diff --git a/internal/git/client.go b/internal/git/client.go
index cc00c8a..43eff48 100644
--- a/internal/git/client.go
+++ b/internal/git/client.go
@@ -1,20 +1,43 @@
 package git
 
 import (
+	"fmt"
 	"os"
 	"os/exec"
+	"regexp"
+	"strconv"
 	"strings"
 
 	tea "github.com/charmbracelet/bubbletea"
 )
 
+func GetCurrentBranch() string {
+	out, err := exec.Command("git", "rev-parse", "--abbrev-ref", "HEAD").Output()
+	if err != nil {
+		return "HEAD"
+	}
+	return strings.TrimSpace(string(out))
+}
+
+func GetRepoName() string {
+	out, err := exec.Command("git", "rev-parse", "--show-toplevel").Output()
+	if err != nil {
+		return "Repo"
+	}
+	path := strings.TrimSpace(string(out))
+	parts := strings.Split(path, "/")
+	if len(parts) > 0 {
+		return parts[len(parts)-1]
+	}
+	return "Repo"
+}
+
 func ListChangedFiles(targetBranch string) ([]string, error) {
 	cmd := exec.Command("git", "diff", "--name-only", targetBranch)
 	out, err := cmd.Output()
 	if err != nil {
 		return nil, err
 	}
-
 	files := strings.Split(strings.TrimSpace(string(out)), "\n")
 	if len(files) == 1 && files[0] == "" {
 		return []string{}, nil
@@ -32,17 +55,66 @@ func DiffCmd(targetBranch, path string) tea.Cmd {
 	}
 }
 
-func OpenEditorCmd(path string) tea.Cmd {
+func OpenEditorCmd(path string, lineNumber int) tea.Cmd {
 	editor := os.Getenv("EDITOR")
 	if editor == "" {
-		editor = "vim"
+		if _, err := exec.LookPath("nvim"); err == nil {
+			editor = "nvim"
+		} else {
+			editor = "vim"
+		}
 	}
-	c := exec.Command(editor, path)
+
+	var args []string
+	if lineNumber > 0 {
+		args = append(args, fmt.Sprintf("+%d", lineNumber))
+	}
+	args = append(args, path)
+
+	c := exec.Command(editor, args...)
 	c.Stdin, c.Stdout, c.Stderr = os.Stdin, os.Stdout, os.Stderr
 	return tea.ExecProcess(c, func(err error) tea.Msg {
 		return EditorFinishedMsg{Err: err}
 	})
 }
 
+func CalculateFileLine(diffContent string, visualLineIndex int) int {
+	lines := strings.Split(diffContent, "\n")
+	if visualLineIndex >= len(lines) {
+		return 0
+	}
+
+	re := regexp.MustCompile(`^.*?@@ \-\d+(?:,\d+)? \+(\d+)(?:,\d+)? @@`)
+
+	currentLineNo := 0
+
+	for i := 0; i <= visualLineIndex; i++ {
+		line := lines[i]
+
+		matches := re.FindStringSubmatch(line)
+		if len(matches) > 1 {
+			startLine, _ := strconv.Atoi(matches[1])
+			currentLineNo = startLine
+			continue
+		}
+
+		cleanLine := stripAnsi(line)
+		if strings.HasPrefix(cleanLine, " ") || strings.HasPrefix(cleanLine, "+") {
+			currentLineNo++
+		}
+	}
+
+	if currentLineNo == 0 {
+		return 1
+	}
+	return currentLineNo - 1
+}
+
+func stripAnsi(str string) string {
+	const ansi = "[\u001B\u009B][[\\]()#;?]*(?:(?:(?:[a-zA-Z\\d]*(?:;[a-zA-Z\\d]*)*)?\u0007)|(?:(?:\\d{1,4}(?:;\\d{0,4})*)?[\\dA-PRZcf-ntqry=><~]))"
+	var re = regexp.MustCompile(ansi)
+	return re.ReplaceAllString(str, "")
+}
+
 type DiffMsg struct{ Content string }
 type EditorFinishedMsg struct{ Err error }
diff --git a/internal/ui/model.go b/internal/ui/model.go
index 61fd093..1fc05e1 100644
--- a/internal/ui/model.go
+++ b/internal/ui/model.go
@@ -3,6 +3,7 @@ package ui
 import (
 	"fmt"
 	"io"
+	"strings"
 
 	"github.com/charmbracelet/bubbles/list"
 	"github.com/charmbracelet/bubbles/viewport"
@@ -15,10 +16,31 @@ import (
 
 const TargetBranch = "main"
 
+type Focus int
+
+const (
+	FocusTree Focus = iota
+	FocusDiff
+)
+
 type Model struct {
-	fileTree      list.Model
-	diffViewport  viewport.Model
+	fileTree     list.Model
+	diffViewport viewport.Model
+
+	// Data
 	selectedPath  string
+	currentBranch string
+	repoName      string
+
+	// Diff State
+	diffContent string
+	diffLines   []string
+	diffCursor  int
+
+	// UI State
+	focus    Focus
+	showHelp bool
+
 	width, height int
 }
 
@@ -31,10 +53,15 @@ func NewModel() Model {
 	l.SetShowHelp(false)
 	l.SetShowStatusBar(false)
 	l.SetFilteringEnabled(false)
+	l.DisableQuitKeybindings()
 
 	m := Model{
-		fileTree:     l,
-		diffViewport: viewport.New(0, 0),
+		fileTree:      l,
+		diffViewport:  viewport.New(0, 0),
+		focus:         FocusTree,
+		currentBranch: git.GetCurrentBranch(),
+		repoName:      git.GetRepoName(),
+		showHelp:      false,
 	}
 
 	if len(items) > 0 {
@@ -60,58 +87,213 @@ func (m Model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 	case tea.WindowSizeMsg:
 		m.width = msg.Width
 		m.height = msg.Height
-		treeWidth := int(float64(m.width) * 0.25)
-		m.fileTree.SetSize(treeWidth, m.height)
-		m.diffViewport.Width = m.width - treeWidth - 2
-		m.diffViewport.Height = m.height
+		m.updateSizes()
 
 	case tea.KeyMsg:
-		switch msg.String() {
-		case "q", "ctrl+c":
-			return m, tea.Quit
-		case "up", "k", "down", "j":
-			m.fileTree, cmd = m.fileTree.Update(msg)
-			cmds = append(cmds, cmd)
-			if item, ok := m.fileTree.SelectedItem().(tree.TreeItem); ok && !item.IsDir {
-				if item.FullPath != m.selectedPath {
-					m.selectedPath = item.FullPath
-					cmds = append(cmds, git.DiffCmd(TargetBranch, m.selectedPath))
-				}
-			}
-		case "e":
-			if m.selectedPath != "" {
-				return m, git.OpenEditorCmd(m.selectedPath)
-			}
+		// Toggle Help
+		if msg.String() == "?" {
+			m.showHelp = !m.showHelp
+			m.updateSizes()
+			return m, nil
 		}
 
+		// Quit
+		if msg.String() == "q" || msg.String() == "ctrl+c" {
+			return m, tea.Quit
+		}
+
+		// Navigation
+		switch msg.String() {
+		case "tab":
+			if m.focus == FocusTree {
+				m.focus = FocusDiff
+			} else {
+				m.focus = FocusTree
+			}
+
+		case "l", "]", "ctrl+l", "right":
+			m.focus = FocusDiff
+
+		case "h", "[", "ctrl+h", "left":
+			m.focus = FocusTree
+
+		// Editing
+		case "e", "enter":
+			if m.selectedPath != "" {
+				line := 0
+				if m.focus == FocusDiff {
+					line = git.CalculateFileLine(m.diffContent, m.diffCursor)
+				} else {
+					line = git.CalculateFileLine(m.diffContent, 0)
+				}
+				return m, git.OpenEditorCmd(m.selectedPath, line)
+			}
+
+		// Diff Cursor
+		case "j", "down":
+			if m.focus == FocusDiff {
+				if m.diffCursor < len(m.diffLines)-1 {
+					m.diffCursor++
+					if m.diffCursor >= m.diffViewport.YOffset+m.diffViewport.Height {
+						m.diffViewport.LineDown(1)
+					}
+				}
+			}
+		case "k", "up":
+			if m.focus == FocusDiff {
+				if m.diffCursor > 0 {
+					m.diffCursor--
+					if m.diffCursor < m.diffViewport.YOffset {
+						m.diffViewport.LineUp(1)
+					}
+				}
+			}
+		}
+	}
+
+	// Update Components
+	if m.focus == FocusTree {
+		m.fileTree, cmd = m.fileTree.Update(msg)
+		cmds = append(cmds, cmd)
+
+		if item, ok := m.fileTree.SelectedItem().(tree.TreeItem); ok && !item.IsDir {
+			if item.FullPath != m.selectedPath {
+				m.selectedPath = item.FullPath
+				m.diffCursor = 0
+				m.diffViewport.GotoTop()
+				cmds = append(cmds, git.DiffCmd(TargetBranch, m.selectedPath))
+			}
+		}
+	}
+
+	switch msg := msg.(type) {
 	case git.DiffMsg:
+		m.diffContent = msg.Content
+		m.diffLines = strings.Split(msg.Content, "\n")
 		m.diffViewport.SetContent(msg.Content)
 
 	case git.EditorFinishedMsg:
-		if msg.Err != nil {
-		}
 		return m, git.DiffCmd(TargetBranch, m.selectedPath)
 	}
 
 	return m, tea.Batch(cmds...)
 }
 
+func (m *Model) updateSizes() {
+	reservedHeight := 1
+	if m.showHelp {
+		reservedHeight += 6
+	}
+
+	contentHeight := m.height - reservedHeight
+	if contentHeight < 1 {
+		contentHeight = 1
+	}
+
+	treeWidth := int(float64(m.width) * 0.20)
+	if treeWidth < 20 {
+		treeWidth = 20
+	}
+
+	m.fileTree.SetSize(treeWidth, contentHeight)
+	m.diffViewport.Width = m.width - treeWidth - 2
+	m.diffViewport.Height = contentHeight
+}
+
 func (m Model) View() string {
 	if m.width == 0 {
 		return "Loading..."
 	}
 
-	treeView := PaneStyle.Copy().
+	treeStyle := PaneStyle
+	if m.focus == FocusTree {
+		treeStyle = FocusedPaneStyle
+	} else {
+		treeStyle = PaneStyle
+	}
+
+	treeView := treeStyle.Copy().
 		Width(m.fileTree.Width()).
 		Height(m.fileTree.Height()).
 		Render(m.fileTree.View())
 
+	var renderedDiff strings.Builder
+	start := m.diffViewport.YOffset
+	end := start + m.diffViewport.Height
+	if end > len(m.diffLines) {
+		end = len(m.diffLines)
+	}
+
+	for i := start; i < end; i++ {
+		line := m.diffLines[i]
+		if m.focus == FocusDiff && i == m.diffCursor {
+			line = SelectedItemStyle.Render(line)
+		} else {
+			line = "  " + line
+		}
+		renderedDiff.WriteString(line + "\n")
+	}
+
 	diffView := DiffStyle.Copy().
 		Width(m.diffViewport.Width).
 		Height(m.diffViewport.Height).
-		Render(m.diffViewport.View())
+		Render(renderedDiff.String())
 
-	return lipgloss.JoinHorizontal(lipgloss.Top, treeView, diffView)
+	mainPanes := lipgloss.JoinHorizontal(lipgloss.Top, treeView, diffView)
+
+	// Status Bar
+	repoSection := StatusKeyStyle.Render(" " + m.repoName)
+	divider := StatusDividerStyle.Render("│")
+	branchSection := StatusBarStyle.Render(fmt.Sprintf(" %s ↔ %s", m.currentBranch, TargetBranch))
+
+	leftStatus := lipgloss.JoinHorizontal(lipgloss.Center, repoSection, divider, branchSection)
+	rightStatus := StatusBarStyle.Render("? Help")
+
+	statusBar := StatusBarStyle.Copy().
+		Width(m.width).
+		Render(lipgloss.JoinHorizontal(lipgloss.Top,
+			leftStatus,
+			lipgloss.PlaceHorizontal(m.width-lipgloss.Width(leftStatus)-lipgloss.Width(rightStatus), lipgloss.Right, rightStatus),
+		))
+
+	// Help Drawer
+	var finalView string
+	if m.showHelp {
+		col1 := lipgloss.JoinVertical(lipgloss.Left,
+			HelpTextStyle.Render("↑/k   Move Up"),
+			HelpTextStyle.Render("↓/j   Move Down"),
+		)
+		col2 := lipgloss.JoinVertical(lipgloss.Left,
+			HelpTextStyle.Render("←/h   Left Panel"),
+			HelpTextStyle.Render("→/l   Right Panel"),
+		)
+		col3 := lipgloss.JoinVertical(lipgloss.Left,
+			HelpTextStyle.Render("Tab   Switch Panel"),
+			HelpTextStyle.Render("Ent/e Edit File"),
+		)
+		col4 := lipgloss.JoinVertical(lipgloss.Left,
+			HelpTextStyle.Render("q     Quit"),
+			HelpTextStyle.Render("?     Close Help"),
+		)
+
+		helpDrawer := HelpDrawerStyle.Copy().
+			Width(m.width).
+			Render(lipgloss.JoinHorizontal(lipgloss.Top,
+				col1,
+				lipgloss.NewStyle().Width(4).Render(""),
+				col2,
+				lipgloss.NewStyle().Width(4).Render(""),
+				col3,
+				lipgloss.NewStyle().Width(4).Render(""),
+				col4,
+			))
+
+		finalView = lipgloss.JoinVertical(lipgloss.Top, mainPanes, helpDrawer, statusBar)
+	} else {
+		finalView = lipgloss.JoinVertical(lipgloss.Top, mainPanes, statusBar)
+	}
+
+	return finalView
 }
 
 type listDelegate struct{}
@@ -124,10 +306,9 @@ func (d listDelegate) Render(w io.Writer, m list.Model, index int, item list.Ite
 	if !ok {
 		return
 	}
-
 	str := i.Title()
 	if index == m.Index() {
-		fmt.Fprint(w, SelectedItemStyle.Render("│ "+str))
+		fmt.Fprint(w, SelectedItemStyle.Render(str))
 	} else {
 		fmt.Fprint(w, ItemStyle.Render(str))
 	}
diff --git a/internal/ui/styles.go b/internal/ui/styles.go
index fb5faf6..8238505 100644
--- a/internal/ui/styles.go
+++ b/internal/ui/styles.go
@@ -3,23 +3,61 @@ package ui
 import "github.com/charmbracelet/lipgloss"
 
 var (
+	// -- THEME: Neutral & Clean --
 	ColorBorder   = lipgloss.AdaptiveColor{Light: "#D9DCCF", Dark: "#383838"}
-	ColorSelected = lipgloss.AdaptiveColor{Light: "#1F1F1F", Dark: "#F8F8F2"}
-	ColorInactive = lipgloss.AdaptiveColor{Light: "#A8A8A8", Dark: "#626262"}
-	ColorAccent   = lipgloss.AdaptiveColor{Light: "#00BCF0", Dark: "#00BCF0"} // Cyan
+	ColorFocus    = lipgloss.AdaptiveColor{Light: "#000000", Dark: "#E5E5E5"}
+	ColorText     = lipgloss.AdaptiveColor{Light: "#1F1F1F", Dark: "#F8F8F2"}
+	ColorSubtle   = lipgloss.AdaptiveColor{Light: "#A8A8A8", Dark: "#626262"}
+	ColorCursorBg = lipgloss.AdaptiveColor{Light: "#E5E5E5", Dark: "#3E3E3E"}
 
+	// -- Status Bar Colors --
+	ColorBarBg = lipgloss.AdaptiveColor{Light: "#F2F2F2", Dark: "#1F1F1F"}
+	ColorBarFg = lipgloss.AdaptiveColor{Light: "#6E6E6E", Dark: "#9E9E9E"}
+
+	// -- PANE STYLES --
 	PaneStyle = lipgloss.NewStyle().
 			Border(lipgloss.NormalBorder(), false, true, false, false).
-			BorderForeground(ColorBorder).
-			MarginRight(1)
+			BorderForeground(ColorBorder)
 
-	DiffStyle = lipgloss.NewStyle().
-			Padding(0, 1)
+	FocusedPaneStyle = PaneStyle.Copy().
+				BorderForeground(ColorFocus)
 
-	ItemStyle = lipgloss.NewStyle().PaddingLeft(1)
+	DiffStyle = lipgloss.NewStyle().Padding(0, 0)
+	ItemStyle = lipgloss.NewStyle().PaddingLeft(2)
 
 	SelectedItemStyle = lipgloss.NewStyle().
-				PaddingLeft(0).
-				Foreground(ColorSelected).
-				Bold(true)
+				PaddingLeft(1).
+				Background(ColorCursorBg).
+				Foreground(ColorText).
+				Bold(true).
+				Width(1000)
+
+	// -- STATUS BAR STYLES --
+	StatusBarStyle = lipgloss.NewStyle().
+			Foreground(ColorBarFg).
+			Background(ColorBarBg).
+			Padding(0, 1)
+
+	StatusKeyStyle = lipgloss.NewStyle().
+			Foreground(ColorText).
+			Background(ColorBarBg).
+			Bold(true).
+			Padding(0, 1)
+
+	StatusDividerStyle = lipgloss.NewStyle().
+				Foreground(ColorSubtle).
+				Background(ColorBarBg).
+				Padding(0, 0)
+
+	// -- NEW HELP STYLES (Transparent & Subtle) --
+	// No background, subtle color, no bold
+	HelpTextStyle = lipgloss.NewStyle().
+			Foreground(ColorSubtle).
+			Padding(0, 1)
+
+	HelpDrawerStyle = lipgloss.NewStyle().
+		// No Background() definition means transparent
+		Border(lipgloss.NormalBorder(), true, false, false, false). // Top border only
+		BorderForeground(ColorBorder).
+		Padding(1, 2)
 )