diff --git a/Backend/MotoresArgentinosV2.API/Controllers/AuthController.cs b/Backend/MotoresArgentinosV2.API/Controllers/AuthController.cs
index f4b34f7..40bc104 100644
--- a/Backend/MotoresArgentinosV2.API/Controllers/AuthController.cs
+++ b/Backend/MotoresArgentinosV2.API/Controllers/AuthController.cs
@@ -11,7 +11,7 @@ namespace MotoresArgentinosV2.API.Controllers;
 
 [ApiController]
 [Route("api/[controller]")]
-// CORRECCIÓN: Se quitó [EnableRateLimiting("AuthPolicy")] de aquí para no bloquear /me ni /logout
+[EnableRateLimiting("AuthPolicy")]
 public class AuthController : ControllerBase
 {
     private readonly IIdentityService _identityService;
@@ -33,7 +33,7 @@ public class AuthController : ControllerBase
         var cookieOptions = new CookieOptions
         {
             HttpOnly = true, // Seguridad: JS no puede leer esto
-            Expires = DateTime.UtcNow.AddDays(7),
+            Expires = DateTime.UtcNow.AddMinutes(15),
             Secure = true, // Solo HTTPS (localhost con https cuenta)
             SameSite = SameSiteMode.Strict,
             IsEssential = true
diff --git a/Backend/MotoresArgentinosV2.API/Controllers/SeedController.cs b/Backend/MotoresArgentinosV2.API/Controllers/SeedController.cs
deleted file mode 100644
index b8ee48b..0000000
--- a/Backend/MotoresArgentinosV2.API/Controllers/SeedController.cs
+++ /dev/null
@@ -1,180 +0,0 @@
-using Microsoft.AspNetCore.Mvc;
-using Microsoft.EntityFrameworkCore;
-using MotoresArgentinosV2.Infrastructure.Data;
-using MotoresArgentinosV2.Core.Entities;
-using MotoresArgentinosV2.Core.Interfaces;
-
-namespace MotoresArgentinosV2.API.Controllers;
-
-[ApiController]
-[Route("api/[controller]")]
-public class SeedController : ControllerBase
-{
-    private readonly MotoresV2DbContext _context;
-    private readonly IPasswordService _passwordService;
-
-    public SeedController(MotoresV2DbContext context, IPasswordService passwordService)
-    {
-        _context = context;
-        _passwordService = passwordService;
-    }
-
-    [HttpPost("database")]
-    public async Task<IActionResult> SeedDatabase()
-    {
-        // 1. Asegurar Marcas y Modelos
-        if (!await _context.Brands.AnyAsync())
-        {
-            var toyota = new Brand { VehicleTypeID = 1, Name = "Toyota" };
-            var ford = new Brand { VehicleTypeID = 1, Name = "Ford" };
-            var vw = new Brand { VehicleTypeID = 1, Name = "Volkswagen" };
-            var honda = new Brand { VehicleTypeID = 2, Name = "Honda" };
-            var yamaha = new Brand { VehicleTypeID = 2, Name = "Yamaha" };
-
-            _context.Brands.AddRange(toyota, ford, vw, honda, yamaha);
-            await _context.SaveChangesAsync();
-
-            _context.Models.AddRange(
-                new Model { BrandID = toyota.BrandID, Name = "Corolla" },
-                new Model { BrandID = toyota.BrandID, Name = "Hilux" },
-                new Model { BrandID = ford.BrandID, Name = "Ranger" },
-                new Model { BrandID = vw.BrandID, Name = "Amarok" },
-                new Model { BrandID = honda.BrandID, Name = "Wave 110" },
-                new Model { BrandID = yamaha.BrandID, Name = "FZ FI" }
-            );
-            await _context.SaveChangesAsync();
-        }
-
-        // 2. Crear Usuarios de Prueba
-        var testUser = await _context.Users.FirstOrDefaultAsync(u => u.UserName == "testuser");
-        if (testUser == null)
-        {
-            testUser = new User 
-            { 
-                UserName = "testuser", 
-                Email = "test@motores.com.ar", 
-                PasswordHash = _passwordService.HashPassword("test123"), 
-                FirstName = "Usuario",
-                LastName = "Prueba",
-                MigrationStatus = 1,
-                UserType = 1
-            };
-            _context.Users.Add(testUser);
-        }
-
-        var adminUser = await _context.Users.FirstOrDefaultAsync(u => u.UserName == "admin");
-        if (adminUser == null)
-        {
-            adminUser = new User
-            {
-                UserName = "admin",
-                Email = "admin@motoresargentinos.com.ar",
-                PasswordHash = _passwordService.HashPassword("admin123"),
-                FirstName = "Admin",
-                LastName = "Motores",
-                MigrationStatus = 1,
-                UserType = 3 // ADMIN
-            };
-            _context.Users.Add(adminUser);
-        }
-
-        await _context.SaveChangesAsync();
-
-        // 3. Crear Avisos de Prueba
-        if (!await _context.Ads.AnyAsync())
-        {
-            var brands = await _context.Brands.ToListAsync();
-            var models = await _context.Models.ToListAsync();
-
-            var ad1 = new Ad
-            {
-                UserID = testUser.UserID,
-                VehicleTypeID = 1,
-                BrandID = brands.First(b => b.Name == "Toyota").BrandID,
-                ModelID = models.First(m => m.Name == "Corolla").ModelID,
-                VersionName = "Toyota Corolla 1.8 XLI",
-                Year = 2022,
-                KM = 15000,
-                Price = 25000,
-                Currency = "USD",
-                Description = "Excelente estado, único dueño. Service al día.",
-                StatusID = 4, // Activo
-                IsFeatured = true,
-                CreatedAt = DateTime.UtcNow,
-                PublishedAt = DateTime.UtcNow
-            };
-
-            var ad2 = new Ad
-            {
-                UserID = testUser.UserID,
-                VehicleTypeID = 2,
-                BrandID = brands.First(b => b.Name == "Honda").BrandID,
-                ModelID = models.First(m => m.Name == "Wave 110").ModelID,
-                VersionName = "Honda Wave 110 S",
-                Year = 2023,
-                KM = 2500,
-                Price = 1800,
-                Currency = "USD",
-                Description = "Impecable, como nueva. Muy económica.",
-                StatusID = 4, // Activo
-                CreatedAt = DateTime.UtcNow,
-                PublishedAt = DateTime.UtcNow
-            };
-
-            var ad3 = new Ad
-            {
-                UserID = testUser.UserID,
-                VehicleTypeID = 1,
-                BrandID = brands.First(b => b.Name == "Ford").BrandID,
-                ModelID = models.First(m => m.Name == "Ranger").ModelID,
-                VersionName = "Ford Ranger Limited 4x4",
-                Year = 2021,
-                KM = 35000,
-                Price = 42000,
-                Currency = "USD",
-                Description = "Camioneta impecable, lista para transferir.",
-                StatusID = 3, // Moderacion Pendiente
-                CreatedAt = DateTime.UtcNow
-            };
-
-            _context.Ads.AddRange(ad1, ad2, ad3);
-            await _context.SaveChangesAsync();
-
-            // Agregar fotos
-            _context.AdPhotos.AddRange(
-                new AdPhoto { AdID = ad1.AdID, FilePath = "https://images.unsplash.com/photo-1621007947382-bb3c3994e3fb?auto=format&fit=crop&q=80&w=1200", IsCover = true },
-                new AdPhoto { AdID = ad1.AdID, FilePath = "https://images.unsplash.com/photo-1590362891991-f776e933a68e?auto=format&fit=crop&q=80&w=1200" },
-                new AdPhoto { AdID = ad1.AdID, FilePath = "https://images.unsplash.com/photo-1549317661-bd32c8ce0db2?auto=format&fit=crop&q=80&w=1200" },
-                new AdPhoto { AdID = ad2.AdID, FilePath = "https://images.unsplash.com/photo-1558981403-c5f91cbba527?auto=format&fit=crop&q=80&w=800", IsCover = true },
-                new AdPhoto { AdID = ad3.AdID, FilePath = "https://images.unsplash.com/photo-1533473359331-0135ef1b58bf?auto=format&fit=crop&q=80&w=1200", IsCover = true }
-            );
-
-            // Agregar Características Técnicas
-            _context.AdFeatures.AddRange(
-                new AdFeature { AdID = ad1.AdID, FeatureKey = "Combustible", FeatureValue = "Nafta" },
-                new AdFeature { AdID = ad1.AdID, FeatureKey = "Transmision", FeatureValue = "Automática" },
-                new AdFeature { AdID = ad1.AdID, FeatureKey = "Color", FeatureValue = "Blanco" },
-                new AdFeature { AdID = ad2.AdID, FeatureKey = "Combustible", FeatureValue = "Nafta" },
-                new AdFeature { AdID = ad2.AdID, FeatureKey = "Color", FeatureValue = "Rojo" }
-            );
-
-            await _context.SaveChangesAsync();
-        }
-
-        return Ok("Database seeded successfully with Features and Multiple Photos");
-    }
-
-    [HttpPost("reset")]
-    public async Task<IActionResult> ResetDatabase()
-    {
-        _context.ChangeTracker.Clear();
-        await _context.Database.ExecuteSqlRawAsync("DELETE FROM Transactions");
-        await _context.Database.ExecuteSqlRawAsync("DELETE FROM AdPhotos");
-        await _context.Database.ExecuteSqlRawAsync("DELETE FROM AdFeatures");
-        await _context.Database.ExecuteSqlRawAsync("DELETE FROM Ads");
-        await _context.Database.ExecuteSqlRawAsync("DELETE FROM Models");
-        await _context.Database.ExecuteSqlRawAsync("DELETE FROM Brands");
-        
-        return await SeedDatabase();
-    }
-}
diff --git a/Backend/MotoresArgentinosV2.API/Middleware/ExceptionHandlingMiddleware.cs b/Backend/MotoresArgentinosV2.API/Middleware/ExceptionHandlingMiddleware.cs
new file mode 100644
index 0000000..e45e545
--- /dev/null
+++ b/Backend/MotoresArgentinosV2.API/Middleware/ExceptionHandlingMiddleware.cs
@@ -0,0 +1,52 @@
+using Microsoft.AspNetCore.Http;
+using Microsoft.Extensions.Logging;
+using System.Net;
+using System.Text.Json;
+
+namespace MotoresArgentinosV2.API.Middleware;
+
+public class ExceptionHandlingMiddleware
+{
+    private readonly RequestDelegate _next;
+    private readonly ILogger<ExceptionHandlingMiddleware> _logger;
+    private readonly IHostEnvironment _env;
+
+    public ExceptionHandlingMiddleware(RequestDelegate next, ILogger<ExceptionHandlingMiddleware> logger, IHostEnvironment env)
+    {
+        _next = next;
+        _logger = logger;
+        _env = env;
+    }
+
+    public async Task InvokeAsync(HttpContext context)
+    {
+        try
+        {
+            await _next(context);
+        }
+        catch (Exception ex)
+        {
+            await HandleExceptionAsync(context, ex);
+        }
+    }
+
+    private async Task HandleExceptionAsync(HttpContext context, Exception exception)
+    {
+        // Loguear el error real con stack trace completo
+        _logger.LogError(exception, "Error no controlado procesando la solicitud: {Method} {Path}", context.Request.Method, context.Request.Path);
+
+        context.Response.ContentType = "application/json";
+        context.Response.StatusCode = (int)HttpStatusCode.InternalServerError;
+
+        var response = new
+        {
+            status = context.Response.StatusCode,
+            message = "Ocurrió un error interno en el servidor. Por favor, intente nuevamente más tarde.",
+            // En desarrollo mostramos el detalle, en producción ocultamos todo
+            detail = _env.IsDevelopment() ? exception.Message : null
+        };
+
+        var json = JsonSerializer.Serialize(response);
+        await context.Response.WriteAsync(json);
+    }
+}
diff --git a/Backend/MotoresArgentinosV2.API/Program.cs b/Backend/MotoresArgentinosV2.API/Program.cs
index b941546..453ff19 100644
--- a/Backend/MotoresArgentinosV2.API/Program.cs
+++ b/Backend/MotoresArgentinosV2.API/Program.cs
@@ -78,25 +78,28 @@ builder.Services.AddRateLimiter(options =>
 
     options.AddPolicy("AuthPolicy", context =>
     {
-        // Si es localhost, SIN LÍMITES
+        // Si es localhost, SIN LÍMITES (Evita auto-bloqueo en desarrollo)
         var remoteIp = context.Connection.RemoteIpAddress;
-        if (System.Net.IPAddress.IsLoopback(remoteIp!))
+        if (remoteIp != null && System.Net.IPAddress.IsLoopback(remoteIp))
         {
             return RateLimitPartition.GetNoLimiter("loopback_auth");
         }
 
-        return RateLimitPartition.GetFixedWindowLimiter(
-            partitionKey: remoteIp?.ToString() ?? "unknown",
-            factory: _ => new FixedWindowRateLimiterOptions
-            {
-                AutoReplenishment = true,
-                PermitLimit = 5, // 5 intentos por minuto para IPs externas
-                QueueLimit = 0,
-                Window = TimeSpan.FromMinutes(1)
-            });
+        return RateLimitPartition.GetFixedWindowLimiter("auth_limit", _ => new FixedWindowRateLimiterOptions
+        {
+            PermitLimit = 5,
+            Window = TimeSpan.FromMinutes(1),
+            QueueLimit = 0
+        });
     });
 });
 
+// 🛡️ SEGURIDAD: Evitar que el host se caiga si un servicio de fondo falla
+builder.Services.Configure<HostOptions>(options =>
+{
+    options.BackgroundServiceExceptionBehavior = BackgroundServiceExceptionBehavior.Ignore;
+});
+
 // DB CONTEXTS (Legacy unificado en eldia)
 builder.Services.AddDbContext<EldiaDbContext>(options =>
     options.UseSqlServer(builder.Configuration.GetConnectionString("eldia")));
@@ -119,6 +122,7 @@ builder.Services.Configure<MailSettings>(builder.Configuration.GetSection("SmtpS
 builder.Services.AddScoped<IEmailService, SmtpEmailService>();
 builder.Services.AddScoped<IImageStorageService, ImageStorageService>();
 builder.Services.AddHostedService<AdExpirationService>();
+builder.Services.AddHostedService<TokenCleanupService>();
 
 // 🔒 JWT AUTH
 var jwtKey = builder.Configuration["Jwt:Key"] ?? throw new InvalidOperationException("JWT Key Missing");
@@ -158,8 +162,10 @@ builder.Services.AddSwaggerGen();
 
 var app = builder.Build();
 
-// USAR EL MIDDLEWARE AL PRINCIPIO
-// Debe ser lo primero para que el RateLimiter y los Logs vean la IP real
+// Middleware de Manejo Global de Excepciones (Debe ser el primero para atrapar todo)
+app.UseMiddleware<MotoresArgentinosV2.API.Middleware.ExceptionHandlingMiddleware>();
+
+// USAR EL MIDDLEWARE DE HEADERS
 app.UseForwardedHeaders();
 
 // 🔒 HEADERS DE SEGURIDAD MIDDLEWARE
@@ -170,6 +176,9 @@ app.Use(async (context, next) =>
     context.Response.Headers.Append("Referrer-Policy", "strict-origin-when-cross-origin");
     context.Response.Headers.Append("X-XSS-Protection", "1; mode=block");
 
+    // Permissions-Policy: Bloquear funcionalidades sensibles del navegador no usadas
+    context.Response.Headers.Append("Permissions-Policy", "accelerometer=(), camera=(), geolocation=(), gyroscope=(), magnetometer=(), microphone=(), payment=(), usb=()");
+
     // CSP adaptada para permitir pagos en Payway y WebSockets de Vite
     string csp = "default-src 'self'; " +
                  "img-src 'self' data: https: blob:; " +
diff --git a/Backend/MotoresArgentinosV2.Infrastructure/Services/AdExpirationService.cs b/Backend/MotoresArgentinosV2.Infrastructure/Services/AdExpirationService.cs
index 235c714..9aba90b 100644
--- a/Backend/MotoresArgentinosV2.Infrastructure/Services/AdExpirationService.cs
+++ b/Backend/MotoresArgentinosV2.Infrastructure/Services/AdExpirationService.cs
@@ -43,14 +43,19 @@ public class AdExpirationService : BackgroundService
         await ProcessWeeklyStatsAsync();
         await ProcessPaymentRemindersAsync();
         await ProcessUnreadMessagesRemindersAsync();
+
+        // Ejecutar cada 1 hora
+        await Task.Delay(TimeSpan.FromHours(1), stoppingToken);
+      }
+      catch (OperationCanceledException)
+      {
+        break;
       }
       catch (Exception ex)
       {
         _logger.LogError(ex, "Error CRÍTICO en ciclo de mantenimiento.");
+        await Task.Delay(TimeSpan.FromMinutes(5), stoppingToken);
       }
-
-      // Ejecutar cada 1 hora
-      await Task.Delay(TimeSpan.FromHours(1), stoppingToken);
     }
   }
 
diff --git a/Backend/MotoresArgentinosV2.Infrastructure/Services/TokenCleanupService.cs b/Backend/MotoresArgentinosV2.Infrastructure/Services/TokenCleanupService.cs
new file mode 100644
index 0000000..a42d675
--- /dev/null
+++ b/Backend/MotoresArgentinosV2.Infrastructure/Services/TokenCleanupService.cs
@@ -0,0 +1,72 @@
+using Microsoft.Extensions.Hosting;
+using Microsoft.Extensions.Logging;
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.EntityFrameworkCore;
+using MotoresArgentinosV2.Infrastructure.Data;
+
+namespace MotoresArgentinosV2.Infrastructure.Services;
+
+public class TokenCleanupService : BackgroundService
+{
+    private readonly IServiceProvider _serviceProvider;
+    private readonly ILogger<TokenCleanupService> _logger;
+    private readonly TimeSpan _cleanupInterval = TimeSpan.FromHours(24); // Ejecutar cada 24hs
+
+    public TokenCleanupService(IServiceProvider serviceProvider, ILogger<TokenCleanupService> logger)
+    {
+        _serviceProvider = serviceProvider;
+        _logger = logger;
+    }
+
+    protected override async Task ExecuteAsync(CancellationToken stoppingToken)
+    {
+        _logger.LogInformation("Servicio de Limpieza de Tokens iniciado.");
+
+        while (!stoppingToken.IsCancellationRequested)
+        {
+            try
+            {
+                await CleanExpiredTokensAsync(stoppingToken);
+                // Esperar hasta la próxima ejecución
+                await Task.Delay(_cleanupInterval, stoppingToken);
+            }
+            catch (OperationCanceledException)
+            {
+                // El servicio se está deteniendo, es normal
+                break;
+            }
+            catch (Exception ex)
+            {
+                _logger.LogError(ex, "Error durante la limpieza de tokens.");
+                // Si hay un error, esperamos un poco antes de reintentar (evitar bucle infinito de errores)
+                await Task.Delay(TimeSpan.FromMinutes(5), stoppingToken);
+            }
+        }
+    }
+
+    private async Task CleanExpiredTokensAsync(CancellationToken stoppingToken)
+    {
+        using (var scope = _serviceProvider.CreateScope())
+        {
+            var context = scope.ServiceProvider.GetRequiredService<MotoresV2DbContext>();
+            
+            // Definir criterios de limpieza
+            var cutoffDate = DateTime.UtcNow; // Tokens ya expirados
+            var revokedCutoff = DateTime.UtcNow.AddDays(-30); // Tokens revocados hace más de 30 días (auditoría)
+
+            _logger.LogInformation("Ejecutando limpieza de RefreshTokens expirados o antiguos...");
+
+            // Opción 1: Borrado con SQL Raw para eficiencia en lotes grandes
+            // Asumimos que la tabla se llama 'RefreshTokens' en la DB
+            var rowsAffected = await context.Database.ExecuteSqlRawAsync(
+                "DELETE FROM [RefreshTokens] WHERE [Expires] < @cutoffDate OR ([Revoked] IS NOT NULL AND [Revoked] < @revokedCutoff)",
+                new[] { 
+                    new Microsoft.Data.SqlClient.SqlParameter("@cutoffDate", cutoffDate),
+                    new Microsoft.Data.SqlClient.SqlParameter("@revokedCutoff", revokedCutoff)
+                },
+                stoppingToken);
+
+            _logger.LogInformation("Limpieza completada. {Count} tokens eliminados.", rowsAffected);
+        }
+    }
+}
diff --git a/Backend/MotoresArgentinosV2.Infrastructure/Services/TokenService.cs b/Backend/MotoresArgentinosV2.Infrastructure/Services/TokenService.cs
index 374d65c..0d46e53 100644
--- a/Backend/MotoresArgentinosV2.Infrastructure/Services/TokenService.cs
+++ b/Backend/MotoresArgentinosV2.Infrastructure/Services/TokenService.cs
@@ -33,7 +33,7 @@ public class TokenService : ITokenService
                 new Claim(ClaimTypes.Email, user.Email),
                 new Claim(ClaimTypes.Role, user.UserType == 3 ? "Admin" : "User")
             }),
-            Expires = DateTime.UtcNow.AddHours(8),
+            Expires = DateTime.UtcNow.AddMinutes(15),
             SigningCredentials = new SigningCredentials(new SymmetricSecurityKey(key), SecurityAlgorithms.HmacSha256Signature),
             Issuer = _config["Jwt:Issuer"],
             Audience = _config["Jwt:Audience"]
diff --git a/Frontend/nginx.conf b/Frontend/nginx.conf
index 4744cab..6a90ae7 100644
--- a/Frontend/nginx.conf
+++ b/Frontend/nginx.conf
@@ -1,6 +1,9 @@
 server {
     listen 80;
     server_name localhost;
+    
+    # Seguridad: Limitar tamaño de subida para prevenir DoS
+    client_max_body_size 20M;
 
     location / {
         root /usr/share/nginx/html;
diff --git a/Frontend/src/index.css b/Frontend/src/index.css
index bb7a6b9..2d91f3c 100644
--- a/Frontend/src/index.css
+++ b/Frontend/src/index.css
@@ -8,6 +8,8 @@
 
   --animate-fade-in-up: fade-in-up 0.5s ease-out;
   --animate-glow: glow 2s infinite alternate;
+  --animate-fade-in: fade-in 0.3s ease-out forwards;
+  --animate-scale-up: scale-up 0.3s cubic-bezier(0.34, 1.56, 0.64, 1) forwards;
 
   @keyframes fade-in-up {
     from {
@@ -52,16 +54,22 @@
       transform: scale(1);
     }
   }
-
-  .animate-fade-in {
-    animation: fade-in 0.3s ease-out forwards;
-  }
-
-  .animate-scale-up {
-    animation: scale-up 0.3s cubic-bezier(0.34, 1.56, 0.64, 1) forwards;
-  }
 }
 
+/* Clases de utilidad personalizadas (fuera de @theme) */
+.animate-fade-in {
+  animation: var(--animate-fade-in);
+}
+
+.animate-scale-up {
+  animation: var(--animate-scale-up);
+}
+
+.animate-fade-in-up {
+  animation: var(--animate-fade-in-up);
+}
+
+
 :root {
   background-color: var(--color-dark-bg);
   color: white;
diff --git a/Frontend/vite.config.ts b/Frontend/vite.config.ts
index 3d15f68..6ce20f0 100644
--- a/Frontend/vite.config.ts
+++ b/Frontend/vite.config.ts
@@ -8,4 +8,7 @@ export default defineConfig({
     react(),
     tailwindcss(),
   ],
+  build: {
+    sourcemap: false, // Seguridad: Ocultar código fuente en producción
+  },
 })