diff --git a/Tiku.Api/Contracts/AssetDtos.cs b/Tiku.Api/Contracts/AssetDtos.cs
new file mode 100644
index 0000000..3326bf1
--- /dev/null
+++ b/Tiku.Api/Contracts/AssetDtos.cs
@@ -0,0 +1,60 @@
+using System.ComponentModel.DataAnnotations;
+using Tiku.Application.Assets;
+
+namespace Tiku.Api.Contracts;
+
+public sealed class AssetQueryDto
+{
+    [StringLength(100)]
+    public string? TenantCode { get; set; }
+
+    public Guid? RegionId { get; set; }
+
+    public Guid? SubjectId { get; set; }
+
+    public Guid? CategoryId { get; set; }
+
+    public Guid? ContentNodeId { get; set; }
+
+    public Guid? QuestionId { get; set; }
+
+    public Guid? AssetId { get; set; }
+
+    [StringLength(50)]
+    public string? AssetType { get; set; }
+
+    [StringLength(100)]
+    public string? Category { get; set; }
+
+    [StringLength(200)]
+    public string? AssetKey { get; set; }
+
+    [StringLength(100)]
+    public string? Keyword { get; set; }
+
+    public bool IncludeLocked { get; set; }
+
+    public bool IncludeInactive { get; set; }
+
+    [Range(1, 500)]
+    public int? Limit { get; set; }
+
+    public AssetFilter ToFilter(Guid tenantId)
+    {
+        return new AssetFilter(
+            tenantId,
+            RegionId,
+            SubjectId,
+            CategoryId,
+            ContentNodeId,
+            QuestionId,
+            AssetId,
+            AssetType,
+            Category,
+            AssetKey,
+            Keyword,
+            IncludeLocked,
+            IncludeInactive,
+            Limit);
+    }
+}
diff --git a/Tiku.Api/Controllers/CatalogController.cs b/Tiku.Api/Controllers/CatalogController.cs
index 26e7f69..98de0ff 100644
--- a/Tiku.Api/Controllers/CatalogController.cs
+++ b/Tiku.Api/Controllers/CatalogController.cs
@@ -1,6 +1,7 @@
 using Microsoft.AspNetCore.Authorization;
 using Microsoft.AspNetCore.Mvc;
 using Microsoft.EntityFrameworkCore;
+using Tiku.Application.Assets;
 using Tiku.Api.Contracts;
 using Tiku.Application.Catalog;
 using Tiku.Application.Content;
@@ -21,6 +22,7 @@ public sealed class CatalogController(
     IContentNavigationQueryService contentNavigationQueryService,
     IQuestionBankQueryService questionBankQueryService,
     IStudyContentQueryService studyContentQueryService,
+    IAssetQueryService assetQueryService,
     ICurrentTenant currentTenant,
     TikuDbContext dbContext) : ControllerBase
 {
@@ -303,6 +305,71 @@ public sealed class CatalogController(
             cancellationToken));
     }
 
+    [HttpGet("content-assets")]
+    [EndpointSummary("查询内容资源")]
+    [ProducesResponseType<CatalogList<ContentAssetCatalogItem>>(StatusCodes.Status200OK)]
+    [ProducesResponseType<ProblemDetails>(StatusCodes.Status404NotFound)]
+    public async Task<ActionResult<CatalogList<ContentAssetCatalogItem>>> GetContentAssets(
+        [FromQuery] AssetQueryDto query,
+        CancellationToken cancellationToken)
+    {
+        return Ok(await assetQueryService.GetContentAssetsAsync(
+            query.ToFilter(await ResolveTenantIdAsync(query, cancellationToken)),
+            cancellationToken));
+    }
+
+    [HttpGet("images")]
+    [EndpointSummary("查询图片资源")]
+    [ProducesResponseType<CatalogList<ImageAssetCatalogItem>>(StatusCodes.Status200OK)]
+    [ProducesResponseType<ProblemDetails>(StatusCodes.Status404NotFound)]
+    public async Task<ActionResult<CatalogList<ImageAssetCatalogItem>>> GetImages(
+        [FromQuery] AssetQueryDto query,
+        CancellationToken cancellationToken)
+    {
+        return Ok(await assetQueryService.GetImagesAsync(
+            query.ToFilter(await ResolveTenantIdAsync(query, cancellationToken)),
+            cancellationToken));
+    }
+
+    [HttpGet("app-assets")]
+    [EndpointSummary("查询应用资源")]
+    [ProducesResponseType<CatalogList<AppAssetCatalogItem>>(StatusCodes.Status200OK)]
+    [ProducesResponseType<ProblemDetails>(StatusCodes.Status404NotFound)]
+    public async Task<ActionResult<CatalogList<AppAssetCatalogItem>>> GetAppAssets(
+        [FromQuery] AssetQueryDto query,
+        CancellationToken cancellationToken)
+    {
+        return Ok(await assetQueryService.GetAppAssetsAsync(
+            query.ToFilter(await ResolveTenantIdAsync(query, cancellationToken)),
+            cancellationToken));
+    }
+
+    [HttpGet("video-explanations")]
+    [EndpointSummary("查询视频讲解")]
+    [ProducesResponseType<CatalogList<VideoExplanationCatalogItem>>(StatusCodes.Status200OK)]
+    [ProducesResponseType<ProblemDetails>(StatusCodes.Status404NotFound)]
+    public async Task<ActionResult<CatalogList<VideoExplanationCatalogItem>>> GetVideoExplanations(
+        [FromQuery] AssetQueryDto query,
+        CancellationToken cancellationToken)
+    {
+        return Ok(await assetQueryService.GetVideoExplanationsAsync(
+            query.ToFilter(await ResolveTenantIdAsync(query, cancellationToken)),
+            cancellationToken));
+    }
+
+    [HttpGet("question-videos")]
+    [EndpointSummary("查询题目关联视频")]
+    [ProducesResponseType<CatalogList<QuestionVideoCatalogItem>>(StatusCodes.Status200OK)]
+    [ProducesResponseType<ProblemDetails>(StatusCodes.Status404NotFound)]
+    public async Task<ActionResult<CatalogList<QuestionVideoCatalogItem>>> GetQuestionVideos(
+        [FromQuery] AssetQueryDto query,
+        CancellationToken cancellationToken)
+    {
+        return Ok(await assetQueryService.GetQuestionVideosAsync(
+            query.ToFilter(await ResolveTenantIdAsync(query, cancellationToken)),
+            cancellationToken));
+    }
+
     private async Task<Guid> ResolveTenantIdAsync(
         CatalogQueryDto query,
         CancellationToken cancellationToken)
@@ -363,6 +430,18 @@ public sealed class CatalogController(
             },
             cancellationToken);
     }
+
+    private Task<Guid> ResolveTenantIdAsync(
+        AssetQueryDto query,
+        CancellationToken cancellationToken)
+    {
+        return ResolveTenantIdAsync(
+            new CatalogQueryDto
+            {
+                TenantCode = query.TenantCode
+            },
+            cancellationToken);
+    }
 }
 
 public sealed class TenantNotFoundException : Exception
diff --git a/Tiku.Application/Assets/AssetQueryModels.cs b/Tiku.Application/Assets/AssetQueryModels.cs
new file mode 100644
index 0000000..3dd58e0
--- /dev/null
+++ b/Tiku.Application/Assets/AssetQueryModels.cs
@@ -0,0 +1,95 @@
+using System.Text.Json;
+using Tiku.Domain.Content;
+
+namespace Tiku.Application.Assets;
+
+public sealed record AssetFilter(
+    Guid TenantId,
+    Guid? RegionId = null,
+    Guid? SubjectId = null,
+    Guid? CategoryId = null,
+    Guid? ContentNodeId = null,
+    Guid? QuestionId = null,
+    Guid? AssetId = null,
+    string? AssetType = null,
+    string? Category = null,
+    string? AssetKey = null,
+    string? Keyword = null,
+    bool IncludeLocked = false,
+    bool IncludeInactive = false,
+    int? Limit = null);
+
+public sealed record ContentAssetCatalogItem(
+    Guid Id,
+    string? LegacyId,
+    Guid? RegionId,
+    Guid? SubjectId,
+    Guid? CategoryId,
+    Guid? ContentNodeId,
+    string? AssetKey,
+    string? Title,
+    string? Category,
+    string? Description,
+    string? FileName,
+    string? CdnUrl,
+    bool IsPublic,
+    ContentAssetType AssetType,
+    AssetStorageProvider StorageProvider,
+    string? Bucket,
+    string? ObjectKey,
+    string? MimeType,
+    long? FileSizeBytes,
+    string? ChecksumSha256,
+    ContentVisibility Visibility,
+    string? PreviewUrl,
+    ContentStatus Status,
+    int Order,
+    AssetUploadStatus UploadStatus,
+    DateTimeOffset? VerifiedAt,
+    AssetPreviewStatus PreviewStatus,
+    AssetSecurityScanStatus SecurityScanStatus,
+    JsonElement Metadata);
+
+public sealed record ImageAssetCatalogItem(
+    Guid Id,
+    string? LegacyId,
+    string? Title,
+    string? Category,
+    string? FileName,
+    bool IsPublic,
+    string? CdnUrl,
+    JsonElement Metadata);
+
+public sealed record AppAssetCatalogItem(
+    Guid Id,
+    string? LegacyId,
+    string AssetKey,
+    string? FileName,
+    string? Description,
+    JsonElement Metadata);
+
+public sealed record VideoExplanationCatalogItem(
+    Guid Id,
+    string? LegacyId,
+    Guid? SubjectId,
+    string Title,
+    string? Description,
+    string? VideoUrl,
+    string? ThumbnailUrl,
+    int? DurationSeconds,
+    JsonElement KnowledgeTags,
+    bool IsGeneral,
+    int? Difficulty,
+    int Order,
+    bool IsActive,
+    JsonElement Metadata);
+
+public sealed record QuestionVideoCatalogItem(
+    Guid Id,
+    string? LegacyId,
+    Guid? QuestionId,
+    Guid? VideoId,
+    QuestionVideoType VideoType,
+    int Order,
+    JsonElement Metadata,
+    VideoExplanationCatalogItem? Video);
diff --git a/Tiku.Application/Assets/IAssetQueryService.cs b/Tiku.Application/Assets/IAssetQueryService.cs
new file mode 100644
index 0000000..52c73d9
--- /dev/null
+++ b/Tiku.Application/Assets/IAssetQueryService.cs
@@ -0,0 +1,26 @@
+using Tiku.Application.Catalog;
+
+namespace Tiku.Application.Assets;
+
+public interface IAssetQueryService
+{
+    Task<CatalogList<ContentAssetCatalogItem>> GetContentAssetsAsync(
+        AssetFilter filter,
+        CancellationToken cancellationToken = default);
+
+    Task<CatalogList<ImageAssetCatalogItem>> GetImagesAsync(
+        AssetFilter filter,
+        CancellationToken cancellationToken = default);
+
+    Task<CatalogList<AppAssetCatalogItem>> GetAppAssetsAsync(
+        AssetFilter filter,
+        CancellationToken cancellationToken = default);
+
+    Task<CatalogList<VideoExplanationCatalogItem>> GetVideoExplanationsAsync(
+        AssetFilter filter,
+        CancellationToken cancellationToken = default);
+
+    Task<CatalogList<QuestionVideoCatalogItem>> GetQuestionVideosAsync(
+        AssetFilter filter,
+        CancellationToken cancellationToken = default);
+}
diff --git a/Tiku.Infrastructure/Assets/AssetQueryService.cs b/Tiku.Infrastructure/Assets/AssetQueryService.cs
new file mode 100644
index 0000000..4f35b43
--- /dev/null
+++ b/Tiku.Infrastructure/Assets/AssetQueryService.cs
@@ -0,0 +1,323 @@
+using Microsoft.EntityFrameworkCore;
+using Tiku.Application.Assets;
+using Tiku.Application.Catalog;
+using Tiku.Domain.Content;
+using Tiku.Infrastructure.Persistence;
+
+namespace Tiku.Infrastructure.Assets;
+
+public sealed class AssetQueryService(TikuDbContext dbContext) : IAssetQueryService
+{
+    private const int DefaultLimit = 100;
+    private const int MaxLimit = 500;
+
+    public async Task<CatalogList<ContentAssetCatalogItem>> GetContentAssetsAsync(
+        AssetFilter filter,
+        CancellationToken cancellationToken = default)
+    {
+        var query = dbContext.ContentAssets
+            .AsNoTracking()
+            .Where(asset => asset.TenantId == filter.TenantId);
+
+        if (!filter.IncludeInactive)
+        {
+            query = query.Where(asset => asset.Status == ContentStatus.Active);
+        }
+
+        if (!filter.IncludeLocked)
+        {
+            query = query.Where(asset => asset.Visibility == ContentVisibility.Public || asset.IsPublic);
+        }
+
+        if (filter.RegionId.HasValue)
+        {
+            query = query.Where(asset => asset.RegionId == filter.RegionId.Value || asset.RegionId == null);
+        }
+
+        if (filter.SubjectId.HasValue)
+        {
+            query = query.Where(asset => asset.SubjectId == filter.SubjectId.Value || asset.SubjectId == null);
+        }
+
+        if (filter.CategoryId.HasValue)
+        {
+            query = query.Where(asset => asset.CategoryId == filter.CategoryId.Value || asset.CategoryId == null);
+        }
+
+        if (filter.ContentNodeId.HasValue)
+        {
+            query = query.Where(asset => asset.ContentNodeId == filter.ContentNodeId.Value || asset.ContentNodeId == null);
+        }
+
+        if (filter.AssetId.HasValue)
+        {
+            query = query.Where(asset => asset.Id == filter.AssetId.Value);
+        }
+
+        if (!string.IsNullOrWhiteSpace(filter.AssetType) &&
+            Enum.TryParse<ContentAssetType>(filter.AssetType, ignoreCase: true, out var assetType))
+        {
+            query = query.Where(asset => asset.AssetType == assetType);
+        }
+
+        if (!string.IsNullOrWhiteSpace(filter.Category))
+        {
+            var category = filter.Category.Trim();
+            query = query.Where(asset => asset.Category == category);
+        }
+
+        if (!string.IsNullOrWhiteSpace(filter.AssetKey))
+        {
+            var assetKey = filter.AssetKey.Trim();
+            query = query.Where(asset => asset.AssetKey == assetKey);
+        }
+
+        if (!string.IsNullOrWhiteSpace(filter.Keyword))
+        {
+            var keyword = filter.Keyword.Trim();
+            query = query.Where(asset =>
+                (asset.Title != null && asset.Title.Contains(keyword)) ||
+                (asset.FileName != null && asset.FileName.Contains(keyword)) ||
+                (asset.Description != null && asset.Description.Contains(keyword)) ||
+                (asset.AssetKey != null && asset.AssetKey.Contains(keyword)));
+        }
+
+        var items = await query
+            .OrderBy(asset => asset.SortOrder)
+            .ThenByDescending(asset => asset.CreatedAt)
+            .Take(ResolveLimit(filter.Limit))
+            .Select(asset => new ContentAssetCatalogItem(
+                asset.Id,
+                asset.LegacyId,
+                asset.RegionId,
+                asset.SubjectId,
+                asset.CategoryId,
+                asset.ContentNodeId,
+                asset.AssetKey,
+                asset.Title,
+                asset.Category,
+                asset.Description,
+                asset.FileName,
+                asset.CdnUrl,
+                asset.IsPublic,
+                asset.AssetType,
+                asset.StorageProvider,
+                asset.Bucket,
+                asset.ObjectKey,
+                asset.MimeType,
+                asset.FileSizeBytes,
+                asset.ChecksumSha256,
+                asset.Visibility,
+                asset.PreviewUrl,
+                asset.Status,
+                asset.SortOrder,
+                asset.UploadStatus,
+                asset.VerifiedAt,
+                asset.PreviewStatus,
+                asset.SecurityScanStatus,
+                asset.Metadata))
+            .ToArrayAsync(cancellationToken);
+
+        return new CatalogList<ContentAssetCatalogItem>(items);
+    }
+
+    public async Task<CatalogList<ImageAssetCatalogItem>> GetImagesAsync(
+        AssetFilter filter,
+        CancellationToken cancellationToken = default)
+    {
+        var query = dbContext.Images
+            .AsNoTracking()
+            .Where(image => image.TenantId == filter.TenantId);
+
+        if (!filter.IncludeLocked)
+        {
+            query = query.Where(image => image.IsPublic);
+        }
+
+        if (!string.IsNullOrWhiteSpace(filter.Category))
+        {
+            var category = filter.Category.Trim();
+            query = query.Where(image => image.Category == category);
+        }
+
+        if (!string.IsNullOrWhiteSpace(filter.Keyword))
+        {
+            var keyword = filter.Keyword.Trim();
+            query = query.Where(image =>
+                (image.Title != null && image.Title.Contains(keyword)) ||
+                (image.FileName != null && image.FileName.Contains(keyword)));
+        }
+
+        var items = await query
+            .OrderBy(image => image.Category)
+            .ThenBy(image => image.Title)
+            .Take(ResolveLimit(filter.Limit))
+            .Select(image => new ImageAssetCatalogItem(
+                image.Id,
+                image.LegacyId,
+                image.Title,
+                image.Category,
+                image.FileName,
+                image.IsPublic,
+                image.CdnUrl,
+                image.Metadata))
+            .ToArrayAsync(cancellationToken);
+
+        return new CatalogList<ImageAssetCatalogItem>(items);
+    }
+
+    public async Task<CatalogList<AppAssetCatalogItem>> GetAppAssetsAsync(
+        AssetFilter filter,
+        CancellationToken cancellationToken = default)
+    {
+        var query = dbContext.AppAssets
+            .AsNoTracking()
+            .Where(asset => asset.TenantId == filter.TenantId);
+
+        if (!string.IsNullOrWhiteSpace(filter.AssetKey))
+        {
+            var assetKey = filter.AssetKey.Trim();
+            query = query.Where(asset => asset.AssetKey == assetKey);
+        }
+
+        if (!string.IsNullOrWhiteSpace(filter.Keyword))
+        {
+            var keyword = filter.Keyword.Trim();
+            query = query.Where(asset =>
+                asset.AssetKey.Contains(keyword) ||
+                (asset.FileName != null && asset.FileName.Contains(keyword)) ||
+                (asset.Description != null && asset.Description.Contains(keyword)));
+        }
+
+        var items = await query
+            .OrderBy(asset => asset.AssetKey)
+            .Take(ResolveLimit(filter.Limit))
+            .Select(asset => new AppAssetCatalogItem(
+                asset.Id,
+                asset.LegacyId,
+                asset.AssetKey,
+                asset.FileName,
+                asset.Description,
+                asset.Metadata))
+            .ToArrayAsync(cancellationToken);
+
+        return new CatalogList<AppAssetCatalogItem>(items);
+    }
+
+    public async Task<CatalogList<VideoExplanationCatalogItem>> GetVideoExplanationsAsync(
+        AssetFilter filter,
+        CancellationToken cancellationToken = default)
+    {
+        var query = dbContext.VideoExplanations
+            .AsNoTracking()
+            .Where(video => video.TenantId == filter.TenantId);
+
+        if (!filter.IncludeInactive)
+        {
+            query = query.Where(video => video.IsActive);
+        }
+
+        if (filter.SubjectId.HasValue)
+        {
+            query = query.Where(video => video.SubjectId == filter.SubjectId.Value || video.SubjectId == null);
+        }
+
+        if (!string.IsNullOrWhiteSpace(filter.Keyword))
+        {
+            var keyword = filter.Keyword.Trim();
+            query = query.Where(video =>
+                video.Title.Contains(keyword) ||
+                (video.Description != null && video.Description.Contains(keyword)));
+        }
+
+        var items = await query
+            .OrderBy(video => video.SortOrder)
+            .ThenBy(video => video.Title)
+            .Take(ResolveLimit(filter.Limit))
+            .Select(video => new VideoExplanationCatalogItem(
+                video.Id,
+                video.LegacyId,
+                video.SubjectId,
+                video.Title,
+                video.Description,
+                video.VideoUrl,
+                video.ThumbnailUrl,
+                video.DurationSeconds,
+                video.KnowledgeTags,
+                video.IsGeneral,
+                video.Difficulty,
+                video.SortOrder,
+                video.IsActive,
+                video.Metadata))
+            .ToArrayAsync(cancellationToken);
+
+        return new CatalogList<VideoExplanationCatalogItem>(items);
+    }
+
+    public async Task<CatalogList<QuestionVideoCatalogItem>> GetQuestionVideosAsync(
+        AssetFilter filter,
+        CancellationToken cancellationToken = default)
+    {
+        var query = dbContext.QuestionVideos
+            .AsNoTracking()
+            .Where(video => video.TenantId == filter.TenantId);
+
+        if (filter.QuestionId.HasValue)
+        {
+            query = query.Where(video => video.QuestionId == filter.QuestionId.Value);
+        }
+
+        if (filter.AssetId.HasValue)
+        {
+            query = query.Where(video => video.VideoId == filter.AssetId.Value);
+        }
+
+        var videoExplanations = dbContext.VideoExplanations.AsNoTracking();
+        var items = await query
+            .OrderBy(video => video.SortOrder)
+            .ThenBy(video => video.CreatedAt)
+            .Take(ResolveLimit(filter.Limit))
+            .GroupJoin(
+                videoExplanations,
+                questionVideo => new { questionVideo.TenantId, Id = questionVideo.VideoId },
+                video => new { video.TenantId, Id = (Guid?)video.Id },
+                (questionVideo, videos) => new
+                {
+                    QuestionVideo = questionVideo,
+                    Video = videos.FirstOrDefault()
+                })
+            .Select(row => new QuestionVideoCatalogItem(
+                row.QuestionVideo.Id,
+                row.QuestionVideo.LegacyId,
+                row.QuestionVideo.QuestionId,
+                row.QuestionVideo.VideoId,
+                row.QuestionVideo.VideoType,
+                row.QuestionVideo.SortOrder,
+                row.QuestionVideo.Metadata,
+                row.Video == null
+                    ? null
+                    : new VideoExplanationCatalogItem(
+                        row.Video.Id,
+                        row.Video.LegacyId,
+                        row.Video.SubjectId,
+                        row.Video.Title,
+                        row.Video.Description,
+                        row.Video.VideoUrl,
+                        row.Video.ThumbnailUrl,
+                        row.Video.DurationSeconds,
+                        row.Video.KnowledgeTags,
+                        row.Video.IsGeneral,
+                        row.Video.Difficulty,
+                        row.Video.SortOrder,
+                        row.Video.IsActive,
+                        row.Video.Metadata)))
+            .ToArrayAsync(cancellationToken);
+
+        return new CatalogList<QuestionVideoCatalogItem>(items);
+    }
+
+    private static int ResolveLimit(int? limit)
+    {
+        return Math.Clamp(limit ?? DefaultLimit, 1, MaxLimit);
+    }
+}
diff --git a/Tiku.Infrastructure/DependencyInjection.cs b/Tiku.Infrastructure/DependencyInjection.cs
index faa47f9..d8b72cd 100644
--- a/Tiku.Infrastructure/DependencyInjection.cs
+++ b/Tiku.Infrastructure/DependencyInjection.cs
@@ -1,12 +1,14 @@
 using Microsoft.EntityFrameworkCore;
 using Microsoft.Extensions.DependencyInjection;
 using Npgsql;
+using Tiku.Application.Assets;
 using Tiku.Application.Auth;
 using Tiku.Application.Catalog;
 using Tiku.Application.Content;
 using Tiku.Application.QuestionBanks;
 using Tiku.Application.Storage;
 using Tiku.Application.StudyContent;
+using Tiku.Infrastructure.Assets;
 using Tiku.Infrastructure.Auth;
 using Tiku.Infrastructure.Catalog;
 using Tiku.Infrastructure.Content;
@@ -42,6 +44,7 @@ public static class DependencyInjection
         services.AddScoped<IContentNavigationQueryService, ContentNavigationQueryService>();
         services.AddScoped<IQuestionBankQueryService, QuestionBankQueryService>();
         services.AddScoped<IStudyContentQueryService, StudyContentQueryService>();
+        services.AddScoped<IAssetQueryService, AssetQueryService>();
         services.AddOptions<AliyunOssOptions>()
             .Validate(
                 AliyunOssOptions.BeValid,
diff --git a/Tiku.IntegrationTests/Api/AssetEndpointTests.cs b/Tiku.IntegrationTests/Api/AssetEndpointTests.cs
new file mode 100644
index 0000000..e33e99f
--- /dev/null
+++ b/Tiku.IntegrationTests/Api/AssetEndpointTests.cs
@@ -0,0 +1,212 @@
+using System.Net;
+using System.Text.Json;
+using Tiku.Domain.Common;
+using Tiku.Domain.Content;
+using Tiku.Domain.Tenancy;
+
+namespace Tiku.IntegrationTests.Api;
+
+public sealed class AssetEndpointTests
+{
+    [Fact]
+    public async Task Content_assets_return_public_active_assets_by_default()
+    {
+        var tenantId = Guid.NewGuid();
+        var regionId = Guid.NewGuid();
+        await using var factory = new ApiTestFactory();
+        await factory.SeedAsync(
+            Tenant(tenantId, "master"),
+            new ContentAsset
+            {
+                Id = Guid.NewGuid(),
+                TenantId = tenantId,
+                RegionId = regionId,
+                Title = "公开讲义",
+                FileName = "handbook.pdf",
+                AssetType = ContentAssetType.Pdf,
+                StorageProvider = AssetStorageProvider.AliyunOss,
+                Bucket = "tiku-assets",
+                ObjectKey = $"{tenantId:N}/handbook.pdf",
+                MimeType = "application/pdf",
+                Visibility = ContentVisibility.Public,
+                Status = ContentStatus.Active,
+                SortOrder = 2
+            },
+            new ContentAsset
+            {
+                Id = Guid.NewGuid(),
+                TenantId = tenantId,
+                RegionId = regionId,
+                Title = "会员讲义",
+                Visibility = ContentVisibility.Members,
+                Status = ContentStatus.Active,
+                SortOrder = 1
+            },
+            new ContentAsset
+            {
+                Id = Guid.NewGuid(),
+                TenantId = tenantId,
+                RegionId = regionId,
+                Title = "归档讲义",
+                Visibility = ContentVisibility.Public,
+                Status = ContentStatus.Archived
+            });
+        using var client = factory.CreateClient();
+
+        using var response = await client.GetAsync($"/api/catalog/content-assets?tenantCode=master&regionId={regionId}&assetType=pdf");
+        var items = await ReadItemsAsync(response);
+
+        Assert.Equal(HttpStatusCode.OK, response.StatusCode);
+        var item = Assert.Single(items);
+        Assert.Equal("公开讲义", item.GetProperty("title").GetString());
+        Assert.Equal("AliyunOss", item.GetProperty("storageProvider").GetString());
+    }
+
+    [Fact]
+    public async Task Content_assets_can_include_locked_catalog_items_when_requested()
+    {
+        var tenantId = Guid.NewGuid();
+        await using var factory = new ApiTestFactory();
+        await factory.SeedAsync(
+            Tenant(tenantId, "master"),
+            new ContentAsset
+            {
+                Id = Guid.NewGuid(),
+                TenantId = tenantId,
+                Title = "会员讲义",
+                Visibility = ContentVisibility.Members,
+                Status = ContentStatus.Active
+            });
+        using var client = factory.CreateClient();
+
+        using var response = await client.GetAsync("/api/catalog/content-assets?tenantCode=master&includeLocked=true");
+        var items = await ReadItemsAsync(response);
+
+        Assert.Equal(HttpStatusCode.OK, response.StatusCode);
+        Assert.Equal("会员讲义", Assert.Single(items).GetProperty("title").GetString());
+    }
+
+    [Fact]
+    public async Task Images_filter_private_items_until_include_locked()
+    {
+        var tenantId = Guid.NewGuid();
+        await using var factory = new ApiTestFactory();
+        await factory.SeedAsync(
+            Tenant(tenantId, "master"),
+            new ImageAsset
+            {
+                Id = Guid.NewGuid(),
+                TenantId = tenantId,
+                Title = "公开图",
+                Category = "banner",
+                IsPublic = true
+            },
+            new ImageAsset
+            {
+                Id = Guid.NewGuid(),
+                TenantId = tenantId,
+                Title = "内部图",
+                Category = "banner",
+                IsPublic = false
+            });
+        using var client = factory.CreateClient();
+
+        using var publicResponse = await client.GetAsync("/api/catalog/images?tenantCode=master&category=banner");
+        using var lockedResponse = await client.GetAsync("/api/catalog/images?tenantCode=master&category=banner&includeLocked=true");
+
+        Assert.Equal(["公开图"], (await ReadItemsAsync(publicResponse)).Select(item => item.GetProperty("title").GetString()!).ToArray());
+        var lockedTitles = (await ReadItemsAsync(lockedResponse))
+            .Select(item => item.GetProperty("title").GetString()!)
+            .ToArray();
+        Assert.Equal(2, lockedTitles.Length);
+        Assert.Contains("内部图", lockedTitles);
+        Assert.Contains("公开图", lockedTitles);
+    }
+
+    [Fact]
+    public async Task App_assets_support_asset_key_lookup()
+    {
+        var tenantId = Guid.NewGuid();
+        await using var factory = new ApiTestFactory();
+        await factory.SeedAsync(
+            Tenant(tenantId, "master"),
+            new AppAsset
+            {
+                Id = Guid.NewGuid(),
+                TenantId = tenantId,
+                AssetKey = "logo",
+                FileName = "logo.png"
+            },
+            new AppAsset
+            {
+                Id = Guid.NewGuid(),
+                TenantId = tenantId,
+                AssetKey = "icon",
+                FileName = "icon.png"
+            });
+        using var client = factory.CreateClient();
+
+        using var response = await client.GetAsync("/api/catalog/app-assets?tenantCode=master&assetKey=logo");
+        var item = Assert.Single(await ReadItemsAsync(response));
+
+        Assert.Equal(HttpStatusCode.OK, response.StatusCode);
+        Assert.Equal("logo", item.GetProperty("assetKey").GetString());
+    }
+
+    [Fact]
+    public async Task Question_videos_include_video_explanation_summary()
+    {
+        var tenantId = Guid.NewGuid();
+        var questionId = Guid.NewGuid();
+        var videoId = Guid.NewGuid();
+        await using var factory = new ApiTestFactory();
+        await factory.SeedAsync(
+            Tenant(tenantId, "master"),
+            new VideoExplanation
+            {
+                Id = videoId,
+                TenantId = tenantId,
+                Title = "解题视频",
+                IsActive = true,
+                SortOrder = 1
+            },
+            new QuestionVideo
+            {
+                Id = Guid.NewGuid(),
+                TenantId = tenantId,
+                QuestionId = questionId,
+                VideoId = videoId,
+                VideoType = QuestionVideoType.Specific
+            });
+        using var client = factory.CreateClient();
+
+        using var response = await client.GetAsync($"/api/catalog/question-videos?tenantCode=master&questionId={questionId}");
+        var item = Assert.Single(await ReadItemsAsync(response));
+
+        Assert.Equal(HttpStatusCode.OK, response.StatusCode);
+        Assert.Equal(questionId, item.GetProperty("questionId").GetGuid());
+        Assert.Equal("解题视频", item.GetProperty("video").GetProperty("title").GetString());
+    }
+
+    private static Tenant Tenant(Guid id, string slug)
+    {
+        return new Tenant
+        {
+            Id = id,
+            Slug = slug,
+            Name = slug,
+            Status = TenantStatus.Active,
+            Metadata = JsonDefaults.Object()
+        };
+    }
+
+    private static async Task<JsonElement[]> ReadItemsAsync(HttpResponseMessage response)
+    {
+        var body = JsonDocument.Parse(await response.Content.ReadAsStringAsync());
+        return body.RootElement
+            .GetProperty("items")
+            .EnumerateArray()
+            .Select(item => item.Clone())
+            .ToArray();
+    }
+}