="12" y2="19" /><line x1="5" y1="12" x2="19" y2="12" />
             </svg>
             {t("newList")}
           </button>
         )}
-
-        <div className="sidebar-section" style={{ borderTop: "1px solid var(--border)", paddingTop: 12, marginTop: 4 }}>
-          <button id="import-btn" className="sidebar-add-btn" onClick={() => { setShowImport(true); setImportListId(lists[0]?.id || ""); }}>
-            <svg width="14" height="14" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2">
-              <path d="M21 15v4a2 2 0 0 1-2 2H5a2 2 0 0 1-2-2v-4" /><polyline points="17 8 12 3 7 8" /><line x1="12" y1="3" x2="12" y2="15" />
-            </svg>
-            {t("importTasks")}
-          </button>
-        </div>
       </nav>
 
-      {/* User footer */}
+      {/* User footer with Profile Menu containing Import */}
       <div className="sidebar-footer">
         <div className="user-card" id="user-menu-btn" onClick={() => setUserMenuOpen((p) => !p)} style={{ position: "relative" }}>
           <div className="user-avatar" style={{ background: "#4B7BF5" }}>{initials}</div>
@@ -290,8 +306,32 @@ export function Sidebar({
             <div className="user-name">{user.name || (isDemo ? "Demo User" : "User")}</div>
             <div className="user-email">{user.email || (isDemo ? "demo@checkflow.local" : "")}</div>
           </div>
+          <svg width="14" height="14" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2" style={{ opacity: 0.5 }}>
+            <polyline points="6 9 12 15 18 9" />
+          </svg>
+
+          {/* User Popover Menu */}
           {userMenuOpen && (
-            <div className="dropdown" style={{ bottom: "100%", left: 0, right: 0, marginBottom: 4 }}>
+            <div className="dropdown" style={{ bottom: "calc(100% + 6px)", left: 0, right: 0, marginBottom: 0 }}>
+              {/* Import Action */}
+              <div
+                className="dropdown-item"
+                id="sidebar-import-menu-item"
+                onClick={(e) => {
+                  e.stopPropagation();
+                  setShowImport(true);
+                  setImportListId(lists[0]?.id || "");
+                  setUserMenuOpen(false);
+                }}
+              >
+                <svg width="14" height="14" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2">
+                  <path d="M21 15v4a2 2 0 0 1-2 2H5a2 2 0 0 1-2-2v-4" /><polyline points="17 8 12 3 7 8" /><line x1="12" y1="3" x2="12" y2="15" />
+                </svg>
+                {t("importTasks")}
+              </div>
+
+              <div className="context-menu-divider" />
+
               {isDemo ? (
                 <div
                   className="dropdown-item"
@@ -315,6 +355,16 @@ export function Sidebar({
         </div>
       </div>
 
+      {/* Context Menu on List */}
+      {contextMenu && (
+        <ContextMenu
+          x={contextMenu.x}
+          y={contextMenu.y}
+          items={getListContextMenuItems(contextMenu.listId)}
+          onClose={() => setContextMenu(null)}
+        />
+      )}
+
       {/* Import modal */}
       {showImport && (
         <div className="modal-overlay" onClick={() => setShowImport(false)}>
@@ -339,8 +389,8 @@ export function Sidebar({
               </p>
             )}
             <div className="modal-footer">
-              <button className="btn btn-ghost" onClick={() => setShowImport(false)}>{t("cancel")}</button>
+              <button className="btn btn-ghost" onClick={() => setShowImport(false)} type="button">{t("cancel")}</button>
-              <button id="import-submit-btn" className="btn btn-primary" onClick={handleImport} disabled={importing}>
+              <button id="import-submit-btn" className="btn btn-primary" onClick={handleImport} disabled={importing} type="button">
                 {importing ? t("importing") : t("importBtn")}
               </button>
             </div>

src/components/tasks/TaskDetail.tsx

@@ -1,4 +1,4 @@
-"use client";
+"use client";
 import React, { useState, useEffect, useCallback, useRef } from "react";
 import { useI18n } from "@/lib/i18n";
 import { Task } from "./TaskList";
@@ -7,6 +7,7 @@ import { MarkdownNoteEditor } from "./MarkdownNoteEditor";
 interface Props {
   task: Task;
   listId: string;
+  listName?: string;
   onClose: () => void;
   onUpdate: (t: Task) => void;
   onDelete: () => void;
@@ -18,6 +19,7 @@ interface Props {
 export function TaskDetail({
   task,
   listId,
+  listName,
   onClose,
   onUpdate,
   onDelete,
@@ -488,8 +490,13 @@ export function TaskDetail({
           )}
         </div>
 
-        {/* Footer Timestamp */}
+        {/* Footer Info: Project Badge & Timestamp */}
-        <div style={{ fontSize: 11, color: "var(--text-tertiary)", display: "flex", justifyContent: "space-between" }}>
+        <div style={{ fontSize: 11, color: "var(--text-tertiary)", display: "flex", justifyContent: "space-between", alignItems: "center", borderTop: "1px solid var(--border)", paddingTop: 8 }}>
+          {listName && (
+            <span className="tick-meta-chip" style={{ fontSize: 11, padding: "2px 8px" }}>
+              📁 {listName}
+            </span>
+          )}
           <span>
             {t("created")}:{" "}
             {new Date(task.createdAt).toLocaleDateString(lang === "ko" ? "ko-KR" : lang === "ja" ? "ja-JP" : "en-US", {

src/components/tasks/TaskList.tsx

@@ -1,6 +1,7 @@
 "use client";
 import React, { useState, useEffect, useRef, useCallback } from "react";
 import { useI18n } from "@/lib/i18n";
+import { ContextMenu, MenuItem } from "@/components/ui/ContextMenu";
 
 export interface Task {
   id: string;
@@ -36,6 +37,7 @@ interface TaskItemProps {
   onToggle: (id: string, completed: boolean) => void;
   onUpdateTitle: (id: string, title: string) => void;
   onAddSubtask: (title: string, parentId: string) => void;
+  onContextMenu: (x: number, y: number, task: Task) => void;
   onDeleteTask?: (id: string) => void;
 }
 
@@ -46,6 +48,7 @@ function TaskItem({
   onToggle,
   onUpdateTitle,
   onAddSubtask,
+  onContextMenu,
 }: TaskItemProps) {
   const { t, lang } = useI18n();
   const [expanded, setExpanded] = useState(true);
@@ -116,6 +119,10 @@ function TaskItem({
       <div
         className={`task-item${task.completed ? " completed" : ""}${isSelected ? " selected" : ""}`}
         onClick={() => onSelect(task)}
+        onContextMenu={(e) => {
+          e.preventDefault();
+          onContextMenu(e.clientX, e.clientY, task);
+        }}
         id={`task-${task.id}`}
         style={{ group: "item" } as React.CSSProperties}
       >
@@ -406,6 +413,7 @@ export function TaskList({
   const [loading, setLoading] = useState(false);
   const [editingHeader, setEditingHeader] = useState(false);
   const [headerTitle, setHeaderTitle] = useState("");
+  const [contextMenu, setContextMenu] = useState<{ x: number; y: number; task: Task } | null>(null);
 
   const inputRef = useRef<HTMLInputElement>(null);
   const headerInputRef = useRef<HTMLInputElement>(null);
@@ -652,6 +660,7 @@ export function TaskList({
             onToggle={handleToggle}
             onUpdateTitle={(id, title) => onUpdateTaskTitle && onUpdateTaskTitle(id, title)}
             onAddSubtask={handleAddSubtaskInline}
+            onContextMenu={(x, y, tItem) => setContextMenu({ x, y, task: tItem })}
           />
         ))}
         {showCompleted && completedTasks.length > 0 && (
@@ -677,12 +686,55 @@ export function TaskList({
                 onToggle={handleToggle}
                 onUpdateTitle={(id, title) => onUpdateTaskTitle && onUpdateTaskTitle(id, title)}
                 onAddSubtask={handleAddSubtaskInline}
+                onContextMenu={(x, y, tItem) => setContextMenu({ x, y, task: tItem })}
               />
             ))}
           </div>
         )}
       </div>
 
+      {/* Context Menu on Task */}
+      {contextMenu && (
+        <ContextMenu
+          x={contextMenu.x}
+          y={contextMenu.y}
+          items={[
+            {
+              label: contextMenu.task.completed ? t("showDone") : t("completedSection"),
+              icon: contextMenu.task.completed ? "↩️" : "✅",
+              onClick: () => handleToggle(contextMenu.task.id, !contextMenu.task.completed),
+            },
+            {
+              label: t("taskTitlePlaceholder"),
+              icon: "✏️",
+              onClick: () => onTaskSelect(contextMenu.task),
+            },
+            {
+              label: t("subtasks"),
+              icon: "↳",
+              onClick: () => {
+                onTaskSelect(contextMenu.task);
+              },
+            },
+            { divider: true, label: "" },
+            {
+              label: t("deleteTaskConfirm").split("?")[0],
+              icon: "🗑️",
+              danger: true,
+              onClick: async () => {
+                if (isDemo) {
+                  setTasks((prev) => prev.filter((t) => t.id !== contextMenu.task.id));
+                } else {
+                  await fetch(`/api/tasks/${contextMenu.task.id}`, { method: "DELETE" });
+                  onRefresh();
+                }
+              },
+            },
+          ]}
+          onClose={() => setContextMenu(null)}
+        />
+      )}
+
       {/* Add task bar */}
       <div className="add-task-bar">
         <button className="task-check-btn" style={{ opacity: 0.4, flexShrink: 0 }} aria-hidden="true" />

src/components/ui/ContextMenu.tsx

@@ -0,0 +1,77 @@
+"use client";
+import React, { useEffect, useRef } from "react";
+
+export interface MenuItem {
+  label: string;
+  icon?: string | React.ReactNode;
+  danger?: boolean;
+  divider?: boolean;
+  onClick?: () => void;
+}
+
+interface ContextMenuProps {
+  x: number;
+  y: number;
+  items: MenuItem[];
+  onClose: () => void;
+}
+
+export function ContextMenu({ x, y, items, onClose }: ContextMenuProps) {
+  const menuRef = useRef<HTMLDivElement>(null);
+
+  useEffect(() => {
+    const handleClickOutside = (e: MouseEvent) => {
+      if (menuRef.current && !menuRef.current.contains(e.target as Node)) {
+        onClose();
+      }
+    };
+    const handleKeyDown = (e: KeyboardEvent) => {
+      if (e.key === "Escape") onClose();
+    };
+
+    document.addEventListener("mousedown", handleClickOutside);
+    document.addEventListener("keydown", handleKeyDown);
+    return () => {
+      document.removeEventListener("mousedown", handleClickOutside);
+      document.removeEventListener("keydown", handleKeyDown);
+    };
+  }, [onClose]);
+
+  // Adjust coordinates so menu stays inside viewport
+  const adjustedX = typeof window !== "undefined" ? Math.min(x, window.innerWidth - 180) : x;
+  const adjustedY = typeof window !== "undefined" ? Math.min(y, window.innerHeight - 250) : y;
+
+  return (
+    <div
+      ref={menuRef}
+      className="custom-context-menu"
+      style={{
+        position: "fixed",
+        top: adjustedY,
+        left: adjustedX,
+        zIndex: 9999,
+      }}
+      onClick={(e) => e.stopPropagation()}
+      onContextMenu={(e) => e.preventDefault()}
+    >
+      {items.map((item, i) => {
+        if (item.divider) {
+          return <div key={i} className="context-menu-divider" />;
+        }
+        return (
+          <div
+            key={i}
+            className={`context-menu-item${item.danger ? " danger" : ""}`}
+            onClick={() => {
+              if (item.onClick) item.onClick();
+              onClose();
+            }}
+          >
+            {item.icon && <span className="context-menu-icon">{item.icon}</span>}
+            <span style={{ flex: 1 }}>{item.label}</span>
+          </div>
+        );
+      })}
+    </div>
+  );
+}