Fix admin loading spinner and empty drive copy

src/admin/DrivesPage.tsx

@@ -708,7 +708,7 @@ export function DrivesPage() {
         </div>
       ) : list.length === 0 ? (
         <div className="admin-card admin-empty">
-          还没有配置任何网盘。点击右上角「新建」，选择夸克 / 115 / PikPak / 沃盘 / OneDrive / 本地存储，填入凭证或路径即可。
+          当前还没有配置任何网盘
         </div>
       ) : (
         <div className="admin-drives-grid">

src/styles/admin.css

@@ -147,6 +147,9 @@
 
 .admin-sidebar__check-update:disabled svg {
   animation: admin-update-spin 0.9s linear infinite;
+  transform-box: fill-box;
+  transform-origin: center;
+  will-change: transform;
 }
 
 @keyframes admin-update-spin {
@@ -1115,6 +1118,16 @@
 
 .admin-spin {
   animation: admin-update-spin 0.9s linear infinite;
+  transform-box: fill-box;
+  transform-origin: center;
+  will-change: transform;
+}
+
+@media (prefers-reduced-motion: reduce) {
+  .admin-sidebar__check-update:disabled svg,
+  .admin-spin {
+    animation-duration: 0.9s !important;
+  }
 }
 
 .admin-table-checkbox-btn {

tests/adminResponsive.test.ts

@@ -100,6 +100,17 @@ test("admin video bulk actions use semantic theme colors", () => {
   assert.doesNotMatch(bulkBodies, /#ff5b8a|#fff6f9|rgba\(255,\s*91,\s*138/);
 });
 
+test("admin loading spinner rotates around icon center", () => {
+  const spinner = ruleBody(adminCss, ".admin-spin");
+  const reducedMotion = ruleBodyByContains(adminCss, ".admin-sidebar__check-update:disabled svg");
+
+  assert.match(spinner, /animation\s*:\s*admin-update-spin\s+0\.9s\s+linear\s+infinite/);
+  assert.match(spinner, /transform-box\s*:\s*fill-box/);
+  assert.match(spinner, /transform-origin\s*:\s*center/);
+  assert.match(spinner, /will-change\s*:\s*transform/);
+  assert.match(reducedMotion, /animation-duration\s*:\s*0\.9s\s*!important/);
+});
+
 test("mobile video management uses compact theme-aware video cards", () => {
   const css = mobileCss();
   const card = ruleBody(css, ".admin-videos-table:not(.admin-drives-table) tr");