task-241(admin.html观感对齐): 蓝白浅色 token 基线翻转（浅色侧栏+蓝灰主色 #4f78a5）

admin-frontend-vue/src/styles/main.css

@@ -1,13 +1,22 @@
 :root {
-  --admin-sidebar: #192132;
-  --admin-sidebar-deep: #121827;
-  --admin-primary: #6366f1;
-  --admin-primary-soft: #eef0ff;
-  --admin-bg: #f3f5f9;
-  --admin-border: #e5e7ef;
-  --admin-text: #1f2937;
-  --admin-muted: #7b8495;
-  font-family: "Microsoft YaHei", "PingFang SC", "Helvetica Neue", sans-serif;
+  --admin-sidebar: #f8fbfe;
+  --admin-sidebar-deep: #edf3f9;
+  --admin-primary: #4f78a5;
+  --admin-primary-soft: #e7f0f8;
+  --admin-bg: #f4f7fb;
+  --admin-border: #d8e3ee;
+  --admin-text: #24384d;
+  --admin-muted: #5b6f83;
+  font-family: Inter, "SF Pro Display", "Microsoft YaHei", "PingFang SC", "Helvetica Neue", sans-serif;
+  /* Element Plus 主色对齐 admin.html 蓝白浅色皮肤（渐变主键 #5f85ad→#4f78a5） */
+  --el-color-primary: #4f78a5;
+  --el-color-primary-light-3: #7d9abf;
+  --el-color-primary-light-5: #a5bad2;
+  --el-color-primary-light-7: #cddbe6;
+  --el-color-primary-light-8: #e1e9f0;
+  --el-color-primary-light-9: #f0f4f8;
+  --el-color-primary-dark-2: #3f628a;
+  --el-border-radius-base: 6px;
 }
 
 * { box-sizing: border-box; }