diff --git a/src/AKSRT/Ai/AI.php b/src/AKSRT/Ai/AI.php
index 8c7efdb8..064f1b75 100644
--- a/src/AKSRT/Ai/AI.php
+++ b/src/AKSRT/Ai/AI.php
@@ -282,7 +282,7 @@ class AI {
                 'success' => true,
                 'content' => $text,
             ];
-        } catch (Throwable $t) {
+        } catch (\Throwable $t) {
             return [
                 'success' => false,
                 'message' => $t->getMessage() ?: __('WordPress AI Client 调用失败', 'aksrt'),
diff --git a/src/AKSRT/Auth/Moderation.php b/src/AKSRT/Auth/Moderation.php
index 2aa5abd9..69bfd53e 100644
--- a/src/AKSRT/Auth/Moderation.php
+++ b/src/AKSRT/Auth/Moderation.php
@@ -228,7 +228,7 @@ class Moderation {
 
             $decision = $this->enrich_moderation_result($decision, $commentdata);
             $this->remember_result($commentdata, $decision);
-        } catch (Exception $e) {
+        } catch (\Exception $e) {
             // Intentionally silent: keep moderation flow without writing runtime logs.
         }
 
diff --git a/src/AKSRT/Content/Download.php b/src/AKSRT/Content/Download.php
index 2ce960d6..47e69485 100644
--- a/src/AKSRT/Content/Download.php
+++ b/src/AKSRT/Content/Download.php
@@ -37,7 +37,7 @@ class Download {
 
     public function maybe_schedule_cleanup(): void {
         if (!wp_next_scheduled('aksrt_dl_token_cleanup')) {
-            $next = (new DateTimeImmutable('tomorrow 03:30', wp_timezone()))->getTimestamp();
+            $next = (new \DateTimeImmutable('tomorrow 03:30', wp_timezone()))->getTimestamp();
             wp_schedule_event($next, 'daily', 'aksrt_dl_token_cleanup');
         }
     }
@@ -49,8 +49,8 @@ class Download {
         $table = \AKSRT\Core\DBMigrator::table('dl_token');
         if (!$table) return;
 
-        $now_utc = (new DateTimeImmutable('now', new DateTimeZone('UTC')))->format('Y-m-d H:i:s');
-        $audit_cutoff = (new DateTimeImmutable('-7 days', new DateTimeZone('UTC')))->format('Y-m-d H:i:s');
+        $now_utc = (new \DateTimeImmutable('now', new \DateTimeZone('UTC')))->format('Y-m-d H:i:s');
+        $audit_cutoff = (new \DateTimeImmutable('-7 days', new \DateTimeZone('UTC')))->format('Y-m-d H:i:s');
 
         $wpdb->query($wpdb->prepare(
             "DELETE FROM {$table} WHERE expires_at < %s",
@@ -417,8 +417,8 @@ class Download {
         $ip = function_exists('aksrt_get_client_ip') ? (string) aksrt_get_client_ip() : (string) ($_SERVER['REMOTE_ADDR'] ?? '');
         $ua_hash = sha1((string) ($_SERVER['HTTP_USER_AGENT'] ?? ''));
 
-        $now_utc = (new DateTimeImmutable('now', new DateTimeZone('UTC')))->format('Y-m-d H:i:s');
-        $expires_utc = (new DateTimeImmutable('now', new DateTimeZone('UTC')))->modify('+' . self::TOKEN_TTL . ' seconds')->format('Y-m-d H:i:s');
+        $now_utc = (new \DateTimeImmutable('now', new \DateTimeZone('UTC')))->format('Y-m-d H:i:s');
+        $expires_utc = (new \DateTimeImmutable('now', new \DateTimeZone('UTC')))->modify('+' . self::TOKEN_TTL . ' seconds')->format('Y-m-d H:i:s');
 
         $ok = $wpdb->insert(
             $table,
diff --git a/src/AKSRT/Credits/Earn.php b/src/AKSRT/Credits/Earn.php
index 3eaea3a2..848606ee 100644
--- a/src/AKSRT/Credits/Earn.php
+++ b/src/AKSRT/Credits/Earn.php
@@ -57,7 +57,7 @@ class Earn {
 		if ($user_id <= 0 || !class_exists('PointsFree')) {
 			return;
 		}
-		$today = (new DateTimeImmutable('today', wp_timezone()))->format('Y-m-d');
+		$today = (new \DateTimeImmutable('today', wp_timezone()))->format('Y-m-d');
 		$last  = (string) get_user_meta($user_id, PointsFree::META_LOGIN, true);
 		if ($last === $today) {
 			return;
diff --git a/src/AKSRT/Credits/Invite.php b/src/AKSRT/Credits/Invite.php
index 5277e855..53e2f400 100644
--- a/src/AKSRT/Credits/Invite.php
+++ b/src/AKSRT/Credits/Invite.php
@@ -238,7 +238,7 @@ class Invite {
         $log_table = \AKSRT\Core\DBMigrator::table('credit_log');
         if (!$log_table) return true;
 
-        $today_utc = (new DateTimeImmutable('today', wp_timezone()))->setTimezone(new DateTimeZone('UTC'))->format('Y-m-d H:i:s');
+        $today_utc = (new \DateTimeImmutable('today', wp_timezone()))->setTimezone(new \DateTimeZone('UTC'))->format('Y-m-d H:i:s');
         $count = (int) $wpdb->get_var($wpdb->prepare(
             "SELECT COUNT(*) FROM {$log_table} WHERE reason = 'invite' AND ip = %s AND created_at >= %s",
             $ip,
diff --git a/src/AKSRT/Credits/PointsFree.php b/src/AKSRT/Credits/PointsFree.php
index d2310064..71b9748d 100644
--- a/src/AKSRT/Credits/PointsFree.php
+++ b/src/AKSRT/Credits/PointsFree.php
@@ -269,7 +269,7 @@ class PointsFree {
 	}
 
 	private static function today_key(): string {
-		return (new DateTimeImmutable('today', wp_timezone()))->format('Y-m-d');
+		return (new \DateTimeImmutable('today', wp_timezone()))->format('Y-m-d');
 	}
 
 	/**
diff --git a/src/AKSRT/Credits/Signin.php b/src/AKSRT/Credits/Signin.php
index 6fb14555..58cd1a86 100644
--- a/src/AKSRT/Credits/Signin.php
+++ b/src/AKSRT/Credits/Signin.php
@@ -153,7 +153,7 @@ class Signin {
 
     /** 站点时区下的今日日期 'Y-m-d' */
     private function today_date(): string {
-        return (new DateTimeImmutable('today', wp_timezone()))->format('Y-m-d');
+        return (new \DateTimeImmutable('today', wp_timezone()))->format('Y-m-d');
     }
 
     /** 取签到记录 */
@@ -181,7 +181,7 @@ class Signin {
         $table = \AKSRT\Core\DBMigrator::table('signin_log');
         if (!$table) return [];
 
-        $from_date = (new DateTimeImmutable("-{$days} days", wp_timezone()))->format('Y-m-d');
+        $from_date = (new \DateTimeImmutable("-{$days} days", wp_timezone()))->format('Y-m-d');
 
         $rows = $wpdb->get_results($wpdb->prepare(
             "SELECT signin_date FROM {$table} WHERE user_id = %d AND signin_date >= %s ORDER BY signin_date ASC",
@@ -209,19 +209,19 @@ class Signin {
         if (empty($rows)) return 0;
 
         $dates = array_map(fn($r) => $r['signin_date'], $rows);
-        $today = new DateTimeImmutable($today_str);
+        $today = new \DateTimeImmutable($today_str);
         $tz = wp_timezone();
 
         // 起点：若今天已签则从今天回看，否则从昨天回看
         $cursor = in_array($today_str, $dates, true)
             ? $today
-            : $today->sub(new DateInterval('P1D'));
+            : $today->sub(new \DateInterval('P1D'));
 
         $count = 0;
         foreach ($dates as $d) {
             if ($d === $cursor->format('Y-m-d')) {
                 $count++;
-                $cursor = $cursor->sub(new DateInterval('P1D'));
+                $cursor = $cursor->sub(new \DateInterval('P1D'));
             } else {
                 break;
             }