diff --git a/backend/crates/gateway-admin/src/backup/task.rs b/backend/crates/gateway-admin/src/backup/task.rs
index 34ae8eaf7..3fbbfdf85 100644
--- a/backend/crates/gateway-admin/src/backup/task.rs
+++ b/backend/crates/gateway-admin/src/backup/task.rs
@@ -487,12 +487,35 @@ impl BackupTask {
                     );
                 }
             }
-            Ok(_) => {
+            Ok(Some(remote)) => {
+                let size_matches = remote.size_bytes == size_bytes;
+                let sha256_matches = remote.sha256 == sha256;
+                warn!(
+                    backup_id = %record.id,
+                    expected_size_bytes = size_bytes,
+                    remote_size_bytes = remote.size_bytes,
+                    sha256_matches,
+                    "备份远端对象校验不一致"
+                );
                 let _ = store.delete_object(&config, &record.object_key).await;
                 self.fail_task(
                     record,
                     code::REMOTE_VERIFICATION_FAILED,
-                    "远端对象大小或校验值不一致",
+                    match (size_matches, sha256_matches) {
+                        (false, true) => "远端对象大小不一致",
+                        (true, false) => "远端对象 sha256 校验值不一致",
+                        (false, false) => "远端对象大小和 sha256 校验值均不一致",
+                        (true, true) => "远端对象校验状态异常",
+                    },
+                )
+                .await?;
+            }
+            Ok(None) => {
+                warn!(backup_id = %record.id, "上传完成后未找到远端对象");
+                self.fail_task(
+                    record,
+                    code::REMOTE_VERIFICATION_FAILED,
+                    "上传完成后未找到远端对象",
                 )
                 .await?;
             }
@@ -516,10 +539,17 @@ impl BackupTask {
         error_code: &'static str,
         message: impl Into<String>,
     ) -> Result<(), WorkerTaskError> {
+        let message = message.into();
+        warn!(
+            backup_id = %record.id,
+            error_code,
+            error_message = %message,
+            "备份任务失败"
+        );
         let now = Utc::now();
         let update = StatusTransitionUpdate {
             error_code: Some(error_code.to_string()),
-            error_message: Some(message.into()),
+            error_message: Some(message),
             completed_at: Some(now),
             ..Default::default()
         };
diff --git a/backend/crates/gateway-store/Cargo.toml b/backend/crates/gateway-store/Cargo.toml
index b57de36e5..44fdf4fad 100644
--- a/backend/crates/gateway-store/Cargo.toml
+++ b/backend/crates/gateway-store/Cargo.toml
@@ -37,7 +37,7 @@ uuid = { version = "1.23.3", features = ["v4", "v7"] }
 
 [dev-dependencies]
 tempfile = "3.23"
-tokio = { version = "1.52.3", default-features = false, features = ["macros", "rt-multi-thread", "fs", "io-util", "process", "time"] }
+tokio = { version = "1.52.3", default-features = false, features = ["macros", "rt-multi-thread", "fs", "io-util", "net", "process", "time"] }
 
 [lints]
 workspace = true
diff --git a/backend/crates/gateway-store/src/backup/s3.rs b/backend/crates/gateway-store/src/backup/s3.rs
index e742ee8d0..26433cded 100644
--- a/backend/crates/gateway-store/src/backup/s3.rs
+++ b/backend/crates/gateway-store/src/backup/s3.rs
@@ -385,7 +385,13 @@ async fn upload_parts(
                     BackupError::new(code::S3_UPLOAD_FAILED, "上传并发闸门关闭".to_owned())
                 })?;
                 let offset = (part - 1) * (PART_SIZE as u64);
-                let bytes = read_part(&source, offset, PART_SIZE).await?;
+                let remaining = file_size.checked_sub(offset).ok_or_else(|| {
+                    BackupError::new(code::S3_UPLOAD_FAILED, "分片偏移超出归档大小".to_owned())
+                })?;
+                let part_len = usize::try_from(remaining.min(PART_SIZE as u64)).map_err(|_| {
+                    BackupError::new(code::S3_UPLOAD_FAILED, "分片大小溢出".to_owned())
+                })?;
+                let bytes = read_part(&source, offset, part_len).await?;
                 let part_number = i32::try_from(part).map_err(|_| {
                     BackupError::new(code::S3_UPLOAD_FAILED, "分片号溢出".to_owned())
                 })?;
@@ -450,20 +456,19 @@ async fn upload_parts(
         .map_err(map_s3_error)
 }
 
-/// 从文件中读取一个分片（最多 `PART_SIZE` 字节）。
-async fn read_part(source: &Path, offset: u64, max_len: usize) -> Result<Vec<u8>, BackupError> {
+/// 从文件中读取指定长度的完整分片。
+async fn read_part(source: &Path, offset: u64, len: usize) -> Result<Vec<u8>, BackupError> {
     let mut file = tokio::fs::File::open(source)
         .await
         .map_err(|_| BackupError::new(code::S3_UPLOAD_FAILED, "打开暂存归档失败".to_owned()))?;
     file.seek(SeekFrom::Start(offset))
         .await
         .map_err(|_| BackupError::new(code::S3_UPLOAD_FAILED, "定位暂存归档失败".to_owned()))?;
-    let mut buffer = vec![0_u8; max_len];
-    let n = file
-        .read(&mut buffer)
+    let mut buffer = vec![0_u8; len];
+    // Tokio 默认单次文件读取最多 2 MiB；分片必须读取完整，不能把短读当作末尾分片上传。
+    file.read_exact(&mut buffer)
         .await
         .map_err(|_| BackupError::new(code::S3_UPLOAD_FAILED, "读取暂存归档失败".to_owned()))?;
-    buffer.truncate(n);
     Ok(buffer)
 }
 
diff --git a/backend/crates/gateway-store/tests/main.rs b/backend/crates/gateway-store/tests/main.rs
index 3ec752bac..6ff8065c4 100644
--- a/backend/crates/gateway-store/tests/main.rs
+++ b/backend/crates/gateway-store/tests/main.rs
@@ -1,3 +1,4 @@
 mod postgres;
 mod redis;
+mod s3;
 mod support;
diff --git a/backend/crates/gateway-store/tests/s3.rs b/backend/crates/gateway-store/tests/s3.rs
new file mode 100644
index 000000000..8805b2088
--- /dev/null
+++ b/backend/crates/gateway-store/tests/s3.rs
@@ -0,0 +1,141 @@
+use std::io;
+
+use chrono::Utc;
+use gateway_admin::model::backup::{BackupObjectMetadata, BackupStorageConfig};
+use gateway_admin::ports::backup::{BackupObjectStorePort, UploadObjectRequest};
+use gateway_core::engine::CancellationToken;
+use gateway_store::backup::s3::S3ObjectStoreAdapter;
+use secrecy::SecretString;
+use tokio::io::{AsyncReadExt as _, AsyncWriteExt as _};
+use tokio::net::{TcpListener, TcpStream};
+
+const PART_SIZE_ABOVE_TOKIO_DEFAULT: usize = 2 * 1024 * 1024 + 1;
+
+#[tokio::test]
+async fn upload_file_sends_full_part_beyond_tokio_default_buffer_limit() {
+    let directory = tempfile::tempdir().expect("create temporary directory");
+    let source = directory.path().join("archive.dump");
+    let expected = vec![b'x'; PART_SIZE_ABOVE_TOKIO_DEFAULT];
+    tokio::fs::write(&source, &expected)
+        .await
+        .expect("write temporary archive");
+
+    let listener = TcpListener::bind("127.0.0.1:0")
+        .await
+        .expect("bind multipart probe server");
+    let endpoint = format!(
+        "http://{}",
+        listener.local_addr().expect("read listener address")
+    );
+    let server = tokio::spawn(serve_multipart_probe(listener));
+    let storage = BackupStorageConfig {
+        storage_revision: 1,
+        endpoint,
+        region: "auto".to_owned(),
+        bucket: "backup-bucket".to_owned(),
+        access_key_id: "test-access-key".to_owned(),
+        secret_access_key: SecretString::from("test-secret-key"),
+        prefix: "backups".to_owned(),
+        force_path_style: true,
+    };
+    let request = UploadObjectRequest {
+        object_key: "backups/archive.dump".to_owned(),
+        source,
+        metadata: BackupObjectMetadata::new(
+            "backup_test".to_owned(),
+            "a".repeat(64),
+            Utc::now(),
+            PART_SIZE_ABOVE_TOKIO_DEFAULT as u64,
+        ),
+        cancellation: CancellationToken::new(),
+    };
+
+    S3ObjectStoreAdapter::new()
+        .upload_file(&storage, request)
+        .await
+        .expect("upload multipart archive");
+    let uploaded_len = server
+        .await
+        .expect("multipart probe task did not panic")
+        .expect("serve multipart probe");
+
+    assert_eq!(uploaded_len, PART_SIZE_ABOVE_TOKIO_DEFAULT);
+}
+
+async fn serve_multipart_probe(listener: TcpListener) -> io::Result<usize> {
+    let mut uploaded_len = None;
+    for _ in 0..3 {
+        let (mut stream, _) = listener.accept().await?;
+        let (request, body) = read_http_request(&mut stream).await?;
+        let response = if request.starts_with("POST ") && request.contains("uploads") {
+            xml_response(
+                "<InitiateMultipartUploadResult xmlns=\"http://s3.amazonaws.com/doc/2006-03-01/\"><UploadId>probe-upload</UploadId></InitiateMultipartUploadResult>",
+            )
+        } else if request.starts_with("PUT ") && request.contains("partNumber=") {
+            uploaded_len = Some(body.len());
+            "HTTP/1.1 200 OK\r\ncontent-length: 0\r\nconnection: close\r\netag: \"probe-part\"\r\n\r\n".to_owned()
+        } else if request.starts_with("POST ") && request.contains("uploadId=") {
+            xml_response(
+                "<CompleteMultipartUploadResult xmlns=\"http://s3.amazonaws.com/doc/2006-03-01/\"><ETag>\"probe-part\"</ETag></CompleteMultipartUploadResult>",
+            )
+        } else {
+            return Err(io::Error::other("unexpected multipart probe request"));
+        };
+        stream.write_all(response.as_bytes()).await?;
+        stream.shutdown().await?;
+    }
+    uploaded_len.ok_or_else(|| io::Error::other("multipart probe did not receive an upload part"))
+}
+
+async fn read_http_request(stream: &mut TcpStream) -> io::Result<(String, Vec<u8>)> {
+    let mut bytes = Vec::new();
+    let header_end = loop {
+        if let Some(position) = bytes.windows(4).position(|window| window == b"\r\n\r\n") {
+            break position + 4;
+        }
+        let mut chunk = [0_u8; 8 * 1024];
+        let read = stream.read(&mut chunk).await?;
+        if read == 0 {
+            return Err(io::Error::new(
+                io::ErrorKind::UnexpectedEof,
+                "multipart probe request ended before headers",
+            ));
+        }
+        bytes.extend_from_slice(&chunk[..read]);
+    };
+    let headers = String::from_utf8_lossy(&bytes[..header_end]).into_owned();
+    let content_len = headers
+        .lines()
+        .filter_map(|line| line.split_once(':'))
+        .find(|(name, _)| name.eq_ignore_ascii_case("content-length"))
+        .and_then(|(_, value)| value.trim().parse::<usize>().ok())
+        .unwrap_or_default();
+    if headers
+        .to_ascii_lowercase()
+        .contains("expect: 100-continue")
+    {
+        stream.write_all(b"HTTP/1.1 100 Continue\r\n\r\n").await?;
+    }
+    while bytes.len() < header_end + content_len {
+        let mut chunk = [0_u8; 8 * 1024];
+        let read = stream.read(&mut chunk).await?;
+        if read == 0 {
+            return Err(io::Error::new(
+                io::ErrorKind::UnexpectedEof,
+                "multipart probe request ended before body",
+            ));
+        }
+        bytes.extend_from_slice(&chunk[..read]);
+    }
+    Ok((
+        headers,
+        bytes[header_end..header_end + content_len].to_vec(),
+    ))
+}
+
+fn xml_response(body: &str) -> String {
+    format!(
+        "HTTP/1.1 200 OK\r\ncontent-type: application/xml\r\ncontent-length: {}\r\nconnection: close\r\n\r\n{body}",
+        body.len()
+    )
+}
diff --git a/frontend/src/components/base/BaseButton.vue b/frontend/src/components/base/BaseButton.vue
index 10d983434..5dcb98dec 100644
--- a/frontend/src/components/base/BaseButton.vue
+++ b/frontend/src/components/base/BaseButton.vue
@@ -110,10 +110,13 @@ const labelClasses = computed(() => [
   >
     <span
       v-if="loading"
-      class="inline-flex shrink-0 animate-spin origin-center will-change-transform"
+      class="inline-flex shrink-0 items-center justify-center leading-none"
       aria-hidden="true"
     >
-      <LoaderCircle :size="loadingIconSize[size]" />
+      <LoaderCircle
+        :size="loadingIconSize[size]"
+        class="block animate-spin origin-center will-change-transform transform-fill"
+      />
     </span>
     <span v-if="$slots.icon && !loading" class="inline-flex shrink-0">
       <slot name="icon" />
diff --git a/frontend/src/views/accounts/components/AccountStatusBadge.vue b/frontend/src/views/accounts/components/AccountStatusBadge.vue
index 36779b71e..30d39342a 100644
--- a/frontend/src/views/accounts/components/AccountStatusBadge.vue
+++ b/frontend/src/views/accounts/components/AccountStatusBadge.vue
@@ -26,31 +26,31 @@ const statusStyles = {
   success: {
     text: 'text-(--cp-success-text)',
     dot: 'bg-(--cp-success)',
-    badge: 'border-(--cp-success-border) bg-(--cp-success-bg) text-(--cp-success-text)',
-    icon: 'bg-(--cp-success-bg) text-(--cp-success-text) shadow-[inset_0_0_0_1px_var(--cp-success-border)]',
+    badge: 'bg-(--cp-success-bg) text-(--cp-success-text)',
+    icon: 'bg-(--cp-success-bg) text-(--cp-success-text)',
   },
   danger: {
     text: 'text-(--cp-danger-text)',
     dot: 'bg-(--cp-danger)',
-    badge: 'border-(--cp-danger-border) bg-(--cp-danger-bg) text-(--cp-danger-text)',
-    icon: 'bg-(--cp-danger-bg) text-(--cp-danger-text) shadow-[inset_0_0_0_1px_var(--cp-danger-border)]',
+    badge: 'bg-(--cp-danger-bg) text-(--cp-danger-text)',
+    icon: 'bg-(--cp-danger-bg) text-(--cp-danger-text)',
   },
   warning: {
     text: 'text-(--cp-warning-text)',
     dot: 'bg-(--cp-warning)',
-    badge: 'border-(--cp-warning-border) bg-(--cp-warning-bg) text-(--cp-warning-text)',
-    icon: 'bg-(--cp-warning-bg) text-(--cp-warning-text) shadow-[inset_0_0_0_1px_var(--cp-warning-border)]',
+    badge: 'bg-(--cp-warning-bg) text-(--cp-warning-text)',
+    icon: 'bg-(--cp-warning-bg) text-(--cp-warning-text)',
   },
   info: {
     text: 'text-(--cp-info-text)',
     dot: 'bg-(--cp-info)',
-    badge: 'border-(--cp-info-border) bg-(--cp-info-bg) text-(--cp-info-text)',
-    icon: 'bg-(--cp-info-bg) text-(--cp-info-text) shadow-[inset_0_0_0_1px_var(--cp-info-border)]',
+    badge: 'bg-(--cp-info-bg) text-(--cp-info-text)',
+    icon: 'bg-(--cp-info-bg) text-(--cp-info-text)',
   },
   normal: {
     text: 'text-(--cp-text-secondary)',
     dot: 'bg-(--cp-text-muted)',
-    badge: 'border-(--cp-divider-subtle) bg-(--cp-bg-subtle) text-(--cp-text-secondary)',
+    badge: 'bg-(--cp-bg-subtle) text-(--cp-text-secondary)',
     icon: 'bg-(--cp-bg-subtle) text-(--cp-text-secondary)',
   },
 } as const
@@ -165,7 +165,7 @@ const cardIcon = computed(() => {
     </template>
 
     <section class="overflow-hidden rounded-(--cp-popover-radius)">
-      <header class="flex items-start gap-3 border-b border-(--cp-divider-subtle) bg-(--cp-bg-subtle) px-4 py-3">
+      <header class="flex items-start gap-3 bg-(--cp-bg-subtle) px-4 py-3">
         <span
           aria-hidden="true"
           class="inline-flex size-9 shrink-0 items-center justify-center rounded-(--cp-icon-button-radius)"
@@ -184,7 +184,7 @@ const cardIcon = computed(() => {
         </div>
 
         <span
-          class="inline-flex h-5 shrink-0 items-center rounded-full border px-2 text-[10px] leading-none font-heavy"
+          class="inline-flex h-5 shrink-0 items-center rounded-full px-2 text-[10px] leading-none font-heavy"
           :class="statusStyle.badge"
         >
           {{ label }}
@@ -206,7 +206,7 @@ const cardIcon = computed(() => {
           </span>
         </div>
 
-        <div class="rounded-(--cp-input-radius-base) border border-(--cp-divider-subtle) bg-(--cp-bg-surface) px-3 py-2.5">
+        <div class="rounded-(--cp-input-radius-base) bg-(--cp-bg-subtle) px-3 py-2.5">
           <p class="m-0 text-[11px] leading-none font-heavy text-(--cp-text-tertiary)">
             建议操作
           </p>
@@ -217,13 +217,13 @@ const cardIcon = computed(() => {
 
         <div
           v-if="errorText"
-          class="overflow-hidden rounded-(--cp-input-radius-base) border border-(--cp-divider-subtle) bg-(--cp-bg-subtle)"
+          class="overflow-hidden rounded-(--cp-input-radius-base) bg-(--cp-bg-muted)"
         >
-          <div class="flex items-center justify-between gap-3 border-b border-(--cp-divider-subtle) px-3 py-2">
+          <div class="flex items-center justify-between gap-3 px-3 pt-2.5 pb-1.5">
             <span class="text-[11px] leading-none font-heavy text-(--cp-text-tertiary)">上游原始反馈</span>
             <span class="shrink-0 text-[10px] leading-none font-emphasis text-(--cp-text-muted)">仅供排查</span>
           </div>
-          <BaseScrollbar max-height="124px" view-class="px-3 py-2 pr-2">
+          <BaseScrollbar class="bg-(--cp-bg-subtle)" max-height="124px" view-class="px-3 py-2 pr-2">
             <pre class="m-0 whitespace-pre-wrap wrap-break-word font-mono text-[11px] leading-[1.55] font-emphasis text-(--cp-text-secondary)">{{ errorText }}</pre>
           </BaseScrollbar>
         </div>
diff --git a/frontend/src/views/usage/components/UsageRecordDetailModal.vue b/frontend/src/views/usage/components/UsageRecordDetailModal.vue
index d560e908b..11c891d3e 100644
--- a/frontend/src/views/usage/components/UsageRecordDetailModal.vue
+++ b/frontend/src/views/usage/components/UsageRecordDetailModal.vue
@@ -409,16 +409,17 @@ const tokenDonutOption = computed<EChartsOption>(() => {
             尝试链路
           </h3>
           <span
-            class="rounded-full bg-(--cp-bg-muted) px-2 py-0.5 text-[11px] leading-none font-emphasis text-(--cp-text-secondary)"
+            class="text-[11px] leading-none font-emphasis text-(--cp-text-muted)"
             title="中间尝试可能有缺口，仅展示可观测到的记录"
           >
             尽力观测
           </span>
         </div>
         <BaseTable
-          class="mt-3 min-w-0 font-sans"
+          class="attempt-table mt-2.5 min-w-0 font-mono tabular-nums"
           :columns="attemptColumns"
           :rows="attemptRows"
+          :stripe="false"
           compact
           row-key="id"
           min-width="640px"
@@ -478,3 +479,18 @@ const tokenDonutOption = computed<EChartsOption>(() => {
     </template>
   </BaseModal>
 </template>
+
+<style scoped>
+.attempt-table :deep(thead th) {
+  background-color: transparent;
+  box-shadow: none;
+}
+
+.attempt-table :deep(tbody tr) {
+  background-color: transparent;
+}
+
+.attempt-table :deep(tbody td) {
+  background-color: var(--cp-bg-muted);
+}
+</style>