diff --git a/src/zotero_kb/templates/index.html b/src/zotero_kb/templates/index.html
index 398ce3b..2be9326 100644
--- a/src/zotero_kb/templates/index.html
+++ b/src/zotero_kb/templates/index.html
@@ -144,74 +144,168 @@
         border-radius: 16px;
         color: var(--muted);
       }
-      .modal-shell[hidden] {
+      .window-shell[hidden] {
         display: none;
       }
-      .modal-shell {
+      .window-shell {
         position: fixed;
         inset: 0;
         z-index: 40;
+        pointer-events: none;
       }
-      .modal-overlay {
-        position: absolute;
+      .window-shell:not([hidden]) {
+        pointer-events: auto;
+      }
+      .window-overlay {
+        position: fixed;
         inset: 0;
-        border-radius: 0;
+        z-index: 39;
         background: rgba(24, 28, 22, 0.42);
+        border: 0;
       }
-      .modal-card {
-        position: relative;
-        z-index: 1;
-        width: min(1100px, calc(100vw - 2rem));
-        max-height: calc(100vh - 2rem);
-        margin: 1rem auto;
+      .window-frame {
+        position: fixed;
+        z-index: 40;
+        width: var(--fw-width, 90vw);
+        height: var(--fw-height, 75vh);
+        left: var(--fw-left, calc((100vw - var(--fw-width, 90vw)) / 2));
+        top: var(--fw-top, calc((100vh - var(--fw-height, 75vh)) / 2));
+        min-width: 40rem;
+        min-height: 30rem;
+        border-radius: 16px;
+        box-shadow: 0 24px 64px rgba(35, 31, 21, 0.22);
         display: grid;
-        grid-template-rows: auto auto 1fr auto;
+        grid-template-rows: auto 1fr auto;
+        overflow: hidden;
         background: var(--surface);
         border: 1px solid var(--line);
-        border-radius: 24px;
-        box-shadow: 0 24px 60px rgba(35, 31, 21, 0.2);
-        overflow: hidden;
       }
-      .modal-header,
-      .modal-action-bar {
+      .window-frame.maximized {
+        width: 100vw;
+        height: 100vh;
+        left: 0 !important;
+        top: 0 !important;
+        border-radius: 0;
+        --fw-width: 100vw;
+        --fw-height: 100vh;
+      }
+      .window-frame:not(.maximized):not(.minimized) {
+        resize: both;
+        overflow: auto;
+      }
+      .window-minimized-bar {
+        position: fixed;
+        bottom: 1rem;
+        right: 1rem;
+        z-index: 50;
+        height: 2.5rem;
+        width: 14rem;
+        border-radius: 8px;
+        background: var(--surface);
+        border: 1px solid var(--line);
+        box-shadow: 0 8px 24px rgba(35, 31, 21, 0.14);
+        display: none;
+        align-items: center;
+        padding: 0 0.75rem;
+        gap: 0.5rem;
+        cursor: pointer;
+        font-size: 0.9rem;
+        font-weight: 600;
+        color: var(--ink);
+      }
+      .window-minimized-bar:not([hidden]) {
+        display: flex;
+      }
+      .window-minimized-bar:hover {
+        background: var(--panel);
+      }
+      .window-toolbar {
         display: flex;
         align-items: center;
         justify-content: space-between;
-        gap: 0.75rem;
+        gap: 1rem;
         padding: 1rem 1.25rem;
         border-bottom: 1px solid var(--line);
+        background: rgba(255, 253, 248, 0.98);
+        cursor: grab;
       }
-      .modal-action-bar {
-        border-top: 1px solid var(--line);
-        border-bottom: 0;
-        position: sticky;
-        bottom: 0;
-        z-index: 2;
-        background: var(--surface);
+      .window-toolbar:active {
+        cursor: grabbing;
       }
-      .modal-header-actions {
+      .window-toolbar-actions {
         display: flex;
         align-items: center;
         gap: 0.75rem;
         flex-wrap: wrap;
       }
-      .modal-body {
+      .window-body {
         display: grid;
-        grid-template-columns: minmax(280px, 0.9fr) minmax(0, 1.2fr);
-        min-height: 24rem;
-      }
-      .modal-pane {
-        display: grid;
-        gap: 0.6rem;
-        padding: 1rem 1.25rem;
+        grid-template-columns: 22rem minmax(0, 1fr);
         min-height: 0;
       }
-      .modal-scroll {
+      .window-pane {
+        display: grid;
+        gap: 0.6rem;
+        min-height: 0;
+        padding: 1rem 1.25rem;
+      }
+      .window-pane.collections {
+        border-right: 1px solid var(--line);
+      }
+      .window-scroll {
         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: absolute;
+        position: fixed;
         max-width: 28rem;
         padding: 0.85rem 1rem;
         border: 1px solid var(--line);
@@ -219,6 +313,7 @@
         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;
@@ -248,17 +343,18 @@
           border-right: 0;
           border-bottom: 1px solid var(--line);
         }
-        .modal-card {
-          width: calc(100vw - 1rem);
-          margin: 0.5rem auto;
-          max-height: calc(100vh - 1rem);
+        .window-frame {
+          width: 100vw;
+          height: 100vh;
+          left: 0 !important;
+          top: 0 !important;
+          border-radius: 0;
         }
-        .modal-body {
+        .window-body {
           grid-template-columns: 1fr;
           grid-template-rows: minmax(12rem, 1fr) minmax(12rem, 1fr);
         }
-        .modal-header,
-        .modal-action-bar {
+        .window-toolbar {
           flex-wrap: wrap;
         }
       }
@@ -298,35 +394,32 @@
           <button id="open-import-modal-button" type="button">导入文献</button>
         </div>
 
-        <div id="import-modal" class="modal-shell" hidden aria-hidden="true">
-          <button id="import-modal-overlay" class="modal-overlay" type="button" aria-label="关闭导入弹窗"></button>
-          <section class="modal-card" role="dialog" aria-modal="true" aria-labelledby="import-modal-title">
-            <header class="modal-header">
+        <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="modal-header-actions">
+              <div class="window-toolbar-actions">
                 <div id="modal-selected-count" class="meta">已选 0 篇</div>
-                <button id="close-import-modal-button" type="button" class="secondary">关闭</button>
-              </div>
-            </header>
-            <div id="collection-status" class="status"></div>
-            <div class="modal-body">
-              <div class="modal-pane">
-                <small>Collections</small>
-                <div id="modal-collection-tree" class="modal-scroll tree-list"></div>
-              </div>
-              <div class="modal-pane">
-                <small>Collection Items</small>
-                <div id="modal-collection-items" class="modal-scroll collection-items-list"></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>
-            <footer class="modal-action-bar">
-              <button id="modal-select-descendants-button" type="button" class="secondary">全选当前目录及子目录</button>
-              <button id="modal-clear-selection-button" type="button" class="danger">清空选择</button>
-              <button id="modal-import-selected-items-button" type="button">导入所选到当前项目</button>
-            </footer>
             <div id="item-preview-popover" class="preview-popover" hidden></div>
           </section>
         </div>
@@ -379,6 +472,7 @@
     </main>
 
     <script>
+      const ABSTRACT_PREVIEW_DELAY_MS = 3000;
       const IMPORT_SESSION_STORAGE_KEY = "zotero-kb.import-modal";
 
       function readImportSessionState() {
@@ -420,6 +514,9 @@
         loadingCollectionKey: null,
         nextCollectionItemsRequestToken: 0,
         activeCollectionItemsRequestToken: 0,
+        hoveredItemKey: null,
+        hoverTimerId: null,
+        previewItemKey: null,
       };
 
       const elements = {
@@ -435,9 +532,9 @@
         collectionTree: document.getElementById("modal-collection-tree"),
         collectionItems: document.getElementById("modal-collection-items"),
         selectedCount: document.getElementById("modal-selected-count"),
-        selectDescendantsButton: document.getElementById("modal-select-descendants-button"),
         clearSelectionButton: document.getElementById("modal-clear-selection-button"),
         importSelectedItemsButton: document.getElementById("modal-import-selected-items-button"),
+        previewPopover: document.getElementById("item-preview-popover"),
         currentProjectLabel: document.getElementById("current-project-label"),
         cardList: document.getElementById("card-list"),
         cardDetail: document.getElementById("card-detail"),
@@ -511,7 +608,7 @@
       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。先导入 Zotero 选中文献。</div>';
+          elements.cardList.innerHTML = '<div class="empty">当前项目还没有卡片。先从 Zotero 导入文献。</div>';
           elements.cardDetail.innerHTML = '<div class="empty">导入后点击卡片查看详情。</div>';
           return;
         }
@@ -584,6 +681,74 @@
         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 = `${Math.round(top)}px`;
+      }
+
+      function showAbstractPreview(item, target) {
+        clearAbstractPreviewTimer();
+        const abstract = typeof item.abstract === "string" ? item.abstract.trim() : "";
+        if (!abstract) {
+          cancelAbstractPreview();
+          return;
+        }
+        state.previewItemKey = item.item_key;
+        elements.previewPopover.textContent = abstract;
+        elements.previewPopover.hidden = false;
+        elements.previewPopover.setAttribute("aria-hidden", "false");
+        positionAbstractPreview(target);
+      }
+
+      function scheduleAbstractPreview(item, target) {
+        if (!window.matchMedia("(hover: hover) and (pointer: fine)").matches) {
+          return;
+        }
+        const abstract = typeof item.abstract === "string" ? item.abstract.trim() : "";
+        if (!abstract) {
+          return;
+        }
+        cancelAbstractPreview();
+        state.hoveredItemKey = item.item_key;
+        state.hoverTimerId = window.setTimeout(() => {
+          state.hoverTimerId = null;
+          if (state.hoveredItemKey === item.item_key) {
+            showAbstractPreview(item, target);
+          }
+        }, ABSTRACT_PREVIEW_DELAY_MS);
+      }
+
       function resetCollectionItemsLoadingState(clearItems = false) {
         if (clearItems) {
           state.visibleCollectionItems = [];
@@ -611,7 +776,6 @@
         syncCurrentProjectLabels();
         elements.importSelectedItemsButton.disabled = !hasProject || !hasSelection;
         elements.importSelectedItemsButton.title = !hasProject ? "请先选择项目" : (hasSelection ? "" : "请先选择文献");
-        elements.selectDescendantsButton.disabled = !state.collectionItemsLoaded || !state.visibleCollectionItems.length;
         elements.clearSelectionButton.disabled = !state.selectedItemKeys.size;
         renderSelectedCount();
       }
@@ -701,7 +865,7 @@
           button.style.textAlign = "left";
           button.innerHTML = `
             <strong>${node.name}</strong>
-            <div class="meta">${node.direct_item_count} 篇直接文献 · ${node.descendant_item_count} 篇含子目录</div>
+            <div class="meta">${node.direct_item_count} 篇</div>
           `;
           button.addEventListener("click", () => {
             loadCollectionItems(node.collection_key).catch((error) => {
@@ -726,6 +890,7 @@
       }
 
       function renderCollectionItems() {
+        cancelAbstractPreview();
         if (!state.selectedCollectionKey) {
           elements.collectionItems.innerHTML = '<div class="empty">先选择一个 collection。</div>';
           updateImportActionState();
@@ -739,27 +904,49 @@
           return;
         }
         if (!state.visibleCollectionItems.length) {
-          elements.collectionItems.innerHTML = '<div class="empty">当前目录及子目录下没有可导入文献。</div>';
+          elements.collectionItems.innerHTML = '<div class="empty">当前目录下没有可导入文献。</div>';
           updateImportActionState();
           return;
         }
 
         elements.collectionItems.innerHTML = "";
         for (const item of state.visibleCollectionItems) {
-          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";
+          const row = document.createElement("div");
+          row.className = "collection-item";
+          const hasAbstract = typeof item.abstract === "string" && item.abstract.trim().length > 0;
           row.innerHTML = `
             <input type="checkbox" ${state.selectedItemKeys.has(item.item_key) ? "checked" : ""} />
-            <div>
-              <strong>${item.title}</strong>
-              <div class="meta">${item.item_key} · ${item.year || "-"} · ${item.item_type || "-"}</div>
+            <div class="item-row-body">
+              <button type="button" class="title-button">${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>
           `;
-          row.querySelector("input").addEventListener("change", () => toggleItemSelection(item.item_key));
+          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);
         }
         updateImportActionState();
@@ -784,6 +971,7 @@
       }
 
       async function loadCollectionItems(collectionKey) {
+        cancelAbstractPreview();
         if (!state.collectionItemsLoaded && state.loadingCollectionKey === collectionKey) {
           return;
         }
@@ -809,7 +997,7 @@
         renderCollectionItems();
         setStatus(elements.collectionStatus, "正在加载文献...");
         try {
-          const payload = await api(`/api/zotero/collections/${collectionKey}/items`);
+          const payload = await api(`/api/zotero/collections/${collectionKey}/items?include_descendants=false`);
           if (state.activeCollectionItemsRequestToken !== requestToken || state.selectedCollectionKey !== collectionKey) {
             return;
           }
@@ -820,7 +1008,7 @@
           const visibleCount = state.visibleCollectionItems.length;
           setStatus(
             elements.collectionStatus,
-            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。"
+            visibleCount ? `当前目录共 ${visibleCount} 篇文献。` : "当前目录下没有可导入文献。"
           );
         } catch (error) {
           if (state.activeCollectionItemsRequestToken === requestToken) {
@@ -832,6 +1020,7 @@
       }
 
       function toggleItemSelection(itemKey) {
+        cancelAbstractPreview();
         if (state.selectedItemKeys.has(itemKey)) {
           state.selectedItemKeys.delete(itemKey);
         } else {
@@ -842,16 +1031,8 @@
         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();
@@ -859,6 +1040,7 @@
       }
 
       async function importSelectedItems() {
+        cancelAbstractPreview();
         if (!state.currentProjectId || !state.selectedItemKeys.size) {
           updateImportActionState();
           return;
@@ -882,6 +1064,7 @@
         elements.importModal.hidden = false;
         elements.importModal.setAttribute("aria-hidden", "false");
         document.body.classList.toggle("modal-open", true);
+        cancelAbstractPreview();
         updateImportActionState();
         if (!state.collectionTree.length) {
           try {
@@ -909,6 +1092,7 @@
         elements.importModal.hidden = true;
         elements.importModal.setAttribute("aria-hidden", "true");
         document.body.classList.toggle("modal-open", false);
+        cancelAbstractPreview();
       }
 
       async function loadProjects() {
@@ -979,7 +1163,7 @@
       });
       elements.closeImportModalButton.addEventListener("click", closeImportModal);
       elements.importModalOverlay.addEventListener("click", closeImportModal);
-      elements.selectDescendantsButton.addEventListener("click", selectVisibleItems);
+      elements.collectionItems.addEventListener("scroll", cancelAbstractPreview);
       elements.clearSelectionButton.addEventListener("click", clearSelectedItems);
       elements.importSelectedItemsButton.addEventListener("click", () => {
         importSelectedItems().catch((error) => {