diff --git a/src/zotero_kb/templates/index.html b/src/zotero_kb/templates/index.html
index 6a0f25e..4ac0629 100644
--- a/src/zotero_kb/templates/index.html
+++ b/src/zotero_kb/templates/index.html
@@ -156,13 +156,6 @@
       .window-shell:not([hidden]) {
         pointer-events: auto;
       }
-      .window-overlay {
-        position: fixed;
-        inset: 0;
-        z-index: 39;
-        background: rgba(24, 28, 22, 0.42);
-        border: 0;
-      }
       .window-frame {
         position: fixed;
         z-index: 40;
@@ -256,56 +249,8 @@
         min-height: 0;
         overflow: auto;
       }
-      .collection-item {
-        display: grid;
-        grid-template-columns: auto minmax(0, 1fr);
-        gap: 0.75rem;
-        align-items: center;
-        padding: 0.75rem 0.9rem;
-        border: 1px solid var(--line);
-        border-radius: 14px;
-        background: rgba(255, 255, 255, 0.72);
-      }
-      .collection-item input[type="checkbox"] {
-        width: auto;
-        margin: 0;
-      }
-      .item-row-body {
-        display: flex;
-        align-items: center;
-        gap: 0.55rem;
-        min-width: 0;
-      }
-      .title-button {
-        flex: 1;
-        min-width: 0;
-        padding: 0;
-        border: 0;
-        border-radius: 0;
-        background: transparent;
-        color: var(--ink);
-        text-align: left;
-        font-weight: 600;
-      }
-      .title-button:hover {
-        transform: none;
-        background: transparent;
-      }
-      .details-button {
-        width: 2.2rem;
-        min-width: 2.2rem;
-        padding: 0.45rem 0;
-      }
-      .collection-item .meta {
-        margin-left: auto;
-      }
-      .item-year {
-        flex: 0 0 auto;
-        min-width: 3rem;
-        text-align: right;
-      }
       .preview-popover {
-        position: fixed;
+        position: absolute;
         max-width: 28rem;
         padding: 0.85rem 1rem;
         border: 1px solid var(--line);
@@ -313,7 +258,6 @@
         background: rgba(255, 253, 248, 0.98);
         box-shadow: 0 18px 40px rgba(35, 31, 21, 0.16);
         color: var(--ink);
-        z-index: 60;
       }
       .tabs {
         display: flex;
@@ -343,18 +287,17 @@
           border-right: 0;
           border-bottom: 1px solid var(--line);
         }
-        .window-frame {
-          width: 100vw;
-          height: 100vh;
-          left: 0 !important;
-          top: 0 !important;
-          border-radius: 0;
+        .modal-card {
+          width: calc(100vw - 1rem);
+          margin: 0.5rem auto;
+          max-height: calc(100vh - 1rem);
         }
-        .window-body {
+        .modal-body {
           grid-template-columns: 1fr;
           grid-template-rows: minmax(12rem, 1fr) minmax(12rem, 1fr);
         }
-        .window-toolbar {
+        .modal-header,
+        .modal-action-bar {
           flex-wrap: wrap;
         }
       }
@@ -394,35 +337,44 @@
           <button id="open-import-modal-button" type="button">导入文献</button>
         </div>
 
-        <div id="import-modal" class="window-shell" hidden aria-hidden="true">
-          <div id="import-modal-overlay" class="window-overlay" type="button" aria-label="关闭导入弹窗"></div>
-          <section class="window-frame" role="dialog" aria-modal="true" aria-labelledby="import-modal-title">
-            <div class="window-toolbar">
-              <button id="close-import-modal-button" type="button" class="secondary">返回主页面</button>
-              <div>
-                <h3 id="import-modal-title">Import From Zotero</h3>
-                <p id="import-modal-project-label" class="meta">未选择项目</p>
-              </div>
-              <div class="window-toolbar-actions">
-                <div id="modal-selected-count" class="meta">已选 0 篇</div>
-                <button id="modal-clear-selection-button" type="button" class="danger">清空选择</button>
-                <button id="modal-import-selected-items-button" type="button">导入所选</button>
-              </div>
-            </div>
-            <div class="window-body">
-              <div class="window-pane collections">
-                <small>Collections</small>
-                <div id="collection-status" class="status"></div>
-                <div id="modal-collection-tree" class="window-scroll tree-list"></div>
-              </div>
-              <div class="window-pane items">
-                <small>Collection Items</small>
-                <div id="modal-collection-items" class="window-scroll collection-items-list"></div>
-              </div>
-            </div>
-            <div id="item-preview-popover" class="preview-popover" hidden></div>
-          </section>
+        <div id="import-window-shell" class="window-shell" hidden aria-hidden="true">
+  <section id="import-window" class="window-frame" role="dialog" aria-modal="true" aria-labelledby="import-window-title">
+    <div class="window-toolbar" id="import-window-toolbar">
+      <div style="display:flex;align-items:center;gap:0.6rem">
+        <span style="font-size:1.2rem;line-height:1">☰</span>
+        <div>
+          <h3 id="import-window-title">Import From Zotero</h3>
+          <p id="import-window-project-label" class="meta">未选择项目</p>
         </div>
+      </div>
+      <div class="window-toolbar-actions">
+        <div id="window-selected-count" class="meta">已选 0 篇</div>
+        <button id="window-clear-selection-button" type="button" class="danger">清空选择</button>
+        <button id="window-import-selected-items-button" type="button">导入所选</button>
+        <button id="window-minimize-button" type="button" class="secondary" title="最小化" style="width:auto;padding:0.55rem 0.75rem">_</button>
+        <button id="window-maximize-button" type="button" class="secondary" title="最大化" style="width:auto;padding:0.55rem 0.75rem">□</button>
+        <button id="window-close-button" type="button" class="secondary" title="关闭" style="width:auto;padding:0.55rem 0.75rem">×</button>
+      </div>
+    </div>
+    <div class="window-body">
+      <div class="window-pane collections">
+        <small>Collections</small>
+        <div id="window-collection-status" class="status"></div>
+        <div id="window-collection-tree" class="window-scroll tree-list"></div>
+      </div>
+      <div class="window-pane items">
+        <small>Collection Items</small>
+        <div id="window-collection-items" class="window-scroll collection-items-list"></div>
+      </div>
+    </div>
+    <div id="item-preview-popover" class="preview-popover" hidden></div>
+  </section>
+</div>
+
+<div id="import-window-minimized-bar" class="window-minimized-bar" hidden>
+  <span style="flex:1;text-align:left">导入文献</span>
+  <button id="window-restore-button" type="button" class="secondary" style="width:auto;padding:0.3rem 0.5rem;font-size:0.8rem">□</button>
+</div>
       </section>
 
       <section class="panel">
@@ -472,9 +424,22 @@
     </main>
 
     <script>
-      const ABSTRACT_PREVIEW_DELAY_MS = 3000;
+      const WINDOW_SESSION_STORAGE_KEY = "zotero-kb.import-window";
       const IMPORT_SESSION_STORAGE_KEY = "zotero-kb.import-modal";
 
+      function readWindowSessionState() {
+        try {
+          const raw = window.sessionStorage.getItem(WINDOW_SESSION_STORAGE_KEY);
+          if (!raw) return {};
+          const payload = JSON.parse(raw);
+          return typeof payload === "object" && payload ? payload : {};
+        } catch (_error) {
+          return {};
+        }
+      }
+
+      const windowSessionState = readWindowSessionState();
+
       function readImportSessionState() {
         try {
           const raw = window.sessionStorage.getItem(IMPORT_SESSION_STORAGE_KEY);
@@ -490,27 +455,12 @@
 
       const importSessionState = readImportSessionState();
 
-      const WINDOW_SESSION_STORAGE_KEY = "zotero-kb.import-window";
-
-      function readWindowSessionState() {
-        try {
-          const raw = window.sessionStorage.getItem(WINDOW_SESSION_STORAGE_KEY);
-          if (!raw) return {};
-          const payload = JSON.parse(raw);
-          return typeof payload === "object" && payload ? payload : {};
-        } catch (_error) {
-          return {};
-        }
-      }
-
-      const windowSessionState = readWindowSessionState();
-
       const state = {
         projects: [],
         currentProjectId: null,
         currentCards: [],
         collectionTree: [],
-        isImportModalOpen: false,
+        isImportWindowOpen: false,
         isImportWindowOpen: false,
         windowX: typeof windowSessionState.x === "number" ? windowSessionState.x : null,
         windowY: typeof windowSessionState.y === "number" ? windowSessionState.y : null,
@@ -541,9 +491,6 @@
         loadingCollectionKey: null,
         nextCollectionItemsRequestToken: 0,
         activeCollectionItemsRequestToken: 0,
-        hoveredItemKey: null,
-        hoverTimerId: null,
-        previewItemKey: null,
       };
 
       const elements = {
@@ -553,12 +500,12 @@
         importWindowShell: document.getElementById("import-window-shell"),
         importWindow: document.getElementById("import-window"),
         windowToolbar: document.getElementById("import-window-toolbar"),
+        openImportModalButton: document.getElementById("open-import-modal-button"),
         windowMinimizeButton: document.getElementById("window-minimize-button"),
         windowMaximizeButton: document.getElementById("window-maximize-button"),
         windowCloseButton: document.getElementById("window-close-button"),
         windowRestoreButton: document.getElementById("window-restore-button"),
         importWindowMinimizedBar: document.getElementById("import-window-minimized-bar"),
-        openImportModalButton: document.getElementById("open-import-modal-button"),
         windowProjectLabel: document.getElementById("import-window-project-label"),
         windowSelectedCount: document.getElementById("window-selected-count"),
         windowClearSelectionButton: document.getElementById("window-clear-selection-button"),
@@ -566,7 +513,6 @@
         windowCollectionStatus: document.getElementById("window-collection-status"),
         windowCollectionTree: document.getElementById("window-collection-tree"),
         windowCollectionItems: document.getElementById("window-collection-items"),
-        previewPopover: document.getElementById("item-preview-popover"),
         currentProjectLabel: document.getElementById("current-project-label"),
         cardList: document.getElementById("card-list"),
         cardDetail: document.getElementById("card-detail"),
@@ -616,6 +562,110 @@
         );
       }
 
+      function applyWindowPositionAndSize() {
+        const fw = elements.importWindow;
+        if (!fw) return;
+        fw.style.left = state.windowX !== null ? `${state.windowX}px` : "";
+        fw.style.top = state.windowY !== null ? `${state.windowY}px` : "";
+        fw.style.width = state.windowWidth !== null ? `${state.windowWidth}px` : "";
+        fw.style.height = state.windowHeight !== null ? `${state.windowHeight}px` : "";
+      }
+
+      function initWindowFromSession() {
+        const fw = elements.importWindow;
+        const bar = elements.importWindowMinimizedBar;
+        if (state.isWindowMinimized) {
+          fw.classList.add("minimized");
+          fw.classList.remove("maximized");
+          bar.hidden = false;
+        } else if (state.isWindowMaximized) {
+          fw.classList.add("maximized");
+          fw.classList.remove("minimized");
+          fw.style.width = "100vw";
+          fw.style.height = "100vh";
+          fw.style.left = "0";
+          fw.style.top = "0";
+          bar.hidden = true;
+        } else {
+          if (state.windowX !== null) {
+            applyWindowPositionAndSize();
+          }
+          fw.classList.remove("minimized", "maximized");
+          bar.hidden = true;
+        }
+      }
+
+      function startWindowDrag(event) {
+        const fw = elements.importWindow;
+        if (!fw || fw.classList.contains("maximized") || fw.classList.contains("minimized")) return;
+        event.preventDefault();
+        state.isWindowDragging = true;
+        state.windowDragStartX = event.clientX;
+        state.windowDragStartY = event.clientY;
+        state.windowDragStartLeft = parseFloat(fw.style.left) || 0;
+        state.windowDragStartTop = parseFloat(fw.style.top) || 0;
+        fw.style.transition = "none";
+      }
+
+      function moveWindowDrag(event) {
+        if (!state.isWindowDragging) return;
+        event.preventDefault();
+        const fw = elements.importWindow;
+        const dx = event.clientX - state.windowDragStartX;
+        const dy = event.clientY - state.windowDragStartY;
+        let newLeft = state.windowDragStartLeft + dx;
+        let newTop = state.windowDragStartTop + dy;
+        const maxLeft = window.innerWidth - (parseFloat(fw.style.width) || fw.offsetWidth);
+        const maxTop = window.innerHeight - (parseFloat(fw.style.height) || fw.offsetHeight);
+        newLeft = Math.max(0, Math.min(newLeft, maxLeft));
+        newTop = Math.max(0, Math.min(newTop, maxTop));
+        fw.style.left = `${newLeft}px`;
+        fw.style.top = `${newTop}px`;
+        state.windowX = newLeft;
+        state.windowY = newTop;
+      }
+
+      function endWindowDrag() {
+        if (!state.isWindowDragging) return;
+        state.isWindowDragging = false;
+        persistWindowSessionState();
+      }
+
+      function minimizeWindow() {
+        state.isWindowMinimized = true;
+        state.isWindowMaximized = false;
+        elements.importWindow.classList.add("minimized");
+        elements.importWindow.classList.remove("maximized");
+        elements.importWindowMinimizedBar.hidden = false;
+        persistWindowSessionState();
+      }
+
+      function maximizeWindow() {
+        state.isWindowMaximized = !state.isWindowMaximized;
+        if (state.isWindowMaximized) {
+          state.isWindowMinimized = false;
+          elements.importWindow.classList.add("maximized");
+          elements.importWindow.classList.remove("minimized");
+          elements.importWindowMinimizedBar.hidden = true;
+          elements.importWindow.style.width = "100vw";
+          elements.importWindow.style.height = "100vh";
+          elements.importWindow.style.left = "0";
+          elements.importWindow.style.top = "0";
+        } else {
+          elements.importWindow.classList.remove("maximized");
+          applyWindowPositionAndSize();
+        }
+        persistWindowSessionState();
+      }
+
+      function restoreWindow() {
+        state.isWindowMinimized = false;
+        elements.importWindow.classList.remove("minimized");
+        elements.importWindowMinimizedBar.hidden = true;
+        applyWindowPositionAndSize();
+        persistWindowSessionState();
+      }
+
       function setStatus(target, message, isError = false) {
         target.textContent = message || "";
         target.classList.toggle("error", Boolean(isError));
@@ -661,7 +711,7 @@
       function renderCards(cards) {
         state.currentCards = cards || [];
         if (!state.currentCards.length) {
-          elements.cardList.innerHTML = '<div class="empty">当前项目还没有卡片。先从 Zotero 导入文献。</div>';
+          elements.cardList.innerHTML = '<div class="empty">当前项目还没有卡片。先导入 Zotero 选中文献。</div>';
           elements.cardDetail.innerHTML = '<div class="empty">导入后点击卡片查看详情。</div>';
           return;
         }
@@ -731,75 +781,7 @@
       }
 
       function renderSelectedCount() {
-        elements.selectedCount.textContent = `已选 ${state.selectedItemKeys.size} 篇`;
-      }
-
-      function clearAbstractPreviewTimer() {
-        if (state.hoverTimerId !== null) {
-          window.clearTimeout(state.hoverTimerId);
-          state.hoverTimerId = null;
-        }
-      }
-
-      function cancelAbstractPreview() {
-        clearAbstractPreviewTimer();
-        state.hoveredItemKey = null;
-        state.previewItemKey = null;
-        elements.previewPopover.hidden = true;
-        elements.previewPopover.setAttribute("aria-hidden", "true");
-        elements.previewPopover.textContent = "";
-        elements.previewPopover.style.top = "";
-        elements.previewPopover.style.left = "";
-      }
-
-      function positionAbstractPreview(target) {
-        const preview = elements.previewPopover;
-        const targetRect = target.getBoundingClientRect();
-        const maxWidth = Math.min(448, Math.max(260, window.innerWidth - 32));
-        preview.style.maxWidth = `${maxWidth}px`;
-        const previewRect = preview.getBoundingClientRect();
-        let left = targetRect.right + 12;
-        if (left + previewRect.width > window.innerWidth - 12) {
-          left = Math.max(12, targetRect.left - previewRect.width - 12);
-        }
-        let top = targetRect.top;
-        if (top + previewRect.height > window.innerHeight - 12) {
-          top = Math.max(12, window.innerHeight - previewRect.height - 12);
-        }
-        preview.style.left = `${Math.round(left)}px`;
-        preview.style.top = `${Math.round(top)}px`;
-      }
-
-      function showAbstractPreview(item, target) {
-        clearAbstractPreviewTimer();
-        const abstract = typeof item.abstract === "string" ? item.abstract.trim() : "";
-        if (!abstract) {
-          cancelAbstractPreview();
-          return;
-        }
-        state.previewItemKey = item.item_key;
-        elements.previewPopover.textContent = abstract;
-        elements.previewPopover.hidden = false;
-        elements.previewPopover.setAttribute("aria-hidden", "false");
-        positionAbstractPreview(target);
-      }
-
-      function scheduleAbstractPreview(item, target) {
-        if (!window.matchMedia("(hover: hover) and (pointer: fine)").matches) {
-          return;
-        }
-        const abstract = typeof item.abstract === "string" ? item.abstract.trim() : "";
-        if (!abstract) {
-          return;
-        }
-        cancelAbstractPreview();
-        state.hoveredItemKey = item.item_key;
-        state.hoverTimerId = window.setTimeout(() => {
-          state.hoverTimerId = null;
-          if (state.hoveredItemKey === item.item_key) {
-            showAbstractPreview(item, target);
-          }
-        }, ABSTRACT_PREVIEW_DELAY_MS);
+        elements.windowSelectedCount.textContent = `已选 ${state.selectedItemKeys.size} 篇`;
       }
 
       function resetCollectionItemsLoadingState(clearItems = false) {
@@ -816,20 +798,20 @@
         if (currentProject) {
           const label = `当前项目：${currentProject.name}`;
           elements.currentProjectLabel.textContent = label;
-          elements.importModalProjectLabel.textContent = label;
+          elements.windowProjectLabel.textContent = label;
           return;
         }
         elements.currentProjectLabel.textContent = "当前未选择项目。";
-        elements.importModalProjectLabel.textContent = "未选择项目";
+        elements.windowProjectLabel.textContent = "未选择项目";
       }
 
       function updateImportActionState() {
         const hasProject = Boolean(state.currentProjectId);
         const hasSelection = state.selectedItemKeys.size > 0;
         syncCurrentProjectLabels();
-        elements.importSelectedItemsButton.disabled = !hasProject || !hasSelection;
-        elements.importSelectedItemsButton.title = !hasProject ? "请先选择项目" : (hasSelection ? "" : "请先选择文献");
-        elements.clearSelectionButton.disabled = !state.selectedItemKeys.size;
+        elements.windowImportSelectedItemsButton.disabled = !hasProject || !hasSelection;
+        elements.windowImportSelectedItemsButton.title = !hasProject ? "请先选择项目" : (hasSelection ? "" : "请先选择文献");
+        elements.windowClearSelectionButton.disabled = !state.selectedItemKeys.size;
         renderSelectedCount();
       }
 
@@ -873,11 +855,11 @@
 
       function renderCollectionTree() {
         if (!state.collectionTree.length) {
-          elements.collectionTree.innerHTML = '<div class="empty">暂无 collection。</div>';
+          elements.windowCollectionTree.innerHTML = '<div class="empty">暂无 collection。</div>';
           return;
         }
 
-        elements.collectionTree.innerHTML = "";
+        elements.windowCollectionTree.innerHTML = "";
         const fragment = document.createDocumentFragment();
 
         function appendNode(node, depth) {
@@ -918,11 +900,11 @@
           button.style.textAlign = "left";
           button.innerHTML = `
             <strong>${node.name}</strong>
-            <div class="meta">${node.direct_item_count} 篇</div>
+            <div class="meta">${node.direct_item_count} 篇直接文献 · ${node.descendant_item_count} 篇含子目录</div>
           `;
           button.addEventListener("click", () => {
             loadCollectionItems(node.collection_key).catch((error) => {
-              setStatus(elements.collectionStatus, error.message, true);
+              setStatus(elements.windowCollectionStatus, error.message, true);
             });
           });
           row.appendChild(button);
@@ -939,74 +921,51 @@
         for (const node of state.collectionTree) {
           appendNode(node, 0);
         }
-        elements.collectionTree.appendChild(fragment);
+        elements.windowCollectionTree.appendChild(fragment);
       }
 
       function renderCollectionItems() {
-        cancelAbstractPreview();
         if (!state.selectedCollectionKey) {
-          elements.collectionItems.innerHTML = '<div class="empty">先选择一个 collection。</div>';
+          elements.windowCollectionItems.innerHTML = '<div class="empty">先选择一个 collection。</div>';
           updateImportActionState();
           return;
         }
         if (!state.collectionItemsLoaded) {
-          elements.collectionItems.innerHTML = state.loadingCollectionKey === state.selectedCollectionKey
+          elements.windowCollectionItems.innerHTML = state.loadingCollectionKey === state.selectedCollectionKey
             ? '<div class="empty">正在加载当前 collection 文献。</div>'
             : '<div class="empty">当前 collection 文献尚未加载。</div>';
           updateImportActionState();
           return;
         }
         if (!state.visibleCollectionItems.length) {
-          elements.collectionItems.innerHTML = '<div class="empty">当前目录下没有可导入文献。</div>';
+          elements.windowCollectionItems.innerHTML = '<div class="empty">当前目录及子目录下没有可导入文献。</div>';
           updateImportActionState();
           return;
         }
 
-        elements.collectionItems.innerHTML = "";
+        elements.windowCollectionItems.innerHTML = "";
         for (const item of state.visibleCollectionItems) {
-          const row = document.createElement("div");
-          row.className = "collection-item";
-          const hasAbstract = typeof item.abstract === "string" && item.abstract.trim().length > 0;
+          const row = document.createElement("label");
+          row.className = "project-item";
+          row.style.display = "grid";
+          row.style.gridTemplateColumns = "auto 1fr";
+          row.style.gap = "0.75rem";
+          row.style.alignItems = "start";
           row.innerHTML = `
             <input type="checkbox" ${state.selectedItemKeys.has(item.item_key) ? "checked" : ""} />
-            <div class="item-row-body">
-              <button type="button" class="title-button">${item.title}</button>
-              <div class="meta item-year">${item.year || "-"}</div>
-              <button
-                type="button"
-                class="secondary details-button"
-                aria-label="${hasAbstract ? "查看摘要" : "暂无摘要"}"
-                ${hasAbstract ? "" : "disabled"}
-              >i</button>
+            <div>
+              <strong>${item.title}</strong>
+              <div class="meta">${item.item_key} · ${item.year || "-"} · ${item.item_type || "-"}</div>
             </div>
           `;
-          const checkbox = row.querySelector("input");
-          const titleButton = row.querySelector(".title-button");
-          const detailsButton = row.querySelector(".details-button");
-          checkbox.addEventListener("change", () => {
-            cancelAbstractPreview();
-            toggleItemSelection(item.item_key);
-          });
-          titleButton.addEventListener("mouseenter", () => scheduleAbstractPreview(item, titleButton));
-          titleButton.addEventListener("mouseleave", cancelAbstractPreview);
-          detailsButton.addEventListener("click", (event) => {
-            event.preventDefault();
-            if (!hasAbstract) {
-              return;
-            }
-            if (state.previewItemKey === item.item_key && !elements.previewPopover.hidden) {
-              cancelAbstractPreview();
-              return;
-            }
-            showAbstractPreview(item, detailsButton);
-          });
-          elements.collectionItems.appendChild(row);
+          row.querySelector("input").addEventListener("change", () => toggleItemSelection(item.item_key));
+          elements.windowCollectionItems.appendChild(row);
         }
         updateImportActionState();
       }
 
       async function loadCollectionTree() {
-        setStatus(elements.collectionStatus, "正在加载 collection...");
+        setStatus(elements.windowCollectionStatus, "正在加载 collection...");
         const payload = await api("/api/zotero/collections/tree");
         state.collectionTree = Array.isArray(payload.collections) ? payload.collections : [];
         normalizeSelectedCollectionKey();
@@ -1020,11 +979,10 @@
         state.visibleCollectionItems = [];
         resetCollectionItemsLoadingState();
         renderCollectionItems();
-        setStatus(elements.collectionStatus, "");
+        setStatus(elements.windowCollectionStatus, "");
       }
 
       async function loadCollectionItems(collectionKey) {
-        cancelAbstractPreview();
         if (!state.collectionItemsLoaded && state.loadingCollectionKey === collectionKey) {
           return;
         }
@@ -1033,7 +991,7 @@
           resetCollectionItemsLoadingState(true);
           renderCollectionTree();
           renderCollectionItems();
-          setStatus(elements.collectionStatus, state.selectedCollectionKey ? "已切换到可用 collection。" : "");
+          setStatus(elements.windowCollectionStatus, state.selectedCollectionKey ? "已切换到可用 collection。" : "");
           if (state.selectedCollectionKey) {
             await loadCollectionItems(state.selectedCollectionKey);
           }
@@ -1048,9 +1006,9 @@
         state.nextCollectionItemsRequestToken = requestToken;
         state.activeCollectionItemsRequestToken = requestToken;
         renderCollectionItems();
-        setStatus(elements.collectionStatus, "正在加载文献...");
+        setStatus(elements.windowCollectionStatus, "正在加载文献...");
         try {
-          const payload = await api(`/api/zotero/collections/${collectionKey}/items?include_descendants=false`);
+          const payload = await api(`/api/zotero/collections/${collectionKey}/items`);
           if (state.activeCollectionItemsRequestToken !== requestToken || state.selectedCollectionKey !== collectionKey) {
             return;
           }
@@ -1060,8 +1018,8 @@
           renderCollectionItems();
           const visibleCount = state.visibleCollectionItems.length;
           setStatus(
-            elements.collectionStatus,
-            visibleCount ? `当前目录共 ${visibleCount} 篇文献。` : "当前目录下没有可导入文献。"
+            elements.windowCollectionStatus,
+            visibleCount ? `当前目录及子目录共 ${visibleCount} 篇文献。` : "当前目录及子目录下没有可导入文献。"
           );
         } catch (error) {
           if (state.activeCollectionItemsRequestToken === requestToken) {
@@ -1073,7 +1031,6 @@
       }
 
       function toggleItemSelection(itemKey) {
-        cancelAbstractPreview();
         if (state.selectedItemKeys.has(itemKey)) {
           state.selectedItemKeys.delete(itemKey);
         } else {
@@ -1084,8 +1041,16 @@
         updateImportActionState();
       }
 
+      function selectVisibleItems() {
+        for (const item of state.visibleCollectionItems) {
+          state.selectedItemKeys.add(item.item_key);
+        }
+        persistImportSessionState();
+        renderCollectionItems();
+        updateImportActionState();
+      }
+
       function clearSelectedItems() {
-        cancelAbstractPreview();
         state.selectedItemKeys.clear();
         persistImportSessionState();
         renderCollectionItems();
@@ -1093,12 +1058,11 @@
       }
 
       async function importSelectedItems() {
-        cancelAbstractPreview();
         if (!state.currentProjectId || !state.selectedItemKeys.size) {
           updateImportActionState();
           return;
         }
-        setStatus(elements.collectionStatus, "正在导入...");
+        setStatus(elements.windowCollectionStatus, "正在导入...");
         const payload = await api(`/api/projects/${state.currentProjectId}/imports/item-keys`, {
           method: "POST",
           body: JSON.stringify({ item_keys: Array.from(state.selectedItemKeys) }),
@@ -1107,23 +1071,24 @@
         persistImportSessionState();
         renderCollectionItems();
         renderCards(payload.project_view?.cards || []);
-        setStatus(elements.collectionStatus, "导入完成。");
+        setStatus(elements.windowCollectionStatus, "导入完成。");
         updateImportActionState();
-        closeImportModal();
+        closeImportWindow();
       }
 
-      async function openImportModal() {
-        state.isImportModalOpen = true;
-        elements.importModal.hidden = false;
-        elements.importModal.setAttribute("aria-hidden", "false");
+      async function openImportWindow() {
+        state.isImportWindowOpen = true;
+        elements.importWindowShell.hidden = false;
+        elements.importWindowShell.setAttribute("aria-hidden", "false");
         document.body.classList.toggle("modal-open", true);
         cancelAbstractPreview();
         updateImportActionState();
+        initWindowFromSession();
         if (!state.collectionTree.length) {
           try {
             await loadCollectionTree();
           } catch (error) {
-            setStatus(elements.collectionStatus, error.message, true);
+            setStatus(elements.windowCollectionStatus, error.message, true);
           }
         } else if (
           state.selectedCollectionKey &&
@@ -1132,7 +1097,7 @@
           try {
             await loadCollectionItems(state.selectedCollectionKey);
           } catch (error) {
-            setStatus(elements.collectionStatus, error.message, true);
+            setStatus(elements.windowCollectionStatus, error.message, true);
           }
         } else {
           renderCollectionTree();
@@ -1140,10 +1105,10 @@
         }
       }
 
-      function closeImportModal() {
-        state.isImportModalOpen = false;
-        elements.importModal.hidden = true;
-        elements.importModal.setAttribute("aria-hidden", "true");
+      function closeImportWindow() {
+        state.isImportWindowOpen = false;
+        elements.importWindowShell.hidden = true;
+        elements.importWindowShell.setAttribute("aria-hidden", "true");
         document.body.classList.toggle("modal-open", false);
         cancelAbstractPreview();
       }
@@ -1212,20 +1177,28 @@
       elements.refreshProjectsButton.addEventListener("click", loadProjects);
 
       elements.openImportModalButton.addEventListener("click", () => {
-        openImportModal();
+        openImportWindow();
       });
-      elements.closeImportModalButton.addEventListener("click", closeImportModal);
-      elements.importModalOverlay.addEventListener("click", closeImportModal);
-      elements.collectionItems.addEventListener("scroll", cancelAbstractPreview);
-      elements.clearSelectionButton.addEventListener("click", clearSelectedItems);
-      elements.importSelectedItemsButton.addEventListener("click", () => {
+      elements.windowCloseButton.addEventListener("click", closeImportWindow);
+      elements.windowMinimizeButton.addEventListener("click", minimizeWindow);
+      elements.windowMaximizeButton.addEventListener("click", maximizeWindow);
+      elements.windowRestoreButton.addEventListener("click", restoreWindow);
+      elements.importWindowMinimizedBar.addEventListener("click", (e) => {
+        if (e.target === elements.windowRestoreButton) return;
+        restoreWindow();
+      });
+      elements.windowToolbar.addEventListener("pointerdown", startWindowDrag);
+      document.addEventListener("pointermove", moveWindowDrag);
+      document.addEventListener("pointerup", endWindowDrag);
+      elements.windowClearSelectionButton.addEventListener("click", clearSelectedItems);
+      elements.windowImportSelectedItemsButton.addEventListener("click", () => {
         importSelectedItems().catch((error) => {
-          setStatus(elements.collectionStatus, error.message, true);
+          setStatus(elements.windowCollectionStatus, error.message, true);
         });
       });
       document.addEventListener("keydown", (event) => {
-        if (event.key === "Escape" && state.isImportModalOpen) {
-          closeImportModal();
+        if (event.key === "Escape" && state.isImportWindowOpen) {
+          closeImportWindow();
         }
       });
 
@@ -1280,7 +1253,7 @@
       elements.recommendTab.addEventListener("click", () => activateTab("recommend"));
       elements.planTab.addEventListener("click", () => activateTab("plan"));
 
-      closeImportModal();
+      closeImportWindow();
       updateImportActionState();
       loadProjects().catch((error) => {
         setStatus(elements.projectStatus, error.message, true);
diff --git a/tests/test_ui.py b/tests/test_ui.py
index 2eb2397..ff85c23 100644
--- a/tests/test_ui.py
+++ b/tests/test_ui.py
@@ -26,21 +26,42 @@ def test_index_contains_base_page_forms(tmp_path) -> None:
     assert 'id="plan-form"' in html
 
 
-def test_index_contains_import_modal_controls(tmp_path) -> None:
+def test_index_contains_import_window_controls(tmp_path) -> None:
     html = _get_index_html(tmp_path)
 
     assert 'id="open-import-modal-button"' in html
-    assert 'id="import-modal"' in html
-    assert 'id="close-import-modal-button"' in html
-    assert 'id="modal-collection-tree"' in html
-    assert 'id="modal-collection-items"' in html
-    assert 'id="modal-selected-count"' in html
-    assert 'id="modal-select-descendants-button"' in html
-    assert 'id="modal-clear-selection-button"' in html
-    assert 'id="modal-import-selected-items-button"' in html
+    assert 'id="import-window-shell"' in html
+    assert 'id="window-minimize-button"' in html
+    assert 'id="window-maximize-button"' in html
+    assert 'id="window-close-button"' in html
+    assert 'id="window-restore-button"' in html
+    assert 'id="import-window-minimized-bar"' in html
+    assert 'id="import-window-project-label"' in html
+    assert 'id="window-collection-tree"' in html
+    assert 'id="window-collection-items"' in html
+    assert 'id="window-selected-count"' in html
+    assert 'id="window-clear-selection-button"' in html
+    assert 'id="window-import-selected-items-button"' in html
     assert 'id="item-preview-popover"' in html
-    assert 'isImportModalOpen: false' in html
-    assert "function openImportModal()" in html
-    assert "function closeImportModal()" in html
+    assert 'isImportWindowOpen: false' in html
+    assert "function openImportWindow()" in html
+    assert "function closeImportWindow()" in html
     assert "function updateImportActionState()" in html
     assert 'document.body.classList.toggle("modal-open"' in html
+
+
+def test_index_window_frame_css(tmp_path) -> None:
+    html = _get_index_html(tmp_path)
+
+    assert ".window-frame" in html
+    assert ".window-shell" in html
+    assert ".window-toolbar" in html
+    assert ".window-body" in html
+    assert ".window-minimized-bar" in html
+    assert '"zotero-kb.import-window"' in html
+    assert "startWindowDrag" in html
+    assert "minimizeWindow" in html
+    assert "maximizeWindow" in html
+    assert "restoreWindow" in html
+    assert "initWindowFromSession" in html
+    assert "persistWindowSessionState" in html