diff --git a/.gitignore b/.gitignore
index 45016ec..c6f27ee 100644
--- a/.gitignore
+++ b/.gitignore
@@ -31,6 +31,8 @@ fuellog-api/coverage.out
 fuellog-api/*.test
 fuellog-api/*.out
 fuellog-api/.air.toml.local
+# Go build temp output (used because Defender blocks the default %LOCALAPPDATA%\Temp)
+.gobuild/
 
 # ===== Database (SQLite) =====
 # Keep the data/ directory, but ignore runtime DB files
diff --git a/fuellog-api/.env.example b/fuellog-api/.env.example
new file mode 100644
index 0000000..95fc8d5
--- /dev/null
+++ b/fuellog-api/.env.example
@@ -0,0 +1,20 @@
+# FuelLog API 配置文件示例
+# 复制到 .env 后按需修改;未设置的字段走默认值
+
+# HTTP 监听地址
+SERVER_ADDR=:8080
+
+# 运行环境:debug | release | test
+GIN_MODE=debug
+
+# SQLite 数据库文件路径(开发期默认 ./data/fuellog.db,容器内挂到 /data/fuellog.db)
+DB_PATH=./data/fuellog.db
+
+# 时区(影响时间格式化;内部统一 UTC 存库)
+TZ=Asia/Shanghai
+
+# 日志级别:debug | info | warn | error
+LOG_LEVEL=info
+
+# 跨域来源(逗号分隔;开发期可用 *)
+CORS_ORIGINS=*
diff --git a/fuellog-api/cmd/server/.gitkeep b/fuellog-api/cmd/server/.gitkeep
new file mode 100644
index 0000000..e69de29
diff --git a/fuellog-api/cmd/server/main.go b/fuellog-api/cmd/server/main.go
new file mode 100644
index 0000000..efd2e80
--- /dev/null
+++ b/fuellog-api/cmd/server/main.go
@@ -0,0 +1,122 @@
+// Command server 是 FuelLog API 入口。
+//
+// 启动流程:
+//  1. 加载 .env
+//  2. 解析配置
+//  3. 初始化数据库(Phase 2 起接 GORM)
+//  4. 装配路由
+//  5. 监听并优雅退出
+package main
+
+import (
+	"context"
+	"log/slog"
+	"net/http"
+	"os"
+	"os/signal"
+	"syscall"
+	"time"
+
+	"github.com/gin-gonic/gin"
+	"github.com/joho/godotenv"
+
+	"github.com/kennethcheng/fuellog-api/internal/config"
+	"github.com/kennethcheng/fuellog-api/internal/middleware"
+	"github.com/kennethcheng/fuellog-api/pkg/apperror"
+)
+
+func main() {
+	// .env 加载失败不致命(可能是生产环境用环境变量注入)
+	if err := godotenv.Load(); err != nil && !os.IsNotExist(err) {
+		slog.Warn(".env load failed", "err", err)
+	}
+
+	cfg, err := config.Load()
+	if err != nil {
+		slog.Error("config load failed", "err", err)
+		os.Exit(1)
+	}
+	gin.SetMode(cfg.GinMode)
+	slog.SetDefault(slog.New(slog.NewTextHandler(os.Stdout, &slog.HandlerOptions{
+		Level: parseLogLevel(cfg.LogLevel),
+	})))
+
+	app := &application{cfg: cfg}
+
+	srv := &http.Server{
+		Addr:              cfg.ServerAddr,
+		Handler:           app.router(),
+		ReadHeaderTimeout: 10 * time.Second,
+	}
+
+	// 启动 + 优雅退出
+	go func() {
+		slog.Info("server starting", "addr", cfg.ServerAddr, "mode", cfg.GinMode)
+		if err := srv.ListenAndServe(); err != nil && err != http.ErrServerClosed {
+			slog.Error("server error", "err", err)
+			os.Exit(1)
+		}
+	}()
+
+	stop := make(chan os.Signal, 1)
+	signal.Notify(stop, syscall.SIGINT, syscall.SIGTERM)
+	<-stop
+
+	slog.Info("server shutting down")
+	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
+	defer cancel()
+	if err := srv.Shutdown(ctx); err != nil {
+		slog.Error("graceful shutdown failed", "err", err)
+		os.Exit(1)
+	}
+	slog.Info("server stopped")
+}
+
+// application 持有所有依赖,避免散落全局变量。
+type application struct {
+	cfg *config.Config
+}
+
+// router 构建并返回 Gin 引擎。
+// 当前阶段只暴露 /health;Phase 2 起逐步接 /api/vehicles、/api/refuels。
+func (a *application) router() *gin.Engine {
+	r := gin.New()
+	r.Use(
+		middleware.Recover(),
+		middleware.Logger(),
+		middleware.CORS(a.cfg.CORSOrigins),
+	)
+
+	r.NoRoute(func(c *gin.Context) {
+		c.JSON(http.StatusNotFound, gin.H{
+			"code":    apperror.CodeNotFound,
+			"message": "路径不存在: " + c.Request.URL.Path,
+		})
+	})
+
+	r.GET("/health", func(c *gin.Context) {
+		c.JSON(http.StatusOK, gin.H{
+			"status": "ok",
+			"time":   a.cfg.Now().In(a.cfg.Location()).Format(time.RFC3339),
+		})
+	})
+
+	// /api 路由组(Phase 2 起在此挂载业务路由)
+	api := r.Group("/api")
+	_ = api // 占位,避免未使用告警
+
+	return r
+}
+
+func parseLogLevel(s string) slog.Level {
+	switch s {
+	case "debug":
+		return slog.LevelDebug
+	case "warn":
+		return slog.LevelWarn
+	case "error":
+		return slog.LevelError
+	default:
+		return slog.LevelInfo
+	}
+}
diff --git a/fuellog-api/go.mod b/fuellog-api/go.mod
new file mode 100644
index 0000000..de1e017
--- /dev/null
+++ b/fuellog-api/go.mod
@@ -0,0 +1,37 @@
+module github.com/kennethcheng/fuellog-api
+
+go 1.26.0
+
+require (
+	github.com/gin-gonic/gin v1.10.0
+	github.com/joho/godotenv v1.5.1
+)
+
+require (
+	github.com/bytedance/sonic v1.11.6 // indirect
+	github.com/bytedance/sonic/loader v0.1.1 // indirect
+	github.com/cloudwego/base64x v0.1.4 // indirect
+	github.com/cloudwego/iasm v0.2.0 // indirect
+	github.com/gabriel-vasile/mimetype v1.4.3 // indirect
+	github.com/gin-contrib/sse v0.1.0 // indirect
+	github.com/go-playground/locales v0.14.1 // indirect
+	github.com/go-playground/universal-translator v0.18.1 // indirect
+	github.com/go-playground/validator/v10 v10.20.0 // indirect
+	github.com/goccy/go-json v0.10.2 // indirect
+	github.com/json-iterator/go v1.1.12 // indirect
+	github.com/klauspost/cpuid/v2 v2.2.7 // indirect
+	github.com/leodido/go-urn v1.4.0 // indirect
+	github.com/mattn/go-isatty v0.0.20 // indirect
+	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
+	github.com/modern-go/reflect2 v1.0.2 // indirect
+	github.com/pelletier/go-toml/v2 v2.2.2 // indirect
+	github.com/twitchyliquid64/golang-asm v0.15.1 // indirect
+	github.com/ugorji/go/codec v1.2.12 // indirect
+	golang.org/x/arch v0.8.0 // indirect
+	golang.org/x/crypto v0.57.0 // indirect
+	golang.org/x/net v0.59.0 // indirect
+	golang.org/x/sys v0.48.0 // indirect
+	golang.org/x/text v0.42.0 // indirect
+	google.golang.org/protobuf v1.34.1 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
+)
diff --git a/fuellog-api/go.sum b/fuellog-api/go.sum
new file mode 100644
index 0000000..4bf0def
--- /dev/null
+++ b/fuellog-api/go.sum
@@ -0,0 +1,91 @@
+github.com/bytedance/sonic v1.11.6 h1:oUp34TzMlL+OY1OUWxHqsdkgC/Zfc85zGqw9siXjrc0=
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+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
+nullprogram.com/x/optparse v1.0.0/go.mod h1:KdyPE+Igbe0jQUrVfMqDMeJQIJZEuyV7pjYmp6pbG50=
+rsc.io/pdf v0.1.1/go.mod h1:n8OzWcQ6Sp37PL01nO98y4iUCRdTGarVfzxY20ICaU4=
diff --git a/fuellog-api/internal/config/.gitkeep b/fuellog-api/internal/config/.gitkeep
new file mode 100644
index 0000000..e69de29
diff --git a/fuellog-api/internal/config/config.go b/fuellog-api/internal/config/config.go
new file mode 100644
index 0000000..3c984da
--- /dev/null
+++ b/fuellog-api/internal/config/config.go
@@ -0,0 +1,82 @@
+// Package config 提供从环境变量加载 FuelLog API 配置的能力。
+//
+// 加载顺序:
+//  1. 当前工作目录下的 .env(若存在),由 main 显式调用 godotenv.Load
+//  2. 进程环境变量(覆盖 .env)
+//
+// 所有字段都有合理的默认值,适合本地开发与容器部署。
+package config
+
+import (
+	"fmt"
+	"os"
+	"strconv"
+	"strings"
+	"time"
+)
+
+// Config 持有 API 启动所需的全部配置。
+type Config struct {
+	ServerAddr  string        // 监听地址,例如 ":8080"
+	GinMode     string        // gin 模式:debug | release | test
+	DBPath      string        // SQLite 文件路径
+	TimeZone    string        // IANA 时区,例如 "Asia/Shanghai"
+	LogLevel    string        // debug | info | warn | error
+	CORSOrigins []string      // 允许的跨域来源
+	Now         func() time.Time // 用于测试的时间源,生产为 time.Now
+}
+
+// Load 读取环境变量并返回填充好的 Config。
+// 调用方负责在调用本函数前先执行 godotenv.Load()。
+func Load() (*Config, error) {
+	cfg := &Config{
+		ServerAddr: getEnv("SERVER_ADDR", ":8080"),
+		GinMode:    getEnv("GIN_MODE", "debug"),
+		DBPath:     getEnv("DB_PATH", "./data/fuellog.db"),
+		TimeZone:   getEnv("TZ", "Asia/Shanghai"),
+		LogLevel:   getEnv("LOG_LEVEL", "info"),
+		Now:        time.Now,
+	}
+
+	origins := getEnv("CORS_ORIGINS", "*")
+	for _, o := range strings.Split(origins, ",") {
+		if o = strings.TrimSpace(o); o != "" {
+			cfg.CORSOrigins = append(cfg.CORSOrigins, o)
+		}
+	}
+
+	if _, err := time.LoadLocation(cfg.TimeZone); err != nil {
+		return nil, fmt.Errorf("invalid TZ %q: %w", cfg.TimeZone, err)
+	}
+
+	switch cfg.GinMode {
+	case "debug", "release", "test":
+	default:
+		return nil, fmt.Errorf("invalid GIN_MODE %q (debug|release|test)", cfg.GinMode)
+	}
+
+	return cfg, nil
+}
+
+// Location 返回配置时区对应的 *time.Location。
+func (c *Config) Location() *time.Location {
+	loc, _ := time.LoadLocation(c.TimeZone)
+	return loc
+}
+
+func getEnv(key, def string) string {
+	if v, ok := os.LookupEnv(key); ok && v != "" {
+		return v
+	}
+	return def
+}
+
+// getEnvInt 解析 int 环境变量,失败回退到默认值。
+func getEnvInt(key string, def int) int {
+	if v, ok := os.LookupEnv(key); ok && v != "" {
+		if n, err := strconv.Atoi(v); err == nil {
+			return n
+		}
+	}
+	return def
+}
diff --git a/fuellog-api/internal/dto/.gitkeep b/fuellog-api/internal/dto/.gitkeep
new file mode 100644
index 0000000..e69de29
diff --git a/fuellog-api/internal/handler/.gitkeep b/fuellog-api/internal/handler/.gitkeep
new file mode 100644
index 0000000..e69de29
diff --git a/fuellog-api/internal/middleware/.gitkeep b/fuellog-api/internal/middleware/.gitkeep
new file mode 100644
index 0000000..e69de29
diff --git a/fuellog-api/internal/middleware/cors.go b/fuellog-api/internal/middleware/cors.go
new file mode 100644
index 0000000..65aad33
--- /dev/null
+++ b/fuellog-api/internal/middleware/cors.go
@@ -0,0 +1,44 @@
+package middleware
+
+import (
+	"github.com/gin-gonic/gin"
+)
+
+// CORS 返回一个允许指定来源跨域的中间件。
+// 允许 origins 包含 "*" 时回显 *,否则回显请求 Origin 并放行对应来源。
+func CORS(allowedOrigins []string) gin.HandlerFunc {
+	allowAll := false
+	originSet := make(map[string]struct{}, len(allowedOrigins))
+	for _, o := range allowedOrigins {
+		if o == "*" {
+			allowAll = true
+			continue
+		}
+		originSet[o] = struct{}{}
+	}
+	return func(c *gin.Context) {
+		origin := c.GetHeader("Origin")
+		if origin == "" {
+			c.Next()
+			return
+		}
+		if allowAll {
+			c.Header("Access-Control-Allow-Origin", "*")
+		} else if _, ok := originSet[origin]; ok {
+			c.Header("Access-Control-Allow-Origin", origin)
+			c.Header("Vary", "Origin")
+		} else {
+			c.Next()
+			return
+		}
+		c.Header("Access-Control-Allow-Methods", "GET,POST,PUT,PATCH,DELETE,OPTIONS")
+		c.Header("Access-Control-Allow-Headers", "Content-Type,Authorization,X-Requested-With")
+		c.Header("Access-Control-Max-Age", "86400")
+
+		if c.Request.Method == "OPTIONS" {
+			c.AbortWithStatus(204)
+			return
+		}
+		c.Next()
+	}
+}
diff --git a/fuellog-api/internal/middleware/logger.go b/fuellog-api/internal/middleware/logger.go
new file mode 100644
index 0000000..9a63160
--- /dev/null
+++ b/fuellog-api/internal/middleware/logger.go
@@ -0,0 +1,25 @@
+// Package middleware 提供 Gin 中间件:请求日志、panic 恢复、跨域。
+package middleware
+
+import (
+	"log/slog"
+	"time"
+
+	"github.com/gin-gonic/gin"
+)
+
+// Logger 打印每个 HTTP 请求的方法、路径、状态、耗时与客户端 IP。
+func Logger() gin.HandlerFunc {
+	return func(c *gin.Context) {
+		start := time.Now()
+		c.Next()
+		slog.Info("http",
+			"method", c.Request.Method,
+			"path", c.Request.URL.Path,
+			"status", c.Writer.Status(),
+			"size", c.Writer.Size(),
+			"duration_ms", time.Since(start).Milliseconds(),
+			"client_ip", c.ClientIP(),
+		)
+	}
+}
diff --git a/fuellog-api/internal/middleware/recover.go b/fuellog-api/internal/middleware/recover.go
new file mode 100644
index 0000000..0d48099
--- /dev/null
+++ b/fuellog-api/internal/middleware/recover.go
@@ -0,0 +1,33 @@
+package middleware
+
+import (
+	"log/slog"
+	"net/http"
+	"runtime/debug"
+
+	"github.com/gin-gonic/gin"
+
+	"github.com/kennethcheng/fuellog-api/pkg/apperror"
+)
+
+// Recover 捕获 handler 中的 panic,返回统一的 500 错误响应。
+// 同时把堆栈写入日志,便于定位。
+func Recover() gin.HandlerFunc {
+	return func(c *gin.Context) {
+		defer func() {
+			if r := recover(); r != nil {
+				slog.Error("panic recovered",
+					"path", c.Request.URL.Path,
+					"method", c.Request.Method,
+					"panic", r,
+					"stack", string(debug.Stack()),
+				)
+				c.AbortWithStatusJSON(http.StatusInternalServerError, gin.H{
+					"code":    apperror.CodeInternal,
+					"message": "服务器开了小差,请稍后再试",
+				})
+			}
+		}()
+		c.Next()
+	}
+}
diff --git a/fuellog-api/internal/model/.gitkeep b/fuellog-api/internal/model/.gitkeep
new file mode 100644
index 0000000..e69de29
diff --git a/fuellog-api/internal/repository/.gitkeep b/fuellog-api/internal/repository/.gitkeep
new file mode 100644
index 0000000..e69de29
diff --git a/fuellog-api/internal/router/.gitkeep b/fuellog-api/internal/router/.gitkeep
new file mode 100644
index 0000000..e69de29
diff --git a/fuellog-api/internal/service/.gitkeep b/fuellog-api/internal/service/.gitkeep
new file mode 100644
index 0000000..e69de29
diff --git a/fuellog-api/migrations/.gitkeep b/fuellog-api/migrations/.gitkeep
new file mode 100644
index 0000000..e69de29
diff --git a/fuellog-api/pkg/apperror/.gitkeep b/fuellog-api/pkg/apperror/.gitkeep
new file mode 100644
index 0000000..e69de29
diff --git a/fuellog-api/pkg/apperror/apperror.go b/fuellog-api/pkg/apperror/apperror.go
new file mode 100644
index 0000000..fb4e4ba
--- /dev/null
+++ b/fuellog-api/pkg/apperror/apperror.go
@@ -0,0 +1,94 @@
+// Package apperror 定义 FuelLog API 统一错误类型与错误码。
+//
+// 设计目标:
+//   - Handler / Service / Repository 各层都能用 errors.Is / errors.As 判定错误
+//   - 序列化为 FuelLog 约定的 JSON 错误响应:{ "code": "...", "message": "..." }
+//   - 错误码稳定、可被前端 i18n 映射
+package apperror
+
+import (
+	"errors"
+	"fmt"
+	"net/http"
+)
+
+// Code 是稳定的、可枚举的错误码。
+type Code string
+
+const (
+	CodeInternal       Code = "INTERNAL"         // 兜底 500,未预期
+	CodeInvalidArg     Code = "INVALID_ARGUMENT" // 参数校验失败 400
+	CodeNotFound       Code = "NOT_FOUND"        // 资源不存在 404
+	CodeConflict       Code = "CONFLICT"         // 资源冲突 409
+	CodeUnauthorized   Code = "UNAUTHORIZED"     // 401(预留)
+	CodeForbidden      Code = "FORBIDDEN"        // 403(预留)
+	CodeUnavailable    Code = "UNAVAILABLE"      // 503(预留)
+)
+
+// Error 是 FuelLog 的统一错误类型。
+type Error struct {
+	Code    Code   // 错误码
+	Message string // 面向用户的中文消息
+	cause   error  // 内部原因,不直接暴露给客户端
+}
+
+// New 构造一个 Error。
+func New(code Code, message string) *Error {
+	return &Error{Code: code, Message: message}
+}
+
+// Wrap 包装一个底层错误,保留链路。
+func Wrap(code Code, message string, cause error) *Error {
+	return &Error{Code: code, Message: message, cause: cause}
+}
+
+// Error 实现 error 接口。
+func (e *Error) Error() string {
+	if e.cause != nil {
+		return fmt.Sprintf("%s: %s: %v", e.Code, e.Message, e.cause)
+	}
+	return fmt.Sprintf("%s: %s", e.Code, e.Message)
+}
+
+// Unwrap 让 errors.Is / errors.As 能穿透到 cause。
+func (e *Error) Unwrap() error { return e.cause }
+
+// HTTPStatus 返回该错误对应的 HTTP 状态码。
+func (e *Error) HTTPStatus() int {
+	switch e.Code {
+	case CodeInvalidArg:
+		return http.StatusBadRequest
+	case CodeNotFound:
+		return http.StatusNotFound
+	case CodeConflict:
+		return http.StatusConflict
+	case CodeUnauthorized:
+		return http.StatusUnauthorized
+	case CodeForbidden:
+		return http.StatusForbidden
+	case CodeUnavailable:
+		return http.StatusServiceUnavailable
+	default:
+		return http.StatusInternalServerError
+	}
+}
+
+// Cause 返回底层错误,可能为 nil。
+func (e *Error) Cause() error { return e.cause }
+
+// As 是 errors.As 的便捷封装,用于在调用栈中提取 *Error。
+func As(err error) (*Error, bool) {
+	var e *Error
+	if errors.As(err, &e) {
+		return e, true
+	}
+	return nil, false
+}
+
+// IsCode 判定 err 链中是否包含指定错误码。
+func IsCode(err error, code Code) bool {
+	if e, ok := As(err); ok {
+		return e.Code == code
+	}
+	return false
+}
diff --git a/fuellog-api/pkg/decimal/.gitkeep b/fuellog-api/pkg/decimal/.gitkeep
new file mode 100644
index 0000000..e69de29