chore(admin-ui): tokenise popover shadow and surface tint

public/css/admin-components.css

@@ -24,7 +24,7 @@
     border-radius:var(--adm-radius, 12px);
     padding:12px 12px;
     color:var(--adm-text, #0f172a);
-    box-shadow:0 12px 30px rgba(15, 23, 42, .12);
+    box-shadow:var(--adm-shadow-popover, 0 12px 30px rgba(15, 23, 42, .12));
     display:flex;
     align-items:flex-start;
     justify-content:space-between;
@@ -250,7 +250,7 @@
 .list-card-table .table-empty{
     padding:24px 12px;
     text-align:center;
-    background:rgba(15, 23, 42, .02);
+    background:var(--adm-surface-tint, rgba(15, 23, 42, .02));
 }
 
 /* 可复用：PageHeader（参考 Ant Design Pro：标题区 + 描述 + 右侧操作区） */
@@ -549,7 +549,7 @@
     border:1px solid var(--adm-border-color, #e5e7eb);
     border-radius:var(--adm-radius, 12px);
     padding:10px;
-    box-shadow:0 12px 30px rgba(15, 23, 42, .12);
+    box-shadow:var(--adm-shadow-popover, 0 12px 30px rgba(15, 23, 42, .12));
     z-index:100;
 }