admin ui: make filter-error use theme error tokens

tests/Feature/AdminBaseCssFilterErrorShouldUseThemeErrorTokensTest.php

@@ -0,0 +1,37 @@
+<?php
+
+namespace Tests\Feature;
+
+use Illuminate\Foundation\Testing\RefreshDatabase;
+use Tests\TestCase;
+
+class AdminBaseCssFilterErrorShouldUseThemeErrorTokensTest extends TestCase
+{
+    use RefreshDatabase;
+
+    protected function loginAsPlatformAdmin(): void
+    {
+        $this->seed();
+
+        $this->post('/admin/login', [
+            'email' => 'platform.admin@demo.local',
+            'password' => 'Platform@123456',
+        ])->assertRedirect('/admin');
+    }
+
+    public function test_admin_base_css_filter_error_should_use_theme_error_tokens(): void
+    {
+        $this->loginAsPlatformAdmin();
+
+        $css = file_get_contents(public_path('css/admin-base.css'));
+        $this->assertIsString($css);
+
+        // filter-error 属于错误提示组件，应引用主题错误令牌（便于全站统一风格）
+        $this->assertStringContainsString('.filter-error{', $css);
+        $this->assertStringContainsString('background:var(--adm-error-bg', $css);
+        $this->assertStringContainsString('color:var(--adm-error', $css);
+
+        // 不应再硬编码旧的暗红色文本（#991b1b）
+        $this->assertStringNotContainsString('#991b1b', $css);
+    }
+}