diff --git a/frontend/src/pages/admin/AnalyticsDashboard.tsx b/frontend/src/pages/admin/AnalyticsDashboard.tsx
index ec50d2d..e187f3e 100644
--- a/frontend/src/pages/admin/AnalyticsDashboard.tsx
+++ b/frontend/src/pages/admin/AnalyticsDashboard.tsx
@@ -418,7 +418,7 @@ export default function AnalyticsDashboard() {
     });
 
     // 1. 预计算每台设备的统计：累计投入、空闲时长、人员排序（按 isWorkday 选偏移/时长）
-    const deviceStats = chunkDevices.map((d, idx) => {
+    const deviceStats = chunkDevices.map((_, idx) => {
       let totalInputHours = 0;
       const personHours: Record<string, number> = {};
       const intervals: [number, number][] = [];
@@ -462,7 +462,8 @@ export default function AnalyticsDashboard() {
     });
 
     // 背景主干高度：所选模式下的总生命周期（严丝合缝，消除自然空闲断层）
-    const leadByMode = chunkDevices.map((d, idx) => {
+    // 🔧 不再伪造 1h：设备该是多长就返回多长（0 也是 0，绝不显示虚假的 1h 兜底）
+    const leadByMode = chunkDevices.map((_, idx) => {
       let maxEnd = 0;
       chunkSeries.forEach((s) => s.data.forEach((t) => {
         if (t[0] === idx) {
@@ -470,7 +471,7 @@ export default function AnalyticsDashboard() {
           if (e > maxEnd) maxEnd = e;
         }
       }));
-      return Math.max(maxEnd, 1);
+      return maxEnd;
     });
 
     return {