diff --git a/.memory/worklog.json b/.memory/worklog.json
index bda3b95..ea14199 100644
--- a/.memory/worklog.json
+++ b/.memory/worklog.json
@@ -1788,6 +1788,13 @@
       "type": "session-heartbeat",
       "message": "Claude 会话活跃 · 最近命令：claude · 4 项未提交变更 · 最近提交：auto-save 2026-05-13 15:22 (~5)",
       "files_changed": 4
+    },
+    {
+      "ts": "2026-05-13T15:28:21+08:00",
+      "type": "commit",
+      "message": "auto-save 2026-05-13 15:28 (~4)",
+      "hash": "ad895f9",
+      "files_changed": 4
     }
   ]
 }
diff --git a/web/app/page.tsx b/web/app/page.tsx
index 69e8fda..dcd5383 100644
--- a/web/app/page.tsx
+++ b/web/app/page.tsx
@@ -317,8 +317,8 @@ export default function Home() {
     <>
       <div className="canvas-bg" />
       <main className="relative h-screen w-screen overflow-hidden flex">
-        {/* 主题切换 — 左下角 */}
-        <div className="absolute bottom-3 left-3 z-30 pointer-events-auto">
+        {/* 主题切换 — 左下角 Controls 上方（错开） */}
+        <div className="absolute z-30 pointer-events-auto" style={{ bottom: 180, left: 12 }}>
           <ThemeToggle />
         </div>
 
diff --git a/web/components/nodes/index.tsx b/web/components/nodes/index.tsx
index ac9149c..07d2e75 100644
--- a/web/components/nodes/index.tsx
+++ b/web/components/nodes/index.tsx
@@ -479,19 +479,25 @@ export function KeyframeNode({ data, selected }: any) {
         )}
       </NodeShell>
 
-      {/* Portal hover 预览 — 固定视口右下角，不遮挡 */}
+      {/* Portal hover 预览 — 缩略图正上方展开（DAG 画布上方空旷） */}
       {mounted && hover && jobId && (() => {
         const hf = frames.find((x) => x.index === hover.idx)
         if (!hf) return null
         const vidAspect = d.job && d.job.height > 0 ? d.job.height / d.job.width : 16 / 9
-        const w = 280
-        const h = w * vidAspect
+        const gap = 12
+        // 高度优先：不超过缩略图上方可用空间，也不超过视口 80vh
+        const maxH = Math.max(160, Math.min(window.innerHeight * 0.8, hover.rect.top - gap - 12))
+        const maxW = Math.min(window.innerWidth * 0.45, 480)
+        let h = maxH, w = h / vidAspect
+        if (w > maxW) { w = maxW; h = w * vidAspect }
+        const centerX = hover.rect.left + hover.rect.width / 2
+        const left = Math.max(12, Math.min(window.innerWidth - w - 12, centerX - w / 2))
+        const top = hover.rect.top - h - gap
         return createPortal(
           <div
             className="fixed z-[120] pointer-events-none"
             style={{
-              right: 20,
-              bottom: 20,
+              left, top,
               animation: "drawer-in 0.18s cubic-bezier(0.32, 0.72, 0, 1)",
             }}
           >
@@ -717,21 +723,26 @@ export function ImageGenNode({ data, selected }: any) {
         )}
       </NodeShell>
 
-      {/* Portal hover 预览 — 固定视口右下角，不遮挡 */}
+      {/* Portal hover 预览 — 缩略图正上方展开 */}
       {mounted && hover && job && (() => {
         const [fi, ei] = hover.key.split("_")
         const frameIdx = parseInt(fi, 10)
         const p = elementCrops.find((x) => x.frameIdx === frameIdx && x.elementId === ei)
         if (!p) return null
         const vidAspect = job.height > 0 ? job.height / job.width : 16 / 9
-        const w = 280
-        const h = w * vidAspect
+        const gap = 12
+        const maxH = Math.max(160, Math.min(window.innerHeight * 0.8, hover.rect.top - gap - 12))
+        const maxW = Math.min(window.innerWidth * 0.45, 480)
+        let h = maxH, w = h / vidAspect
+        if (w > maxW) { w = maxW; h = w * vidAspect }
+        const centerX = hover.rect.left + hover.rect.width / 2
+        const left = Math.max(12, Math.min(window.innerWidth - w - 12, centerX - w / 2))
+        const top = hover.rect.top - h - gap
         return createPortal(
           <div
             className="fixed z-[120] pointer-events-none"
             style={{
-              right: 20,
-              bottom: 20,
+              left, top,
               animation: "drawer-in 0.18s cubic-bezier(0.32, 0.72, 0, 1)",
             }}
           >
diff --git a/web/components/storyboard-bar.tsx b/web/components/storyboard-bar.tsx
index a6fcac3..c83b91c 100644
--- a/web/components/storyboard-bar.tsx
+++ b/web/components/storyboard-bar.tsx
@@ -213,17 +213,23 @@ export function StoryboardBar({ job, selectedFrames, focusedFrame, onFocusFrame,
         </div>
       )}
 
-      {/* Hover 预览 · 固定视口右下角，不遮挡 */}
+      {/* Hover 预览 · 浮在缩略图侧面（右侧优先 / 不够则左侧） */}
       {mounted && hover && (() => {
         const vidAspect = job.height > 0 ? job.height / job.width : 16 / 9
-        const w = 280
+        const w = 320
         const h = w * vidAspect
+        const gap = 16
+        let left = hover.rect.right + gap
+        if (left + w > window.innerWidth - 12) left = hover.rect.left - w - gap
+        if (left < 12) left = 12
+        let top = hover.rect.top + hover.rect.height / 2 - h / 2
+        if (top < 12) top = 12
+        if (top + h > window.innerHeight - 12) top = window.innerHeight - h - 12
         return createPortal(
           <div
             className="fixed z-[120] pointer-events-none"
             style={{
-              right: 20,
-              bottom: 20,
+              left, top,
               animation: "drawer-in 0.18s cubic-bezier(0.32, 0.72, 0, 1)",
             }}
           >