feat(auth): add email verification codes

- Add POST /auth/verification-code endpoint to email a code
- Store codes in Redis and verify them during registration
- Send verification emails asynchronously via Thymeleaf
- Replace email_verified column with code-based verification
- Group dependencies into version catalogue bundles

src/main/java/com/onixbyte/deltaforceguide/DeltaForceGuideApplication.java

@@ -2,12 +2,14 @@ package com.onixbyte.deltaforceguide;
 
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.scheduling.annotation.EnableAsync;
 
 /**
  * Entry point for the Delta Force Guide Server application.
  *
  * @author zihluwang
  */
+@EnableAsync
 @SpringBootApplication
 public class DeltaForceGuideApplication {
 

src/main/java/com/onixbyte/deltaforceguide/client/EmailClient.java

@@ -0,0 +1,105 @@
+package com.onixbyte.deltaforceguide.client;
+
+import jakarta.mail.MessagingException;
+import jakarta.mail.internet.InternetAddress;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.mail.javamail.JavaMailSender;
+import org.springframework.mail.javamail.MimeMessageHelper;
+import org.springframework.scheduling.annotation.Async;
+import org.springframework.stereotype.Component;
+import org.thymeleaf.TemplateEngine;
+import org.thymeleaf.context.Context;
+
+import java.io.UnsupportedEncodingException;
+import java.nio.charset.StandardCharsets;
+import java.util.Map;
+
+@Component
+public class EmailClient {
+
+    private static final Logger log = LoggerFactory.getLogger(EmailClient.class);
+
+    private final JavaMailSender mailSender;
+
+    private final TemplateEngine emailTemplateEngine;
+
+    @Value("${spring.mail.username}")
+    private String fromAddress;
+
+    @Autowired
+    public EmailClient(
+            JavaMailSender mailSender,
+            TemplateEngine emailTemplateEngine
+    ) {
+        this.mailSender = mailSender;
+        this.emailTemplateEngine = emailTemplateEngine;
+    }
+
+    /**
+     * Send a template-based HTML email asynchronously.
+     *
+     * @param toRecipient  recipient email address
+     * @param subject      subject line
+     * @param templateName template name (without .html extension, under mail-templates/)
+     * @param variables    context variables required by the template
+     */
+    @Async
+    public void sendTemplateMail(String toRecipient, String subject, String templateName, Map<String, Object> variables) {
+        try {
+            // Render HTML content using the dedicated email template engine
+            var context = new Context();
+            if (variables != null && !variables.isEmpty()) {
+                context.setVariables(variables);
+            }
+            var htmlBody = emailTemplateEngine.process(templateName, context);
+
+            log.debug("htmlBody={}", htmlBody);
+
+            // Build the MIME message
+            var message = mailSender.createMimeMessage();
+            var helper = new MimeMessageHelper(
+                    message,
+                    MimeMessageHelper.MULTIPART_MODE_MIXED_RELATED,
+                    StandardCharsets.UTF_8.name()
+            );
+
+            helper.setFrom(new InternetAddress(fromAddress, "阿萨拉向导", StandardCharsets.UTF_8.name()));
+            helper.setTo(toRecipient);
+            helper.setSubject(subject);
+            helper.setText(htmlBody, true);
+
+            // Dispatch the message
+            mailSender.send(message);
+            log.info("Successfully dispatched email to: [{}] with subject: [{}]", toRecipient, subject);
+
+        } catch (MessagingException | UnsupportedEncodingException ex) {
+            log.error("Failed to construct or send email to: [{}], subject: [{}]", toRecipient, subject, ex);
+            // Handle or rethrow custom business exception if required
+        } catch (Exception ex) {
+            log.error("Unexpected error occurred while processing email for: [{}]", toRecipient, ex);
+        }
+    }
+
+    /**
+     * Convenience method specifically for sending registration/login verification codes.
+     *
+     * @param toRecipient   target recipient email
+     * @param username      display username
+     * @param code          verification code string
+     * @param expireMinutes expiration time in minutes
+     */
+    @Async
+    public void sendVerificationCode(String toRecipient, String username, String code, int expireMinutes) {
+        var subject = "【阿萨拉向导】账号注册验证码";
+        var variables = Map.<String, Object>of(
+                "username", username,
+                "code", code,
+                "expireMinutes", expireMinutes
+        );
+
+        sendTemplateMail(toRecipient, subject, "verification-code", variables);
+    }
+}

src/main/java/com/onixbyte/deltaforceguide/config/EmailTemplateConfig.java

@@ -0,0 +1,37 @@
+package com.onixbyte.deltaforceguide.config;
+
+import com.onixbyte.captcha.text.TextProducer;
+import com.onixbyte.captcha.text.impl.DefaultTextProducer;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.thymeleaf.TemplateEngine;
+import org.thymeleaf.spring6.SpringTemplateEngine;
+import org.thymeleaf.templatemode.TemplateMode;
+import org.thymeleaf.templateresolver.ClassLoaderTemplateResolver;
+import org.thymeleaf.templateresolver.ITemplateResolver;
+
+import java.nio.charset.StandardCharsets;
+
+@Configuration
+public class EmailTemplateConfig {
+
+    @Bean
+    public TemplateEngine emailTemplateEngine() {
+        var resolver = new ClassLoaderTemplateResolver();
+        // Template files are located under src/main/resources/mail-templates/
+        resolver.setPrefix("mail-templates/");
+        resolver.setSuffix(".html");
+        resolver.setTemplateMode(TemplateMode.HTML);
+        resolver.setCharacterEncoding(StandardCharsets.UTF_8.name());
+        resolver.setCacheable(true); // Enable caching for the production environment
+
+        var templateEngine = new SpringTemplateEngine();
+        templateEngine.addTemplateResolver(resolver);
+        return templateEngine;
+    }
+
+    @Bean
+    public TextProducer textProducer() {
+        return DefaultTextProducer.builder().build();
+    }
+}

src/main/java/com/onixbyte/deltaforceguide/controller/AuthController.java

@@ -1,8 +1,6 @@
 package com.onixbyte.deltaforceguide.controller;
 
-import com.onixbyte.deltaforceguide.domain.dto.LoginRequest;
-import com.onixbyte.deltaforceguide.domain.dto.RegisterRequest;
-import com.onixbyte.deltaforceguide.domain.dto.UserResponse;
+import com.onixbyte.deltaforceguide.domain.dto.*;
 import com.onixbyte.deltaforceguide.security.annotation.RequiresAuth;
 import com.onixbyte.deltaforceguide.service.AuthService;
 import io.swagger.v3.oas.annotations.Operation;
@@ -48,6 +46,13 @@ public class AuthController {
                 .build();
     }
 
+    @Operation(description = "发送邮件验证码")
+    @PostMapping("/verification-code")
+    public SendVerificationCodeResponse sendVerificationCode(@Validated @RequestBody SendVerificationCodeRequest request) {
+        var verificationCodeId = authService.sendVerificationCode(request);
+        return new SendVerificationCodeResponse(verificationCodeId);
+    }
+
     @Operation(description = "用户注册")
     @PostMapping("/register")
     public ResponseEntity<UserResponse> register(@Validated @RequestBody RegisterRequest request) {

src/main/java/com/onixbyte/deltaforceguide/domain/dto/RegisterRequest.java

@@ -24,6 +24,8 @@ public record RegisterRequest(
         String avatarUrl,
         @NotBlank(message = "密码不能为空")
         @Schema(description = "密码", requiredMode = Schema.RequiredMode.REQUIRED)
-        String password
+        String password,
+        @NotBlank(message = "验证码 ID 不能为空") String verificationCodeId,
+        @NotBlank(message = "验证码不能为空") String verificationCode
 ) {
 }

src/main/java/com/onixbyte/deltaforceguide/domain/dto/SendVerificationCodeRequest.java

@@ -0,0 +1,9 @@
+package com.onixbyte.deltaforceguide.domain.dto;
+
+import jakarta.validation.constraints.NotBlank;
+
+public record SendVerificationCodeRequest(
+        @NotBlank(message = "用户名不能为空") String username,
+        @NotBlank(message = "电子邮箱地址不能为空") String email
+) {
+}

src/main/java/com/onixbyte/deltaforceguide/domain/dto/SendVerificationCodeResponse.java

@@ -0,0 +1,6 @@
+package com.onixbyte.deltaforceguide.domain.dto;
+
+public record SendVerificationCodeResponse(
+        String verificationCodeId
+) {
+}

src/main/java/com/onixbyte/deltaforceguide/domain/dto/UpdateProfileRequest.java

@@ -10,9 +10,5 @@ import jakarta.validation.constraints.Size;
  */
 public record UpdateProfileRequest(
         @Size(min = 1, max = 64, message = "昵称长度必须在1-64个字符之间")
-        String nickname,
-
-        @Email(message = "请输入正确的电子邮箱地址")
-        @Size(max = 255, message = "电子邮箱长度不能超过255个字符")
-        String email
+        String nickname
 ) {}

src/main/java/com/onixbyte/deltaforceguide/domain/dto/UserProfileResponse.java

@@ -16,7 +16,6 @@ public record UserProfileResponse(
         String nickname,
         String email,
         String avatarUrl,
-        Boolean emailVerified,
         Boolean enabled,
         LocalDateTime createdAt,
         List<String> roles
@@ -37,7 +36,6 @@ public record UserProfileResponse(
                         ? user.getUsername() : user.getNickname(),
                 user.getEmail(),
                 user.getAvatarUrl(),
-                user.getEmailVerified(),
                 user.getEnabled(),
                 user.getCreatedAt(),
                 roles

src/main/java/com/onixbyte/deltaforceguide/domain/entity/User.java

@@ -39,9 +39,6 @@ public class User {
     @Column(name = "avatar_url")
     private String avatarUrl;
 
-    @Column(name = "email_verified", nullable = false)
-    private Boolean emailVerified = false;
-
     @Column(name = "enabled", nullable = false)
     private Boolean enabled = true;
 
@@ -94,14 +91,6 @@ public class User {
         this.avatarUrl = avatarUrl;
     }
 
-    public Boolean getEmailVerified() {
-        return emailVerified;
-    }
-
-    public void setEmailVerified(Boolean emailVerified) {
-        this.emailVerified = emailVerified;
-    }
-
     public Boolean getEnabled() {
         return enabled;
     }
@@ -160,7 +149,6 @@ public class User {
         private String email;
         private String nickname;
         private String avatarUrl;
-        private Boolean emailVerified;
         private Boolean enabled;
         private LocalDateTime createdAt;
         private LocalDateTime updatedAt;
@@ -191,11 +179,6 @@ public class User {
             return this;
         }
 
-        public Builder emailVerified(Boolean emailVerified) {
-            this.emailVerified = emailVerified;
-            return this;
-        }
-
         public Builder enabled(Boolean enabled) {
             this.enabled = enabled;
             return this;
@@ -224,7 +207,6 @@ public class User {
             user.nickname = this.nickname == null || this.nickname.isBlank()
                     ? this.username : this.nickname;
             user.avatarUrl = this.avatarUrl;
-            user.emailVerified = this.emailVerified != null && this.emailVerified;
             user.enabled = this.enabled == null || this.enabled;
             user.createdAt = this.createdAt;
             user.updatedAt = this.updatedAt;

src/main/java/com/onixbyte/deltaforceguide/exeption/ConflictException.java

@@ -0,0 +1,11 @@
+package com.onixbyte.deltaforceguide.exeption;
+
+import org.springframework.http.HttpStatus;
+import org.springframework.web.server.ResponseStatusException;
+
+public class ConflictException extends ResponseStatusException {
+
+    public ConflictException(String reason) {
+        super(HttpStatus.CONFLICT, reason);
+    }
+}

src/main/java/com/onixbyte/deltaforceguide/repository/BaseRepository.java

@@ -1,7 +0,0 @@
-package com.onixbyte.deltaforceguide.repository;
-
-import org.springframework.data.jpa.repository.JpaRepository;
-import org.springframework.data.jpa.repository.JpaSpecificationExecutor;
-
-public interface BaseRepository<T, K> extends JpaRepository<T, K>, JpaSpecificationExecutor<T> {
-}

src/main/java/com/onixbyte/deltaforceguide/repository/FirearmRepository.java

@@ -5,6 +5,7 @@ import com.onixbyte.deltaforceguide.enumeration.FirearmType;
 import org.springframework.data.domain.Page;
 import org.springframework.data.domain.Pageable;
 import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.data.jpa.repository.JpaSpecificationExecutor;
 import org.springframework.stereotype.Repository;
 
 import java.util.List;
@@ -15,7 +16,7 @@ import java.util.List;
  * @author zihluwang
  */
 @Repository
-public interface FirearmRepository extends BaseRepository<Firearm, Long> {
+public interface FirearmRepository extends JpaRepository<Firearm, Long>, JpaSpecificationExecutor<Firearm> {
 
 	Page<Firearm> findAllByType(FirearmType type, Pageable pageable);
 

src/main/java/com/onixbyte/deltaforceguide/repository/ModificationRepository.java

@@ -6,6 +6,7 @@ import org.springframework.data.domain.Page;
 import org.springframework.data.domain.Pageable;
 import org.springframework.data.jpa.repository.EntityGraph;
 import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.data.jpa.repository.JpaSpecificationExecutor;
 import org.springframework.data.jpa.repository.Query;
 import org.springframework.data.repository.query.Param;
 import org.springframework.stereotype.Repository;
@@ -20,7 +21,7 @@ import java.util.Optional;
  * @author zihluwang
  */
 @Repository
-public interface ModificationRepository extends BaseRepository<Modification, Long> {
+public interface ModificationRepository extends JpaRepository<Modification, Long>, JpaSpecificationExecutor<Modification> {
 
     @EntityGraph(attributePaths = {"firearm"})
     Page<Modification> findAllBy(Pageable pageable);

src/main/java/com/onixbyte/deltaforceguide/repository/UserRepository.java

@@ -4,6 +4,7 @@ import com.onixbyte.deltaforceguide.domain.entity.User;
 import org.jspecify.annotations.NonNull;
 import org.springframework.data.jpa.repository.EntityGraph;
 import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.data.jpa.repository.JpaSpecificationExecutor;
 import org.springframework.data.jpa.repository.Query;
 import org.springframework.data.repository.query.Param;
 import org.springframework.stereotype.Repository;
@@ -16,7 +17,7 @@ import java.util.Optional;
  * @author zihluwang
  */
 @Repository
-public interface UserRepository extends BaseRepository<User, Long> {
+public interface UserRepository extends JpaRepository<User, Long>, JpaSpecificationExecutor<User> {
 
     @Override
     @EntityGraph(attributePaths = {"credentials"})

src/main/java/com/onixbyte/deltaforceguide/repository/UserRoleRepository.java

@@ -2,10 +2,7 @@ package com.onixbyte.deltaforceguide.repository;
 
 import com.onixbyte.deltaforceguide.domain.entity.UserRole;
 import com.onixbyte.deltaforceguide.domain.entity.UserRoleId;
-import org.springframework.data.jpa.repository.EntityGraph;
-import org.springframework.data.jpa.repository.JpaRepository;
-import org.springframework.data.jpa.repository.Modifying;
-import org.springframework.data.jpa.repository.Query;
+import org.springframework.data.jpa.repository.*;
 import org.springframework.data.repository.query.Param;
 import org.springframework.stereotype.Repository;
 
@@ -17,7 +14,7 @@ import java.util.List;
  * @author zihluwang
  */
 @Repository
-public interface UserRoleRepository extends BaseRepository<UserRole, UserRoleId> {
+public interface UserRoleRepository extends JpaRepository<UserRole, UserRoleId>, JpaSpecificationExecutor<UserRole> {
 
     /**
      * Find all roles assigned to a given user.

src/main/java/com/onixbyte/deltaforceguide/service/AuthService.java

@@ -1,12 +1,16 @@
 package com.onixbyte.deltaforceguide.service;
 
+import com.onixbyte.captcha.text.TextProducer;
+import com.onixbyte.deltaforceguide.client.EmailClient;
 import com.onixbyte.deltaforceguide.client.TokenClient;
 import com.onixbyte.deltaforceguide.domain.dto.LoginRequest;
 import com.onixbyte.deltaforceguide.domain.dto.RegisterRequest;
+import com.onixbyte.deltaforceguide.domain.dto.SendVerificationCodeRequest;
 import com.onixbyte.deltaforceguide.domain.dto.UserResponse;
 import com.onixbyte.deltaforceguide.domain.entity.User;
 import com.onixbyte.deltaforceguide.domain.entity.UserCredential;
 import com.onixbyte.deltaforceguide.exeption.BadRequestException;
+import com.onixbyte.deltaforceguide.exeption.ConflictException;
 import com.onixbyte.deltaforceguide.exeption.InternalServerErrorException;
 import com.onixbyte.deltaforceguide.manager.CookieManager;
 import com.onixbyte.deltaforceguide.manager.UserManager;
@@ -17,6 +21,8 @@ import com.onixbyte.deltaforceguide.shared.Role;
 import org.jspecify.annotations.NonNull;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
+import org.springframework.cache.CacheManager;
+import org.springframework.data.redis.core.RedisTemplate;
 import org.springframework.http.HttpCookie;
 import org.springframework.http.HttpHeaders;
 import org.springframework.http.ResponseEntity;
@@ -26,6 +32,7 @@ import org.springframework.stereotype.Service;
 
 import java.time.Duration;
 import java.time.LocalDateTime;
+import java.util.UUID;
 
 /**
  * Service handling user authentication, login, and session management.
@@ -41,19 +48,31 @@ public class AuthService {
     private final CookieManager cookieManager;
     private final UserManager userManager;
     private final PasswordEncoder passwordEncoder;
+    private final TextProducer textProducer;
+    private final CacheManager cacheManager;
+    private final RedisTemplate<String, Object> redisTemplate;
+    private final EmailClient emailClient;
 
     public AuthService(
             AuthenticationManager authenticationManager,
             TokenClient tokenClient,
             CookieManager cookieManager,
             UserManager userManager,
-            PasswordEncoder passwordEncoder
+            PasswordEncoder passwordEncoder,
+            TextProducer textProducer,
+            CacheManager cacheManager,
+            RedisTemplate<String, Object> redisTemplate,
+            EmailClient emailClient
     ) {
         this.authenticationManager = authenticationManager;
         this.tokenClient = tokenClient;
         this.cookieManager = cookieManager;
         this.userManager = userManager;
         this.passwordEncoder = passwordEncoder;
+        this.textProducer = textProducer;
+        this.cacheManager = cacheManager;
+        this.redisTemplate = redisTemplate;
+        this.emailClient = emailClient;
     }
 
     /**
@@ -96,6 +115,19 @@ public class AuthService {
             throw new BadRequestException("该邮箱已被注册。");
         }
 
+        var code = request.verificationCode();
+        var verificationCodeId = request.verificationCodeId();
+
+        var storedCode = redisTemplate.opsForValue().get("verification-code:" + verificationCodeId);
+        if (!(storedCode instanceof String strStoredCode)) {
+            log.error("storedCode not a String, storedCode={}", storedCode);
+            throw new InternalServerErrorException("系统内部错误，请重试");
+        }
+
+        if (!code.equalsIgnoreCase(strStoredCode)) {
+            throw new BadRequestException("邮箱验证码不正确，请重试。");
+        }
+
         var now = LocalDateTime.now();
         var user = User.builder()
                 .username(username)
@@ -129,4 +161,39 @@ public class AuthService {
     public HttpCookie logout() {
         return cookieManager.buildCookie(CookieName.ACCESS_TOKEN, "", Duration.ZERO);
     }
+
+    /**
+     * Generates and dispatches a verification code to the given email address.
+     * <p>
+     * The code is cached under the returned UUID for 10 minutes and emailed
+     * asynchronously to the recipient. The UUID must be supplied back to the
+     * server when verifying the code.
+     *
+     * @param request the verification code request containing the target username and email
+     * @return the UUID identifying the verification record, to be used when verifying the code
+     * @throws ConflictException if the username or email is already registered
+     */
+    public String sendVerificationCode(SendVerificationCodeRequest request) {
+        // Check username.
+        if (userManager.existsByUsername(request.username())) {
+            throw new ConflictException("用户名【" + request.username() + "】已被使用。");
+        }
+
+        // Check email address.
+        if (userManager.existsByEmail(request.email())) {
+            throw new ConflictException("邮箱地址【" + request.email() + "】已被使用。");
+        }
+
+        // Generate UUID and verification code.
+        var uuid = UUID.randomUUID().toString().replace("-", "");
+        var code = textProducer.getText();
+
+        // Save verification code to cache.
+        redisTemplate.opsForValue().set("verification-code:" + uuid, code, Duration.ofMinutes(10L));
+
+        // Send email.
+        emailClient.sendVerificationCode(request.email(), request.username(), code, 10);
+
+        return uuid;
+    }
 }

src/main/java/com/onixbyte/deltaforceguide/service/UserService.java

@@ -196,10 +196,7 @@ public class UserService {
         if (StringUtils.hasText(request.nickname())) {
             user.setNickname(request.nickname());
         }
-        if (StringUtils.hasText(request.email()) && !Objects.equals(user.getEmail(), request.email())) {
-            user.setEmail(request.email());
-            user.setEmailVerified(false);
-        }
+
         userManager.save(user);
         return getProfile(user);
     }

src/main/resources/application.yaml

@@ -30,6 +30,8 @@ spring:
   flyway:
     enabled: true
     baseline-on-migrate: true
+  thymeleaf:
+    enabled: false
 
 mybatis:
   configuration:
@@ -40,6 +42,8 @@ mybatis:
   mapper-locations: classpath:/mapper/*.xml
 
 logging:
+  pattern:
+    dateformat: dd MMM yyyy HH:mm:ss
   level:
     org.hibernate:
       orm.connections.pooling: off

src/main/resources/db/migration/V6__user_profile.sql

@@ -1,7 +1,6 @@
 ALTER TABLE app_user
     ADD COLUMN nickname       VARCHAR(64),
     ADD COLUMN avatar_url     VARCHAR(512),
-    ADD COLUMN email_verified BOOLEAN   NOT NULL DEFAULT FALSE,
     ADD COLUMN enabled        BOOLEAN   NOT NULL DEFAULT TRUE,
     ADD COLUMN created_at     TIMESTAMPTZ NOT NULL DEFAULT NOW(),
     ADD COLUMN updated_at     TIMESTAMPTZ NOT NULL DEFAULT NOW();

src/main/resources/mail-templates/verification-code.html

@@ -0,0 +1,71 @@
+<!DOCTYPE html>
+<html xmlns:th="http://www.thymeleaf.org" lang="zh-CN">
+<head>
+    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
+    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
+    <title>账号验证</title>
+</head>
+<body style="margin: 0; padding: 0; background-color: #f1f5f9; font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif; -webkit-font-smoothing: antialiased; -moz-osx-font-smoothing: grayscale;">
+<table role="presentation" border="0" cellpadding="0" cellspacing="0" width="100%" style="background-color: #f1f5f9; padding: 40px 16px;">
+    <tr>
+        <td align="center">
+            <!-- 主容器 -->
+            <table role="presentation" border="0" cellpadding="0" cellspacing="0" width="100%" style="max-width: 520px; background-color: #ffffff; border-radius: 12px; overflow: hidden; box-shadow: 0 4px 12px rgba(15, 23, 42, 0.06); border: 1px solid #e2e8f0;">
+
+                <!-- 顶部标题 -->
+                <tr>
+                    <td align="center" style="padding: 36px 32px 24px; background-color: #ffffff;">
+                        <h1 style="margin: 0; font-size: 22px; font-weight: 700; color: #0f172a; letter-spacing: -0.3px;" th:text="${appName != null ? appName : '账号注册验证'}">账号注册验证</h1>
+                    </td>
+                </tr>
+
+                <!-- 分割线 -->
+                <tr>
+                    <td style="padding: 0 32px;">
+                        <div style="height: 1px; background-color: #f1f5f9; width: 100%;"></div>
+                    </td>
+                </tr>
+
+                <!-- 正文内容 -->
+                <tr>
+                    <td style="padding: 32px 32px 24px;">
+                        <p style="margin: 0 0 16px; font-size: 15px; line-height: 1.6; color: #334155;">
+                            您好 <strong th:text="${username}">用户</strong>，
+                        </p>
+                        <p style="margin: 0 0 24px; font-size: 14px; line-height: 1.6; color: #64748b;">
+                            感谢注册我们的服务。请使用下方的验证码完成账号验证，该验证码在 <strong style="color: #334155;"><span th:text="${expireMinutes}">10</span> 分钟</strong> 内有效：
+                        </p>
+
+                        <!-- 验证码展示区域 -->
+                        <table role="presentation" border="0" cellpadding="0" cellspacing="0" width="100%" style="margin: 8px 0 24px;">
+                            <tr>
+                                <td align="center" style="padding: 20px; background-color: #f8fafc; border: 1px dashed #cbd5e1; border-radius: 8px;">
+                                    <span style="font-family: 'SF Mono', Consolas, 'Liberation Mono', Menlo, monospace; font-size: 32px; font-weight: 700; color: #2563eb; letter-spacing: 8px; margin-left: 8px;" th:text="${code}">123456</span>
+                                </td>
+                            </tr>
+                        </table>
+
+                        <p style="margin: 0 0 12px; font-size: 13px; line-height: 1.6; color: #94a3b8;">
+                            若您未发起此操作或未尝试注册该账号，请直接忽略本邮件。
+                        </p>
+                    </td>
+                </tr>
+
+                <!-- 页脚 -->
+                <tr>
+                    <td align="center" style="padding: 24px 32px; background-color: #f8fafc; border-top: 1px solid #e2e8f0;">
+                        <p style="margin: 0 0 6px; font-size: 12px; line-height: 1.4; color: #94a3b8;">
+                            此邮件为系统自动发送，请勿直接回复。
+                        </p>
+                        <p style="margin: 0; font-size: 12px; color: #cbd5e1;">
+                            &copy; <span th:text="${#calendars.year(#calendars.createNow())}">2026</span> <span>阿萨拉向导</span>. 保留所有权利。
+                        </p>
+                    </td>
+                </tr>
+
+            </table>
+        </td>
+    </tr>
+</table>
+</body>
+</html>