diff --git a/tests/unit/domain/test_auth_ports.py b/tests/unit/domain/test_auth_ports.py
new file mode 100755
index 000000000..68d38267e
--- /dev/null
+++ b/tests/unit/domain/test_auth_ports.py
@@ -0,0 +1,159 @@
+"""Auth ports (ABC接口) 单元测试.
+
+验证抽象接口定义正确：不能直接实例化，子类必须实现所有抽象方法。
+"""
+
+from __future__ import annotations
+
+from abc import ABC
+
+import pytest
+from domain.auth.email_service import EmailServicePort
+from domain.auth.jwt_service import JWTServicePort
+from domain.auth.password_hasher import PasswordHasherPort, PasswordValidatorPort
+from domain.auth.session_store import SessionStorePort
+from domain.auth.sms_service import SmsService
+
+
+class TestSessionStorePort:
+    """SessionStorePort 接口测试."""
+
+    def test_is_abstract(self):
+        assert issubclass(SessionStorePort, ABC)
+
+    def test_cannot_instantiate(self):
+        with pytest.raises(TypeError):
+            SessionStorePort()  # type: ignore[misc]
+
+    def test_has_abstract_methods(self):
+        abstract_methods = SessionStorePort.__abstractmethods__
+        expected = {
+            "save_session",
+            "get_session",
+            "get_session_by_refresh_token",
+            "get_refresh_token",
+            "update_last_active",
+            "delete_session",
+            "get_user_sessions",
+            "delete_all_user_sessions",
+            "session_exists",
+        }
+        assert expected.issubset(abstract_methods)
+
+    def test_concrete_subclass_works(self):
+        class ConcreteStore(SessionStorePort):
+            def save_session(self, **kwargs):  # type: ignore[override]
+                return True
+
+            def get_session(self, session_id):  # type: ignore[override]
+                return None
+
+            def get_session_by_refresh_token(self, token):  # type: ignore[override]
+                return None
+
+            def get_refresh_token(self, session_id):  # type: ignore[override]
+                return None
+
+            def update_last_active(self, session_id):  # type: ignore[override]
+                return True
+
+            def delete_session(self, session_id):  # type: ignore[override]
+                return True
+
+            def get_user_sessions(self, user_id):  # type: ignore[override]
+                return []
+
+            def delete_all_user_sessions(self, user_id):  # type: ignore[override]
+                return 0
+
+            def session_exists(self, session_id):  # type: ignore[override]
+                return False
+
+        store = ConcreteStore()
+        assert isinstance(store, SessionStorePort)
+        assert store.session_exists("s1") is False
+        assert store.delete_session("s1") is True
+
+
+class TestEmailServicePort:
+    """EmailServicePort 接口测试."""
+
+    def test_is_abstract(self):
+        assert issubclass(EmailServicePort, ABC)
+
+    def test_cannot_instantiate(self):
+        with pytest.raises(TypeError):
+            EmailServicePort()  # type: ignore[misc]
+
+    def test_has_abstract_methods(self):
+        abstract_methods = EmailServicePort.__abstractmethods__
+        expected = {"send_email", "send_verification_email", "send_password_reset_email"}
+        assert expected.issubset(abstract_methods)
+
+
+class TestJWTServicePort:
+    """JWTServicePort 接口测试."""
+
+    def test_is_abstract(self):
+        assert issubclass(JWTServicePort, ABC)
+
+    def test_cannot_instantiate(self):
+        with pytest.raises(TypeError):
+            JWTServicePort()  # type: ignore[misc]
+
+    def test_has_abstract_methods(self):
+        abstract_methods = JWTServicePort.__abstractmethods__
+        expected = {
+            "create_access_token",
+            "create_refresh_token",
+            "verify_token",
+            "verify_access_token",
+            "verify_refresh_token",
+        }
+        assert expected.issubset(abstract_methods)
+
+
+class TestPasswordHasherPort:
+    """PasswordHasherPort 接口测试."""
+
+    def test_is_abstract(self):
+        assert issubclass(PasswordHasherPort, ABC)
+
+    def test_cannot_instantiate(self):
+        with pytest.raises(TypeError):
+            PasswordHasherPort()  # type: ignore[misc]
+
+    def test_has_abstract_methods(self):
+        abstract_methods = PasswordHasherPort.__abstractmethods__
+        expected = {"hash_password", "verify_password", "needs_rehash"}
+        assert expected.issubset(abstract_methods)
+
+
+class TestPasswordValidatorPort:
+    """PasswordValidatorPort 接口测试."""
+
+    def test_is_abstract(self):
+        assert issubclass(PasswordValidatorPort, ABC)
+
+    def test_cannot_instantiate(self):
+        with pytest.raises(TypeError):
+            PasswordValidatorPort()  # type: ignore[misc]
+
+    def test_has_validate_method(self):
+        assert "validate" in PasswordValidatorPort.__abstractmethods__
+
+
+class TestSmsService:
+    """SmsService 接口测试."""
+
+    def test_is_abstract(self):
+        assert issubclass(SmsService, ABC)
+
+    def test_cannot_instantiate(self):
+        with pytest.raises(TypeError):
+            SmsService()  # type: ignore[misc]
+
+    def test_has_abstract_methods(self):
+        abstract_methods = SmsService.__abstractmethods__
+        expected = {"send_verification_code", "send_template_sms"}
+        assert expected.issubset(abstract_methods)
diff --git a/tests/unit/domain/test_bgm_utils.py b/tests/unit/domain/test_bgm_utils.py
new file mode 100755
index 000000000..6bc3878cd
--- /dev/null
+++ b/tests/unit/domain/test_bgm_utils.py
@@ -0,0 +1,139 @@
+"""bgm_utils 单元测试."""
+
+from __future__ import annotations
+
+from domain.bgm_utils import merge_bgm_config
+
+
+class TestMergeBgmConfigEmptyInputs:
+    """空输入测试."""
+
+    def test_both_empty(self):
+        result = merge_bgm_config({}, {})
+        assert result == {}
+
+    def test_user_empty_returns_template_copy(self):
+        template = {"enabled": True, "volume": 0.5}
+        result = merge_bgm_config(template, {})
+        assert result == {"enabled": True, "volume": 0.5}
+        # 返回的是副本不是同一个对象
+        assert result is not template
+
+    def test_template_empty_returns_user_copy(self):
+        user = {"enabled": False, "volume": 0.8}
+        result = merge_bgm_config({}, user)
+        assert result == {"enabled": False, "volume": 0.8}
+        assert result is not user
+
+    def test_user_none_returns_template(self):
+        template = {"enabled": True}
+        result = merge_bgm_config(template, None)  # type: ignore[arg-type]
+        assert result == template
+
+    def test_template_none_returns_user(self):
+        user = {"enabled": True}
+        result = merge_bgm_config(None, user)  # type: ignore[arg-type]
+        assert result == user
+
+
+class TestMergeBgmConfigBasicMerge:
+    """基础合并测试."""
+
+    def test_user_overrides_template_field(self):
+        template = {"volume": 0.5, "fade_in": 1.0}
+        user = {"volume": 0.8}
+        result = merge_bgm_config(template, user)
+        assert result["volume"] == 0.8
+        assert result["fade_in"] == 1.0
+
+    def test_user_adds_new_field(self):
+        template = {"volume": 0.5}
+        user = {"fade_out": 2.0}
+        result = merge_bgm_config(template, user)
+        assert result["volume"] == 0.5
+        assert result["fade_out"] == 2.0
+
+    def test_all_fields_overridden(self):
+        template = {"enabled": True, "volume": 0.5, "track_id": "t1"}
+        user = {"enabled": False, "volume": 1.0, "track_id": "t2"}
+        result = merge_bgm_config(template, user)
+        assert result == {"enabled": False, "volume": 1.0, "track_id": "t2"}
+
+
+class TestMergeBgmConfigEnabledSpecial:
+    """enabled 特殊处理测试."""
+
+    def test_user_no_enabled_keeps_template_enabled_true(self):
+        template = {"enabled": True, "volume": 0.5}
+        user = {"volume": 0.8}
+        result = merge_bgm_config(template, user)
+        assert result["enabled"] is True
+        assert result["volume"] == 0.8
+
+    def test_user_no_enabled_keeps_template_enabled_false(self):
+        template = {"enabled": False, "volume": 0.5}
+        user = {"volume": 0.8}
+        result = merge_bgm_config(template, user)
+        assert result["enabled"] is False
+        assert result["volume"] == 0.8
+
+    def test_user_explicit_enabled_true_overrides_template_false(self):
+        template = {"enabled": False, "volume": 0.5}
+        user = {"enabled": True, "volume": 0.8}
+        result = merge_bgm_config(template, user)
+        assert result["enabled"] is True
+        assert result["volume"] == 0.8
+
+    def test_user_explicit_enabled_false_overrides_template_true(self):
+        template = {"enabled": True, "volume": 0.5}
+        user = {"enabled": False}
+        result = merge_bgm_config(template, user)
+        assert result["enabled"] is False
+
+    def test_template_no_enabled_user_no_enabled(self):
+        template = {"volume": 0.5}
+        user = {"volume": 0.8}
+        result = merge_bgm_config(template, user)
+        assert "enabled" not in result
+        assert result["volume"] == 0.8
+
+    def test_template_no_enabled_user_has_enabled(self):
+        template = {"volume": 0.5}
+        user = {"enabled": True, "volume": 0.8}
+        result = merge_bgm_config(template, user)
+        assert result["enabled"] is True
+
+
+class TestMergeBgmConfigDoesNotMutate:
+    """不修改原字典测试."""
+
+    def test_template_not_mutated(self):
+        template = {"enabled": True, "volume": 0.5}
+        original = dict(template)
+        user = {"volume": 0.8, "fade": 1.0}
+        merge_bgm_config(template, user)
+        assert template == original
+
+    def test_user_not_mutated(self):
+        template = {"enabled": True, "volume": 0.5}
+        user = {"volume": 0.8}
+        original = dict(user)
+        merge_bgm_config(template, user)
+        assert user == original
+
+
+class TestMergeBgmConfigNestedDict:
+    """嵌套字典合并测试（简单合并，非深合并）."""
+
+    def test_nested_dict_user_overrides(self):
+        template = {"effects": {"fade_in": 1.0, "fade_out": 1.0}}
+        user = {"effects": {"fade_in": 2.0}}
+        result = merge_bgm_config(template, user)
+        # 简单合并，用户effects整个覆盖模板的
+        assert result["effects"] == {"fade_in": 2.0}
+
+    def test_nested_dict_preserved_when_no_user_override(self):
+        template = {"effects": {"fade_in": 1.0}}
+        user = {"volume": 0.8}
+        result = merge_bgm_config(template, user)
+        assert result["effects"] == {"fade_in": 1.0}
diff --git a/tests/unit/domain/test_email_config.py b/tests/unit/domain/test_email_config.py
new file mode 100755
index 000000000..945c400c5
--- /dev/null
+++ b/tests/unit/domain/test_email_config.py
@@ -0,0 +1,63 @@
+"""EmailConfig 单元测试."""
+
+from __future__ import annotations
+
+import pytest
+from domain.auth.email_service import EmailConfig
+
+
+class TestEmailConfigDefaults:
+    """默认值测试."""
+
+    def test_default_values(self):
+        config = EmailConfig()
+        assert config.smtp_host == "smtp.gmail.com"
+        assert config.smtp_port == 587
+        assert config.smtp_user == ""
+        assert config.smtp_password == ""
+        assert config.from_email == ""
+        assert config.from_name == "小虾 SaaS"
+        assert config.use_tls is True
+
+    def test_custom_construction(self):
+        config = EmailConfig(
+            smtp_host="smtp.example.com",
+            smtp_port=465,
+            smtp_user="user@example.com",
+            smtp_password="secret",
+            from_email="no-reply@example.com",
+            from_name="Example App",
+            use_tls=False,
+        )
+        assert config.smtp_host == "smtp.example.com"
+        assert config.smtp_port == 465
+        assert config.smtp_user == "user@example.com"
+        assert config.smtp_password == "secret"
+        assert config.from_email == "no-reply@example.com"
+        assert config.from_name == "Example App"
+        assert config.use_tls is False
+
+    def test_is_dataclass(self):
+        # 可重复创建相同配置
+        c1 = EmailConfig(smtp_host="h.com", smtp_port=25)
+        c2 = EmailConfig(smtp_host="h.com", smtp_port=25)
+        assert c1 == c2
+
+
+class TestEmailConfigEquality:
+    """相等性测试."""
+
+    def test_equal_same_values(self):
+        c1 = EmailConfig()
+        c2 = EmailConfig()
+        assert c1 == c2
+
+    def test_not_equal_different_host(self):
+        c1 = EmailConfig(smtp_host="a.com")
+        c2 = EmailConfig(smtp_host="b.com")
+        assert c1 != c2
+
+    def test_not_equal_different_port(self):
+        c1 = EmailConfig(smtp_port=587)
+        c2 = EmailConfig(smtp_port=465)
+        assert c1 != c2
diff --git a/tests/unit/domain/test_exceptions.py b/tests/unit/domain/test_exceptions.py
new file mode 100755
index 000000000..fd10be63c
--- /dev/null
+++ b/tests/unit/domain/test_exceptions.py
@@ -0,0 +1,107 @@
+"""domain exceptions 单元测试."""
+
+from __future__ import annotations
+
+import pytest
+from domain.exceptions import (
+    DomainError,
+    NotFoundError,
+    QuotaExceededError,
+    ValidationError,
+)
+
+
+class TestDomainError:
+    """DomainError 基类测试."""
+
+    def test_is_exception(self):
+        assert issubclass(DomainError, Exception)
+
+    def test_raise_and_catch(self):
+        with pytest.raises(DomainError):
+            raise DomainError("something went wrong")
+
+    def test_message(self):
+        err = DomainError("test message")
+        assert str(err) == "test message"
+
+    def test_empty_message(self):
+        err = DomainError()
+        assert str(err) == ""
+
+
+class TestNotFoundError:
+    """NotFoundError 测试."""
+
+    def test_is_domain_error(self):
+        assert issubclass(NotFoundError, DomainError)
+
+    def test_raise_and_catch_as_domain(self):
+        with pytest.raises(DomainError):
+            raise NotFoundError("user not found")
+
+    def test_raise_and_catch_specific(self):
+        with pytest.raises(NotFoundError):
+            raise NotFoundError("user not found")
+
+    def test_message(self):
+        err = NotFoundError("resource not found")
+        assert str(err) == "resource not found"
+
+
+class TestValidationError:
+    """ValidationError 测试."""
+
+    def test_is_domain_error(self):
+        assert issubclass(ValidationError, DomainError)
+
+    def test_raise_and_catch_as_domain(self):
+        with pytest.raises(DomainError):
+            raise ValidationError("invalid input")
+
+    def test_raise_and_catch_specific(self):
+        with pytest.raises(ValidationError):
+            raise ValidationError("invalid input")
+
+    def test_message(self):
+        err = ValidationError("bad data")
+        assert str(err) == "bad data"
+
+
+class TestQuotaExceededError:
+    """QuotaExceededError 测试."""
+
+    def test_is_domain_error(self):
+        assert issubclass(QuotaExceededError, DomainError)
+
+    def test_constructor_stores_fields(self):
+        err = QuotaExceededError("storage", limit=100.0, used=150.0)
+        assert err.dimension == "storage"
+        assert err.limit == 100.0
+        assert err.used == 150.0
+
+    def test_message_format(self):
+        err = QuotaExceededError("storage", limit=100.0, used=150.0)
+        assert "storage" in str(err)
+        assert "150.0" in str(err)
+        assert "100.0" in str(err)
+        assert "Quota exceeded" in str(err)
+
+    def test_raise_and_catch_as_domain(self):
+        with pytest.raises(DomainError):
+            raise QuotaExceededError("api_calls", limit=1000, used=2000)
+
+    def test_raise_and_catch_specific(self):
+        with pytest.raises(QuotaExceededError):
+            raise QuotaExceededError("api_calls", limit=1000, used=2000)
+
+    def test_int_values(self):
+        err = QuotaExceededError("count", limit=100, used=150)
+        assert err.limit == 100
+        assert err.used == 150
+        assert "150/100" in str(err)
+
+    def test_float_values(self):
+        err = QuotaExceededError("size", limit=10.5, used=20.3)
+        assert err.limit == 10.5
+        assert err.used == 20.3
diff --git a/tests/unit/domain/test_template_version.py b/tests/unit/domain/test_template_version.py
new file mode 100755
index 000000000..5e3adcb7f
--- /dev/null
+++ b/tests/unit/domain/test_template_version.py
@@ -0,0 +1,134 @@
+"""EditTemplateVersion 单元测试."""
+
+from __future__ import annotations
+
+from datetime import datetime, timezone
+
+import pytest
+from domain.template_version import EditTemplateVersion
+
+
+class TestEditTemplateVersionCreate:
+    """create() 工厂方法测试."""
+
+    def test_create_basic(self):
+        v = EditTemplateVersion.create("tmpl_001", 1)
+        assert v.id is not None
+        assert len(v.id) == 32
+        assert v.template_id == "tmpl_001"
+        assert v.version == 1
+        assert v.name == ""
+        assert v.editing_mode == "one_take"
+        assert v.config == {}
+        assert v.clip_configs == []
+        assert v.change_note == ""
+        assert v.published_by == ""
+        assert v.created_at is not None
+
+    def test_create_with_all_fields(self):
+        v = EditTemplateVersion.create(
+            "tmpl_001",
+            3,
+            name="第三版",
+            editing_mode="pip",
+            config={"bgm": True},
+            clip_configs=[{"id": "c1", "type": "video"}],
+            change_note="优化剪辑逻辑",
+            published_by="user_123",
+        )
+        assert v.template_id == "tmpl_001"
+        assert v.version == 3
+        assert v.name == "第三版"
+        assert v.editing_mode == "pip"
+        assert v.config == {"bgm": True}
+        assert v.clip_configs == [{"id": "c1", "type": "video"}]
+        assert v.change_note == "优化剪辑逻辑"
+        assert v.published_by == "user_123"
+
+    def test_create_config_none_defaults_to_empty(self):
+        v = EditTemplateVersion.create("t1", 1, config=None)
+        assert v.config == {}
+
+    def test_create_clip_configs_none_defaults_to_empty(self):
+        v = EditTemplateVersion.create("t1", 1, clip_configs=None)
+        assert v.clip_configs == []
+
+    def test_create_unique_ids(self):
+        v1 = EditTemplateVersion.create("t1", 1)
+        v2 = EditTemplateVersion.create("t1", 1)
+        assert v1.id != v2.id
+
+    def test_create_sets_created_at(self):
+        before = datetime.now(timezone.utc)
+        v = EditTemplateVersion.create("t1", 1)
+        after = datetime.now(timezone.utc)
+        assert before <= v.created_at <= after
+
+
+class TestEditTemplateVersionConstruction:
+    """直接构造测试."""
+
+    def test_direct_construction(self):
+        now = datetime(2026, 1, 1, tzinfo=timezone.utc)
+        v = EditTemplateVersion(
+            id="v1",
+            template_id="t1",
+            version=5,
+            name="v5",
+            editing_mode="voice_over",
+            config={"key": "value"},
+            clip_configs=[{"a": 1}, {"b": 2}],
+            change_note="test",
+            published_by="admin",
+            created_at=now,
+        )
+        assert v.id == "v1"
+        assert v.template_id == "t1"
+        assert v.version == 5
+        assert v.name == "v5"
+        assert v.editing_mode == "voice_over"
+        assert v.config == {"key": "value"}
+        assert v.clip_configs == [{"a": 1}, {"b": 2}]
+        assert v.change_note == "test"
+        assert v.published_by == "admin"
+        assert v.created_at == now
+
+    def test_default_values(self):
+        v = EditTemplateVersion(id="v1", template_id="t1", version=1)
+        assert v.name == ""
+        assert v.editing_mode == "one_take"
+        assert v.config == {}
+        assert v.clip_configs == []
+        assert v.change_note == ""
+        assert v.published_by == ""
+
+
+class TestEditTemplateVersionSlots:
+    """slots 测试."""
+
+    def test_slots_no_extra_attrs(self):
+        v = EditTemplateVersion.create("t1", 1)
+        with pytest.raises((AttributeError, TypeError)):
+            v.new_field = "value"  # type: ignore[attr-defined]
+
+
+class TestEditTemplateVersionEquality:
+    """相等性测试."""
+
+    def test_equal_same_id_and_version(self):
+        now = datetime(2026, 1, 1, tzinfo=timezone.utc)
+        v1 = EditTemplateVersion(id="same", template_id="t1", version=1, created_at=now)
+        v2 = EditTemplateVersion(id="same", template_id="t1", version=1, created_at=now)
+        assert v1 == v2
+
+    def test_not_equal_different_id(self):
+        now = datetime(2026, 1, 1, tzinfo=timezone.utc)
+        v1 = EditTemplateVersion(id="v1", template_id="t1", version=1, created_at=now)
+        v2 = EditTemplateVersion(id="v2", template_id="t1", version=1, created_at=now)
+        assert v1 != v2
+
+    def test_not_equal_different_version(self):
+        now = datetime(2026, 1, 1, tzinfo=timezone.utc)
+        v1 = EditTemplateVersion(id="same", template_id="t1", version=1, created_at=now)
+        v2 = EditTemplateVersion(id="same", template_id="t1", version=2, created_at=now)
+        assert v1 != v2