diff --git a/src/main/java/com/yunhai/cms/controller/portal/PortalPageRenderer.java b/src/main/java/com/yunhai/cms/controller/portal/PortalPageRenderer.java
index b071ede..ced5540 100644
--- a/src/main/java/com/yunhai/cms/controller/portal/PortalPageRenderer.java
+++ b/src/main/java/com/yunhai/cms/controller/portal/PortalPageRenderer.java
@@ -353,10 +353,14 @@ public class PortalPageRenderer {
         }
     }
 
-    /** 区块公共头：type/title，并合成为 category.name 供主题 fragment 复用（block.category.name 取标题） */
+    /** 区块公共头：type/title，并合成为 category.name 供主题 fragment 复用（block.category.name 取标题）。
+     *  F2（docs/20）：透传区块 id（编辑器实时预览 postMessage 重排的 DOM 锚点 data-plb-id）。 */
     private Map<String, Object> baseBlock(Map<String, Object> spec, String type, String fallbackTitle) {
         Map<String, Object> block = new HashMap<>();
         block.put("type", type);
+        if (spec.get("id") != null) {
+            block.put("id", String.valueOf(spec.get("id")));
+        }
         String title = spec.get("title") == null ? "" : String.valueOf(spec.get("title")).trim();
         if (title.isEmpty()) {
             title = fallbackTitle;
diff --git a/src/main/resources/templates/themes/campus-glow/home.html b/src/main/resources/templates/themes/campus-glow/home.html
index 7bae0f5..4ae4c82 100644
--- a/src/main/resources/templates/themes/campus-glow/home.html
+++ b/src/main/resources/templates/themes/campus-glow/home.html
@@ -30,7 +30,9 @@
          注意坑④：th:replace（优先级 100）先于 th:case（300）执行——case 必须放父元素、replace 放子元素。 -->
     <th:block th:if="${layoutBlocks != null}">
         <th:block th:replace="~{'themes/common/fragments/home-blocks' :: style}" />
+        <th:block th:replace="~{'themes/common/fragments/home-blocks' :: previewScript}" />
         <th:block th:each="block : ${layoutBlocks}">
+            <div class="plb-anchor" th:attr="data-plb-id=${block['id']}" style="display:contents">
             <th:block th:switch="${block.type}">
                 <th:block th:case="'article_list'">
                     <th:block th:switch="${block.homeStyle}">
@@ -48,6 +50,7 @@
                 <th:block th:case="'notice_bar'"><th:block th:replace="~{${themeBase} + '/fragments/home-blocks' :: notice_bar(${block})}" /></th:block>
                 <th:block th:case="*"><th:block th:replace="~{'themes/common/fragments/home-blocks' :: render(${block})}" /></th:block>
             </th:block>
+            </div>
         </th:block>
     </th:block>
 
diff --git a/src/main/resources/templates/themes/common/fragments/home-blocks.html b/src/main/resources/templates/themes/common/fragments/home-blocks.html
index e8c6665..42ad261 100644
--- a/src/main/resources/templates/themes/common/fragments/home-blocks.html
+++ b/src/main/resources/templates/themes/common/fragments/home-blocks.html
@@ -83,11 +83,17 @@
 .plb-notice-warn{background:var(--plb-warn-bg);border-color:var(--plb-warn-border)}
 .plb-notice-warn .plb-notice-tag{color:var(--plb-warn-fg)}
 /* 全宽区块必须跨满整行：网格型主题（mint-breeze 系 .home-main 是三列）会把它们塞进单列，
-   非网格父容器下 grid-column 无副作用，故由骨架自带。 */
+   非网格父容器下 grid-column 无副作用，故由骨架自带。
+   F2（docs/20）：布局区块经 .plb-anchor（display:contents 预览锚点）包裹时按子选择器等效覆盖。 */
 main > .plb-ticker{grid-column:1 / -1}
 main > .plb-newshot{grid-column:1 / -1}
 main > .plb-section{grid-column:1 / -1}
 main > .plb-notice-bar{grid-column:1 / -1}
+main > .plb-anchor{display:contents;grid-column:auto}
+main > .plb-anchor > .plb-ticker{grid-column:1 / -1}
+main > .plb-anchor > .plb-newshot{grid-column:1 / -1}
+main > .plb-anchor > .plb-section{grid-column:1 / -1}
+main > .plb-anchor > .plb-notice-bar{grid-column:1 / -1}
 @media (max-width:768px){
   .plb-grid2{columns:1}
   .plb-imagewall{grid-template-columns:repeat(2,1fr)}
@@ -326,3 +332,49 @@ main > .plb-notice-bar{grid-column:1 / -1}
           th:text="${block['noticeText']}">公告正文</span>
   </div>
 </div>
+
+<!--
+  F2（docs/20）实时预览监听脚本：管理端首页布局编辑器（iframe 加载正式门户）经 postMessage
+  发送未保存的编排模拟——{type:'cms-layout-preview', order:[区块id…], cssVars:{…}}。
+  行为：按 order 重排/隐藏 [data-plb-id] 锚点（display:contents 包裹层，零布局影响）；
+  未知 id（未保存的新区块）静默忽略 → 编辑器侧提供手动刷新兜底（D-3 降级路径）。
+  安全：仅 DOM 移动/显隐与 CSS 变量赋值（textContent/innerHTML 一概不碰），payload 严格校形。
+  引用位置：主题 home.html 布局分支随 :: style 一并引入一次。
+-->
+<th:block th:fragment="previewScript">
+<script>
+(function () {
+  if (window.__cmsLayoutPreviewBound) { return; }
+  window.__cmsLayoutPreviewBound = true;
+  window.addEventListener('message', function (ev) {
+    var data = ev.data;
+    if (!data || data.type !== 'cms-layout-preview') { return; }
+    var anchors = Array.prototype.slice.call(document.querySelectorAll('[data-plb-id]'));
+    if (!anchors.length) { return; }
+    var order = Array.isArray(data.order) ? data.order.filter(function (x) {
+      return typeof x === 'string' && x.length <= 64;
+    }) : null;
+    if (order) {
+      var byId = {};
+      anchors.forEach(function (a) { byId[a.getAttribute('data-plb-id')] = a; });
+      var parent = anchors[0].parentNode;
+      order.forEach(function (id) {
+        var a = byId[id];
+        if (a) { a.style.display = 'contents'; parent.appendChild(a); }
+      });
+      anchors.forEach(function (a) {
+        if (order.indexOf(a.getAttribute('data-plb-id')) < 0) { a.style.display = 'none'; }
+      });
+    }
+    if (data.cssVars && typeof data.cssVars === 'object') {
+      var bad = /[^a-zA-Z0-9-_, .#%()]/;
+      Object.keys(data.cssVars).forEach(function (k) {
+        if (/^--[a-zA-Z][\w-]*$/.test(k) && !bad.test(String(data.cssVars[k]))) {
+          document.documentElement.style.setProperty(k, data.cssVars[k]);
+        }
+      });
+    }
+  });
+})();
+</script>
+</th:block>
diff --git a/src/main/resources/templates/themes/default/home.html b/src/main/resources/templates/themes/default/home.html
index e8d41de..1a90f94 100644
--- a/src/main/resources/templates/themes/default/home.html
+++ b/src/main/resources/templates/themes/default/home.html
@@ -26,8 +26,12 @@
     <!-- 首页布局模式（docs/16 §4.4）：home_layout 落库后按区块序列渲染（common 兜底骨架，本主题不另设形态） -->
     <th:block th:if="${layoutBlocks != null}">
         <th:block th:replace="~{'themes/common/fragments/home-blocks' :: style}" />
+        <th:block th:replace="~{'themes/common/fragments/home-blocks' :: previewScript}" />
+        <!-- F2：data-plb-id 锚点（display:contents）供编辑器实时预览 postMessage 重排 -->
         <th:block th:each="block : ${layoutBlocks}">
-            <th:block th:replace="~{'themes/common/fragments/home-blocks' :: render(${block})}" />
+            <div class="plb-anchor" th:attr="data-plb-id=${block['id']}" style="display:contents">
+                <th:block th:replace="~{'themes/common/fragments/home-blocks' :: render(${block})}" />
+            </div>
         </th:block>
     </th:block>
 
diff --git a/src/main/resources/templates/themes/scholar-blue/home.html b/src/main/resources/templates/themes/scholar-blue/home.html
index 64034fe..fa161e8 100644
--- a/src/main/resources/templates/themes/scholar-blue/home.html
+++ b/src/main/resources/templates/themes/scholar-blue/home.html
@@ -30,7 +30,9 @@
          否则未命中的 case 分支也会求值 fragment 表达式（缺键 Map 访问直接抛错整页 500）。 -->
     <th:block th:if="${layoutBlocks != null}">
         <th:block th:replace="~{'themes/common/fragments/home-blocks' :: style}" />
+        <th:block th:replace="~{'themes/common/fragments/home-blocks' :: previewScript}" />
         <th:block th:each="block : ${layoutBlocks}">
+            <div class="plb-anchor" th:attr="data-plb-id=${block['id']}" style="display:contents">
             <th:block th:switch="${block.type}">
                 <th:block th:case="'article_list'">
                     <th:block th:switch="${block.homeStyle}">
@@ -48,6 +50,7 @@
                 <th:block th:case="'notice_bar'"><th:block th:replace="~{${themeBase} + '/fragments/home-blocks' :: notice_bar(${block})}" /></th:block>
                 <th:block th:case="*"><th:block th:replace="~{'themes/common/fragments/home-blocks' :: render(${block})}" /></th:block>
             </th:block>
+            </div>
         </th:block>
     </th:block>