diff --git a/backend/internal/ghost/ghost.go b/backend/internal/ghost/ghost.go
index d99c74a..d4564b4 100644
--- a/backend/internal/ghost/ghost.go
+++ b/backend/internal/ghost/ghost.go
@@ -13,6 +13,7 @@ import (
 // GhOstTask defines a gh-ost execution task
 type GhOstTask struct {
 	Host           string `json:"host"`
+	Port           int    `json:"port,omitempty"`
 	User           string `json:"user"`
 	Password       string `json:"password"`
 	Database       string `json:"database"`
@@ -60,12 +61,18 @@ func RunGhOst(ctx context.Context, task GhOstTask, ghOstPath string) (*GhOstResu
 
 	args := []string{
 		"--host=" + task.Host,
+		fmt.Sprintf("--port=%d", task.Port),
 		"--user=" + task.User,
 		"--password=" + task.Password,
 		"--database=" + task.Database,
 		"--table=" + task.Table,
 		"--alter=" + task.Alter,
 		"--verbose",
+		"--skip-port-validation",
+		"--allow-on-master",
+		"--initially-drop-ghost-table",
+		"--initially-drop-old-table",
+		"--initially-drop-socket-file",
 	}
 
 	if task.ChunkSize > 0 {
@@ -91,11 +98,11 @@ func RunGhOst(ctx context.Context, task GhOstTask, ghOstPath string) (*GhOstResu
 	}
 
 	// Dry-Run vs Execute
-	if task.DryRun || !task.Execute {
-		args = append(args, "--dry-run")
-	} else {
+	// gh-ost defaults to noop (dry-run), only --execute actually applies changes
+	if task.Execute {
 		args = append(args, "--execute")
 	}
+	// always verbose for output
 
 	cmd := exec.CommandContext(ctx, ghOstPath, args...)
 	var stdout, stderr bytes.Buffer
@@ -193,12 +200,18 @@ func (m *TaskManager) ListTasks() map[string]string {
 func buildArgs(task GhOstTask, ghOstPath string) []string {
 	args := []string{
 		"--host=" + task.Host,
+		fmt.Sprintf("--port=%d", task.Port),
 		"--user=" + task.User,
 		"--password=" + task.Password,
 		"--database=" + task.Database,
 		"--table=" + task.Table,
 		"--alter=" + task.Alter,
 		"--verbose",
+		"--skip-port-validation",
+		"--allow-on-master",
+		"--initially-drop-ghost-table",
+		"--initially-drop-old-table",
+		"--initially-drop-socket-file",
 	}
 
 	if task.ChunkSize > 0 {
@@ -223,9 +236,8 @@ func buildArgs(task GhOstTask, ghOstPath string) []string {
 		args = append(args, "--postpone-cut-over-flag-file=/tmp/gh-ost-cutover.flag")
 	}
 
-	if task.DryRun || !task.Execute {
-		args = append(args, "--dry-run")
-	} else {
+	// gh-ost defaults to noop, only --execute actually applies changes
+	if task.Execute {
 		args = append(args, "--execute")
 	}
 
diff --git a/backend/internal/handler/ghost.go b/backend/internal/handler/ghost.go
index 4f6f523..f06270e 100644
--- a/backend/internal/handler/ghost.go
+++ b/backend/internal/handler/ghost.go
@@ -1,6 +1,7 @@
 package handler
 
 import (
+	"fmt"
 	"net/http"
 	"time"
 
@@ -13,15 +14,27 @@ import (
 
 // POST /api/v1/ghost/dry-run
 func GhOstDryRun(c *gin.Context) {
-	var task ghost.GhOstTask
-	if err := c.ShouldBindJSON(&task); err != nil {
+	var req struct {
+		InstanceID int    `json:"instance_id"`
+		Database   string `json:"database"`
+		Table      string `json:"table"`
+		Alter      string `json:"alter"`
+	}
+	if err := c.ShouldBindJSON(&req); err != nil {
+		c.JSON(http.StatusBadRequest, gin.H{"detail": err.Error()})
+		return
+	}
+
+	// Look up instance connection info
+	task, err := buildGhOstTask(req.InstanceID, req.Database, req.Table, req.Alter)
+	if err != nil {
 		c.JSON(http.StatusBadRequest, gin.H{"detail": err.Error()})
 		return
 	}
 	task.DryRun = true
 	task.Execute = false
 
-	result, err := ghost.RunGhOst(c.Request.Context(), task, config.C.GhOstPath)
+	result, err := ghost.RunGhOst(c.Request.Context(), *task, config.C.GhOstPath)
 	if err != nil {
 		c.JSON(http.StatusInternalServerError, result)
 		return
@@ -29,17 +42,51 @@ func GhOstDryRun(c *gin.Context) {
 	c.JSON(http.StatusOK, result)
 }
 
+// buildGhOstTask resolves instance_id to connection params
+func buildGhOstTask(instanceID int, database, table, alter string) (*ghost.GhOstTask, error) {
+	var inst model.Instance
+	if err := model.DB.First(&inst, instanceID).Error; err != nil {
+		return nil, fmt.Errorf("instance %d not found", instanceID)
+	}
+	if inst.DBType != "mysql" {
+		return nil, fmt.Errorf("gh-ost only supports MySQL instances, got %s", inst.DBType)
+	}
+	// gh-ost needs separate host and port
+	host := inst.Host
+	port := inst.Port
+	return &ghost.GhOstTask{
+		Host:     host,
+		Port:     port,
+		User:     inst.Username,
+		Password: inst.Password,
+		Database: database,
+		Table:    table,
+		Alter:    alter,
+	}, nil
+}
+
 // POST /api/v1/ghost/execute
 func GhOstExecute(c *gin.Context) {
-	var task ghost.GhOstTask
-	if err := c.ShouldBindJSON(&task); err != nil {
+	var req struct {
+		InstanceID int    `json:"instance_id"`
+		Database   string `json:"database"`
+		Table      string `json:"table"`
+		Alter      string `json:"alter"`
+	}
+	if err := c.ShouldBindJSON(&req); err != nil {
+		c.JSON(http.StatusBadRequest, gin.H{"detail": err.Error()})
+		return
+	}
+
+	task, err := buildGhOstTask(req.InstanceID, req.Database, req.Table, req.Alter)
+	if err != nil {
 		c.JSON(http.StatusBadRequest, gin.H{"detail": err.Error()})
 		return
 	}
 	task.DryRun = false
 	task.Execute = true
 
-	taskID := ghost.RunGhOstAsync(task, config.C.GhOstPath, nil)
+	taskID := ghost.RunGhOstAsync(*task, config.C.GhOstPath, nil)
 	c.JSON(http.StatusAccepted, gin.H{
 		"task_id": taskID,
 		"message": "gh-ost execution started",
diff --git a/backend/internal/handler/preferences.go b/backend/internal/handler/preferences.go
index 8884dbb..bf2cb66 100644
--- a/backend/internal/handler/preferences.go
+++ b/backend/internal/handler/preferences.go
@@ -43,26 +43,41 @@ func UpdateUserPreferences(c *gin.Context) {
 		c.JSON(http.StatusInternalServerError, gin.H{"detail": result.Error.Error()})
 		return
 	}
+
+	// Sync login_style and theme to SystemSetting so public endpoint picks them up
+	syncToSystemSetting := func(key, value string) {
+		var s model.SystemSetting
+		if model.DB.Where("`key` = ?", key).First(&s).Error == nil {
+			model.DB.Model(&s).Update("value", value)
+		} else {
+			model.DB.Create(&model.SystemSetting{
+				Key: key, Value: value, ValueType: "string",
+				Group: "appearance", Label: key, SortOrder: 0,
+			})
+		}
+	}
+	if v, ok := prefs["login_style"]; ok {
+		syncToSystemSetting("login_style", v)
+	}
+	if v, ok := prefs["theme"]; ok {
+		syncToSystemSetting("default_theme", v)
+	}
+
 	c.JSON(http.StatusOK, gin.H{"message": "Preferences updated", "preferences": prefs})
 }
 
 // GET /api/v1/public/login-style (no auth required)
 func GetPublicLoginStyle(c *gin.Context) {
-	// Check system settings first
-	var setting model.SystemSetting
-	style := "split" // default
-	if model.DB.Where("`key` = ?", "login_style").First(&setting).Error == nil {
-		if setting.Value != "" {
-			style = setting.Value
-		}
-	}
-
-	// Also return theme default
+	style := "split"
 	theme := "dark"
-	if model.DB.Where("`key` = ?", "default_theme").First(&setting).Error == nil {
-		if setting.Value != "" {
-			theme = setting.Value
-		}
+
+	var s model.SystemSetting
+	if model.DB.Where("`key` = ?", "login_style").Take(&s).Error == nil && s.Value != "" {
+		style = s.Value
+	}
+	s = model.SystemSetting{} // reset to avoid GORM reusing primary key
+	if model.DB.Where("`key` = ?", "default_theme").Take(&s).Error == nil && s.Value != "" {
+		theme = s.Value
 	}
 
 	c.JSON(http.StatusOK, gin.H{"login_style": style, "theme": theme})
diff --git a/frontend/src/components/login/CenteredCard.tsx b/frontend/src/components/login/CenteredCard.tsx
index 1343cd9..62940ac 100644
--- a/frontend/src/components/login/CenteredCard.tsx
+++ b/frontend/src/components/login/CenteredCard.tsx
@@ -23,9 +23,9 @@ export default function CenteredCard() {
       <div style={{ position: 'relative', zIndex: 10, width: '100%', maxWidth: 400, background: 'var(--dg-bg-primary)', borderRadius: 14, padding: '40px 32px', boxShadow: '0 8px 32px rgba(0,0,0,0.3)' }}>
         <div style={{ textAlign: 'center', marginBottom: 32 }}>
           <h1 style={{ fontSize: 24, fontWeight: 700, marginBottom: 6 }}>
-            <span className="dg-gradient-text">SQL Audit Platform</span>
+            <span className="dg-gradient-text">SQL审核平台</span>
           </h1>
-          <p style={{ color: 'var(--dg-text-muted)', fontSize: 14 }}>Sign in to your account</p>
+          <p style={{ color: 'var(--dg-text-muted)', fontSize: 14 }}>登录您的账号</p>
         </div>
 
         <form onSubmit={handleLogin} style={{ display: 'flex', flexDirection: 'column', gap: 16 }}>
@@ -33,14 +33,14 @@ export default function CenteredCard() {
 
           <input
             type="text"
-            placeholder="Username"
+            placeholder="用户名"
             value={username}
             onChange={(e) => setUsername(e.target.value)}
             style={{ padding: '11px 14px', borderRadius: 8, background: 'var(--dg-bg-secondary)', border: '1px solid var(--dg-border)', color: 'var(--dg-text-primary)', fontSize: 14, outline: 'none' }}
           />
           <input
             type="password"
-            placeholder="Password"
+            placeholder="密码"
             value={password}
             onChange={(e) => setPassword(e.target.value)}
             style={{ padding: '11px 14px', borderRadius: 8, background: 'var(--dg-bg-secondary)', border: '1px solid var(--dg-border)', color: 'var(--dg-text-primary)', fontSize: 14, outline: 'none' }}
@@ -52,7 +52,7 @@ export default function CenteredCard() {
             className="dg-gradient-bg"
             style={{ padding: '11px 14px', borderRadius: 8, border: 'none', color: '#fff', fontWeight: 600, fontSize: 14, cursor: loading || !username || !password ? 'not-allowed' : 'pointer', opacity: loading || !username || !password ? 0.6 : 1, marginTop: 4 }}
           >
-            {loading ? 'Signing in…' : 'Sign in'}
+            {loading ? '登录中…' : '登录'}
           </button>
         </form>
       </div>
diff --git a/frontend/src/components/login/FullImage.tsx b/frontend/src/components/login/FullImage.tsx
index 1f560f1..b2ce634 100644
--- a/frontend/src/components/login/FullImage.tsx
+++ b/frontend/src/components/login/FullImage.tsx
@@ -40,9 +40,9 @@ export default function FullImage() {
       >
         <div style={{ textAlign: 'center', marginBottom: 32 }}>
           <h1 style={{ fontSize: 24, fontWeight: 700, marginBottom: 6 }}>
-            <span className="dg-gradient-text">SQL Audit Platform</span>
+            <span className="dg-gradient-text">SQL审核平台</span>
           </h1>
-          <p style={{ color: 'rgba(255,255,255,0.6)', fontSize: 14 }}>Sign in to your workspace</p>
+          <p style={{ color: 'rgba(255,255,255,0.6)', fontSize: 14 }}>登录您的工作区</p>
         </div>
 
         <form onSubmit={handleLogin} style={{ display: 'flex', flexDirection: 'column', gap: 16 }}>
@@ -50,14 +50,14 @@ export default function FullImage() {
 
           <input
             type="text"
-            placeholder="Username"
+            placeholder="用户名"
             value={username}
             onChange={(e) => setUsername(e.target.value)}
             style={{ padding: '11px 14px', borderRadius: 8, background: 'rgba(255,255,255,0.08)', border: '1px solid rgba(255,255,255,0.12)', color: '#fff', fontSize: 14, outline: 'none' }}
           />
           <input
             type="password"
-            placeholder="Password"
+            placeholder="密码"
             value={password}
             onChange={(e) => setPassword(e.target.value)}
             style={{ padding: '11px 14px', borderRadius: 8, background: 'rgba(255,255,255,0.08)', border: '1px solid rgba(255,255,255,0.12)', color: '#fff', fontSize: 14, outline: 'none' }}
@@ -69,7 +69,7 @@ export default function FullImage() {
             className="dg-gradient-bg"
             style={{ padding: '11px 14px', borderRadius: 8, border: 'none', color: '#fff', fontWeight: 600, fontSize: 14, cursor: loading || !username || !password ? 'not-allowed' : 'pointer', opacity: loading || !username || !password ? 0.6 : 1, marginTop: 4 }}
           >
-            {loading ? 'Signing in…' : 'Sign in'}
+            {loading ? '登录中…' : '登录'}
           </button>
         </form>
       </div>
diff --git a/frontend/src/components/login/MinimalDark.tsx b/frontend/src/components/login/MinimalDark.tsx
index 41be0d3..32f1840 100644
--- a/frontend/src/components/login/MinimalDark.tsx
+++ b/frontend/src/components/login/MinimalDark.tsx
@@ -18,23 +18,23 @@ export default function MinimalDark() {
       <div style={{ width: '100%', maxWidth: 320, textAlign: 'center' }}>
         <Database size={36} className="dg-gradient-text" style={{ marginBottom: 16, display: 'inline-block' }} />
         <h1 style={{ fontSize: 22, fontWeight: 700, marginBottom: 4 }}>
-          <span className="dg-gradient-text">SQL Audit Platform</span>
+          <span className="dg-gradient-text">SQL审核平台</span>
         </h1>
-        <p style={{ color: 'var(--dg-text-muted)', fontSize: 13, marginBottom: 36 }}>Secure database auditing & compliance</p>
+        <p style={{ color: 'var(--dg-text-muted)', fontSize: 13, marginBottom: 36 }}>安全的数据库审核与合规管理</p>
 
         <form onSubmit={handleLogin} style={{ display: 'flex', flexDirection: 'column', gap: 14 }}>
           {error && <div style={{ color: '#f87171', fontSize: 13 }}>{error}</div>}
 
           <input
             type="text"
-            placeholder="Username"
+            placeholder="用户名"
             value={username}
             onChange={(e) => setUsername(e.target.value)}
             style={{ padding: '10px 14px', borderRadius: 8, background: 'var(--dg-bg-secondary)', border: 'none', color: 'var(--dg-text-primary)', fontSize: 14, outline: 'none' }}
           />
           <input
             type="password"
-            placeholder="Password"
+            placeholder="密码"
             value={password}
             onChange={(e) => setPassword(e.target.value)}
             style={{ padding: '10px 14px', borderRadius: 8, background: 'var(--dg-bg-secondary)', border: 'none', color: 'var(--dg-text-primary)', fontSize: 14, outline: 'none' }}
@@ -46,7 +46,7 @@ export default function MinimalDark() {
             className="dg-gradient-bg"
             style={{ padding: '10px 14px', borderRadius: 8, border: 'none', color: '#fff', fontWeight: 600, fontSize: 14, cursor: loading || !username || !password ? 'not-allowed' : 'pointer', opacity: loading || !username || !password ? 0.6 : 1, marginTop: 8 }}
           >
-            {loading ? 'Signing in…' : 'Sign in'}
+            {loading ? '登录中…' : '登录'}
           </button>
         </form>
       </div>
diff --git a/frontend/src/components/login/SidePanel.tsx b/frontend/src/components/login/SidePanel.tsx
index 72cfbc7..427594a 100644
--- a/frontend/src/components/login/SidePanel.tsx
+++ b/frontend/src/components/login/SidePanel.tsx
@@ -29,9 +29,9 @@ export default function SidePanel() {
 
         <div style={{ position: 'relative', zIndex: 2, textAlign: 'center', maxWidth: 320 }}>
           <Database size={40} style={{ color: '#fff', marginBottom: 20 }} />
-          <h1 style={{ fontSize: 26, fontWeight: 700, color: '#fff', marginBottom: 12 }}>SQL Audit Platform</h1>
+          <h1 style={{ fontSize: 26, fontWeight: 700, color: '#fff', marginBottom: 12 }}>SQL审核平台</h1>
           <p style={{ color: 'rgba(255,255,255,0.7)', fontSize: 14, lineHeight: 1.6 }}>
-            Empowering teams with intelligent SQL auditing, real-time compliance monitoring, and actionable insights for database security.
+            为团队提供智能 SQL 审核、实时合规监控与数据库安全保障。
           </p>
         </div>
       </div>
@@ -39,21 +39,21 @@ export default function SidePanel() {
       {/* Right Panel — Login Form */}
       <div style={{ flex: 1, display: 'flex', alignItems: 'center', justifyContent: 'center', padding: 48 }}>
         <form onSubmit={handleLogin} style={{ width: '100%', maxWidth: 360, display: 'flex', flexDirection: 'column', gap: 20 }}>
-          <h2 style={{ fontSize: 22, fontWeight: 600, marginBottom: 4 }}>Welcome back</h2>
-          <p style={{ color: 'var(--dg-text-muted)', fontSize: 14, marginBottom: 8 }}>Sign in to access your dashboard</p>
+          <h2 style={{ fontSize: 22, fontWeight: 600, marginBottom: 4 }}>欢迎回来</h2>
+          <p style={{ color: 'var(--dg-text-muted)', fontSize: 14, marginBottom: 8 }}>登录以访问控制台</p>
 
           {error && <div style={{ color: '#f87171', fontSize: 13 }}>{error}</div>}
 
           <input
             type="text"
-            placeholder="Username"
+            placeholder="用户名"
             value={username}
             onChange={(e) => setUsername(e.target.value)}
             style={{ padding: '10px 14px', borderRadius: 8, background: 'var(--dg-bg-tertiary)', border: '1px solid var(--dg-border)', color: 'var(--dg-text-primary)', fontSize: 14, outline: 'none' }}
           />
           <input
             type="password"
-            placeholder="Password"
+            placeholder="密码"
             value={password}
             onChange={(e) => setPassword(e.target.value)}
             style={{ padding: '10px 14px', borderRadius: 8, background: 'var(--dg-bg-tertiary)', border: '1px solid var(--dg-border)', color: 'var(--dg-text-primary)', fontSize: 14, outline: 'none' }}
@@ -65,7 +65,7 @@ export default function SidePanel() {
             className="dg-gradient-bg"
             style={{ padding: '10px 14px', borderRadius: 8, border: 'none', color: '#fff', fontWeight: 600, fontSize: 14, cursor: loading || !username || !password ? 'not-allowed' : 'pointer', opacity: loading || !username || !password ? 0.6 : 1 }}
           >
-            {loading ? 'Signing in…' : 'Sign in'}
+            {loading ? '登录中…' : '登录'}
           </button>
         </form>
       </div>
diff --git a/frontend/src/components/login/SplitView.tsx b/frontend/src/components/login/SplitView.tsx
index 490a001..276c4e9 100644
--- a/frontend/src/components/login/SplitView.tsx
+++ b/frontend/src/components/login/SplitView.tsx
@@ -3,12 +3,12 @@ import { useTheme } from '@/hooks/useTheme';
 import { Sun, Moon, Database, Code, GitBranch, Bell, History, UserCog } from 'lucide-react';
 
 const features = [
-  { icon: Database, label: 'SQL Auditing', desc: 'Real-time query analysis' },
-  { icon: Code, label: 'Smart Rules', desc: 'Custom compliance rules' },
-  { icon: GitBranch, label: 'Version Control', desc: 'Track schema changes' },
-  { icon: Bell, label: 'Alerts', desc: 'Instant notifications' },
-  { icon: History, label: 'History', desc: 'Full audit trail' },
-  { icon: UserCog, label: 'Access Control', desc: 'Role-based permissions' },
+  { icon: Database, label: 'SQL审核', desc: '实时查询分析与合规检测' },
+  { icon: Code, label: '智能规则', desc: '自定义审核规则引擎' },
+  { icon: GitBranch, label: '变更管理', desc: 'DDL/DML 变更审批流' },
+  { icon: Bell, label: '即时通知', desc: '多渠道消息推送' },
+  { icon: History, label: '审计追踪', desc: '完整操作历史记录' },
+  { icon: UserCog, label: '权限管理', desc: '基于角色的访问控制' },
 ];
 
 export default function SplitView() {
@@ -28,10 +28,10 @@ export default function SplitView() {
       <div style={{ flex: 1, display: 'flex', flexDirection: 'column', justifyContent: 'center', padding: '48px 40px', background: 'var(--dg-bg-secondary)' }}>
         <div style={{ maxWidth: 440 }}>
           <h1 style={{ fontSize: 28, fontWeight: 700, marginBottom: 8 }}>
-            <span className="dg-gradient-text">SQL Audit Platform</span>
+            <span className="dg-gradient-text">SQL审核平台</span>
           </h1>
           <p style={{ color: 'var(--dg-text-muted)', fontSize: 15, marginBottom: 36, lineHeight: 1.5 }}>
-            Enterprise-grade SQL auditing and compliance management.
+            企业级 SQL 审核与合规管理平台。
           </p>
           <div style={{ display: 'grid', gridTemplateColumns: '1fr 1fr', gap: 16 }}>
             {features.map((f) => (
@@ -51,21 +51,21 @@ export default function SplitView() {
           onSubmit={handleLogin}
           style={{ width: '100%', maxWidth: 360, display: 'flex', flexDirection: 'column', gap: 20 }}
         >
-          <h2 style={{ fontSize: 22, fontWeight: 600, marginBottom: 4 }}>Sign in</h2>
-          <p style={{ color: 'var(--dg-text-muted)', fontSize: 14, marginBottom: 8 }}>Enter your credentials to continue</p>
+          <h2 style={{ fontSize: 22, fontWeight: 600, marginBottom: 4 }}>登录</h2>
+          <p style={{ color: 'var(--dg-text-muted)', fontSize: 14, marginBottom: 8 }}>请输入您的账号信息</p>
 
           {error && <div style={{ color: '#f87171', fontSize: 13 }}>{error}</div>}
 
           <input
             type="text"
-            placeholder="Username"
+            placeholder="用户名"
             value={username}
             onChange={(e) => setUsername(e.target.value)}
             style={{ padding: '10px 14px', borderRadius: 8, background: 'var(--dg-bg-tertiary)', border: '1px solid var(--dg-border)', color: 'var(--dg-text-primary)', fontSize: 14, outline: 'none' }}
           />
           <input
             type="password"
-            placeholder="Password"
+            placeholder="密码"
             value={password}
             onChange={(e) => setPassword(e.target.value)}
             style={{ padding: '10px 14px', borderRadius: 8, background: 'var(--dg-bg-tertiary)', border: '1px solid var(--dg-border)', color: 'var(--dg-text-primary)', fontSize: 14, outline: 'none' }}
@@ -77,7 +77,7 @@ export default function SplitView() {
             className="dg-gradient-bg"
             style={{ padding: '10px 14px', borderRadius: 8, border: 'none', color: '#fff', fontWeight: 600, fontSize: 14, cursor: loading || !username || !password ? 'not-allowed' : 'pointer', opacity: loading || !username || !password ? 0.6 : 1 }}
           >
-            {loading ? 'Signing in…' : 'Sign in'}
+            {loading ? '登录中…' : '登录'}
           </button>
         </form>
       </div>