From 0b1db4e47e71cf977016e7afe9da2d5087756117 Mon Sep 17 00:00:00 2001
From: deveshctl <deveshpharswanhk@gmail.com>
Date: Wed, 5 Aug 2026 15:11:30 +0530
Subject: [PATCH 1/3] perf(tui): precompute session-scoped style set to
 eliminate per-frame allocations
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

The theme is fixed at startup and never changes, yet every frame built
~300-400 fresh lipgloss.Style structs via styleWithFg / lipgloss.NewStyle()
calls scattered across the hot render paths.

Added a themeStyles struct (tui/styles.go) with 26 pre-built Style fields,
populated once in NewModel via newThemeStyles(theme) and stored as m.styles.
Threaded through internal structs (treePaneInput, splitTreeInput,
viewerParams) so the hot per-row renderers read a field instead of
allocating.

Replaced all static styleWithFg / lipgloss.NewStyle() calls in:
- tui/model.go   — renderHeader, renderStatusBar, renderViewerStatusBar,
                   viewLoading, viewError, separator line
- tui/filetree.go — renderTreeHeader, renderFilterBar, renderSplitDivider,
                   formatFileNodeLine, renderNameWithHighlight
- tui/layers.go  — renderCommandBar, highlightInstruction, formatLayerLine,
                   renderSizeColumn
- tui/fileview.go — renderViewerLine, renderViewerSearchBar, overlayCursor,
                   gutter, truncation/binary/empty notices

Dynamic styles (per-row diff color, delta color, selected-row bg,
search-current highlight) remain inline as their color varies per call.

Updated all test call sites to pass themeStyles{} (zero value is correct
for structural tests that check content not color).
---
 CHANGELOG.md         |  5 +++
 tui/filetree.go      | 76 +++++++++++++++++++-----------------
 tui/filetree_test.go | 10 ++---
 tui/fileview.go      | 51 ++++++++++++------------
 tui/layers.go        | 38 +++++++++---------
 tui/layers_test.go   | 16 ++++----
 tui/model.go         | 92 +++++++++++++++++++++----------------------
 tui/model_test.go    | 10 ++---
 tui/styles.go        | 93 ++++++++++++++++++++++++++++++++++++++++++++
 9 files changed, 246 insertions(+), 145 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index e1bea27..fb12da4 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -33,6 +33,11 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
   per candidate position when scanning each visible line for matches. The inner
   scan now uses `strings.Index` on the lowercased line tail, reducing allocation
   pressure during active search through large files.
+- All theme-derived lipgloss styles are now built once at startup into a
+  session-scoped style set and reused every frame. The theme is fixed for the
+  session, so the ~300–400 per-frame style allocations that were rebuilding
+  identical structs on every redraw are eliminated. Reduces GC pressure
+  noticeably on low-power machines and slow terminals.
 
 ## [v1.6.0] - 2026-07-28
 
diff --git a/tui/filetree.go b/tui/filetree.go
index 9a22732..d124586 100644
--- a/tui/filetree.go
+++ b/tui/filetree.go
@@ -12,11 +12,12 @@ import (
 	"github.com/deveshctl/layerx/image"
 )
 
-func renderFileTree(t Theme, files []*image.FileNode, cursor, offset int, width, height int, focused bool, filterActive bool, filterQuery string, treeMode bool, aggregated bool, collapsed map[string]bool, currentLayer int) string {
+func renderFileTree(t Theme, st themeStyles, files []*image.FileNode, cursor, offset int, width, height int, focused bool, filterActive bool, filterQuery string, treeMode bool, aggregated bool, collapsed map[string]bool, currentLayer int) string {
 	contentWidth := width - 2
 
 	body, hasAbove, hasBelow := renderTreeBody(treePaneInput{
 		theme:        t,
+		styles:       st,
 		files:        files,
 		cursor:       cursor,
 		offset:       offset,
@@ -46,6 +47,7 @@ func renderFileTree(t Theme, files []*image.FileNode, cursor, offset int, width,
 
 type treePaneInput struct {
 	theme         Theme
+	styles        themeStyles
 	files         []*image.FileNode
 	cursor        int
 	offset        int
@@ -83,7 +85,7 @@ func renderTreeBody(in treePaneInput) (body string, hasAbove, hasBelow bool) {
 	var sb strings.Builder
 
 	if in.showHeader {
-		sb.WriteString(renderTreeHeader(in.theme, in.contentWidth))
+		sb.WriteString(renderTreeHeader(in.styles, in.contentWidth))
 		sb.WriteString("\n")
 		sb.WriteString(renderDivider(in.theme, in.contentWidth))
 		sb.WriteString("\n")
@@ -108,8 +110,8 @@ func renderTreeBody(in treePaneInput) (body string, hasAbove, hasBelow bool) {
 		midpoint := contentHeight / 2
 		for i := 0; i < contentHeight; i++ {
 			if i == midpoint {
-				sb.WriteString(pad)
-				sb.WriteString(styleWithFg(in.theme.Unchanged).Render(msg))
+			sb.WriteString(pad)
+				sb.WriteString(in.styles.unchanged.Render(msg))
 			}
 			if i < contentHeight-1 {
 				sb.WriteString("\n")
@@ -123,7 +125,7 @@ func renderTreeBody(in treePaneInput) (body string, hasAbove, hasBelow bool) {
 		visible := in.files[in.offset:end]
 
 		for i, f := range visible {
-			line := formatFileNodeLine(in.theme, f, in.offset+i == in.cursor, in.contentWidth, in.treeMode, in.collapsed, in.currentLayer, in.filterQuery)
+			line := formatFileNodeLine(in.theme, in.styles, f, in.offset+i == in.cursor, in.contentWidth, in.treeMode, in.collapsed, in.currentLayer, in.filterQuery)
 			sb.WriteString(line)
 			if i < len(visible)-1 {
 				sb.WriteString("\n")
@@ -138,7 +140,7 @@ func renderTreeBody(in treePaneInput) (body string, hasAbove, hasBelow bool) {
 
 	if in.showFilterBar {
 		sb.WriteString("\n")
-		sb.WriteString(renderFilterBar(in.theme, in.filterActive, in.filterQuery, len(in.files), in.contentWidth))
+		sb.WriteString(renderFilterBar(in.styles, in.filterActive, in.filterQuery, len(in.files), in.contentWidth))
 	}
 
 	hasAbove = in.offset > 0
@@ -155,6 +157,7 @@ func renderTreeBody(in treePaneInput) (body string, hasAbove, hasBelow bool) {
 
 type splitTreeInput struct {
 	theme         Theme
+	styles        themeStyles
 	width, height int
 	currentLayer  int
 	treeMode      bool
@@ -203,6 +206,7 @@ func renderSplitFileTree(in splitTreeInput) string {
 
 	topBody, topAbove, topBelow := renderTreeBody(treePaneInput{
 		theme:         in.theme,
+		styles:        in.styles,
 		files:         in.topFiles,
 		cursor:        in.topCursor,
 		offset:        in.topOffset,
@@ -235,7 +239,7 @@ func renderSplitFileTree(in splitTreeInput) string {
 		emptyMsg:      "(no entries at this layer)",
 	})
 
-	divider := renderSplitDivider(in.theme, in.botFocused, contentWidth, in.botFiles, in.botCursor)
+	divider := renderSplitDivider(in.styles, in.botFocused, contentWidth, in.botFiles, in.botCursor)
 
 	body := topBody + "\n" + divider + "\n" + botBody
 
@@ -252,7 +256,7 @@ func renderSplitFileTree(in splitTreeInput) string {
 // match-count and a focus-weight background when that pane has focus.
 // This places the "▾ Cumulative" affordance on a row that would otherwise
 // be wasted whitespace.
-func renderSplitDivider(t Theme, botFocused bool, contentWidth int, botFiles []*image.FileNode, botCursor int) string {
+func renderSplitDivider(st themeStyles, botFocused bool, contentWidth int, botFiles []*image.FileNode, botCursor int) string {
 	label := " ▾ Cumulative "
 	if botFocused && len(botFiles) > 0 {
 		label = fmt.Sprintf(" ▾ Cumulative %d/%d ", botCursor+1, len(botFiles))
@@ -260,11 +264,13 @@ func renderSplitDivider(t Theme, botFocused bool, contentWidth int, botFiles []*
 		label = fmt.Sprintf(" ▾ Cumulative · %d items ", len(botFiles))
 	}
 
-	labelStyle := lipgloss.NewStyle().Foreground(t.Unchanged)
-	lineStyle := lipgloss.NewStyle().Foreground(t.Separator)
+	var labelStyle, lineStyle lipgloss.Style
 	if botFocused {
-		labelStyle = lipgloss.NewStyle().Foreground(t.Accent).Bold(true)
-		lineStyle = lipgloss.NewStyle().Foreground(t.Accent)
+		labelStyle = st.accent.Bold(true)
+		lineStyle = st.accent
+	} else {
+		labelStyle = st.unchanged
+		lineStyle = st.separator
 	}
 
 	rendered := labelStyle.Render(label)
@@ -299,7 +305,7 @@ func buildSplitTitle(in splitTreeInput) string {
 	return topPart + "  ·  " + botPart
 }
 
-func renderTreeHeader(t Theme, maxWidth int) string {
+func renderTreeHeader(st themeStyles, maxWidth int) string {
 	const permCol = 10
 	const uidGidCol = 8
 	const sizeCol = 8
@@ -328,19 +334,19 @@ func renderTreeHeader(t Theme, maxWidth int) string {
 	if lipgloss.Width(header) > maxWidth {
 		header = ansi.Truncate(header, maxWidth, "")
 	}
-	return styleWithFg(t.MetaDim).Render(header)
+	return st.metaDim.Render(header)
 }
 
-func renderFilterBar(t Theme, active bool, query string, matchCount int, maxWidth int) string {
+func renderFilterBar(st themeStyles, active bool, query string, matchCount int, maxWidth int) string {
 	if active {
-		prefix := styleWithFg(t.Accent).Render("/ ")
+		prefix := st.accent.Render("/ ")
 		cursor := query + "█"
 		return prefix + cursor
 	}
-	prefix := styleWithFg(t.Accent).Render("/ ")
-	queryStr := styleWithFg(t.Selected).Render(query)
-	matches := styleWithFg(t.StatusDim).Render(fmt.Sprintf("  (%d matches)", matchCount))
-	hint := styleWithFg(t.Unchanged).Render("  [⌫ clear]")
+	prefix := st.accent.Render("/ ")
+	queryStr := st.selected.Render(query)
+	matches := st.statusDimRaw.Render(fmt.Sprintf("  (%d matches)", matchCount))
+	hint := st.unchanged.Render("  [⌫ clear]")
 
 	line := prefix + queryStr + matches + hint
 	lineWidth := lipgloss.Width(line)
@@ -350,7 +356,7 @@ func renderFilterBar(t Theme, active bool, query string, matchCount int, maxWidt
 	return line
 }
 
-func formatFileNodeLine(t Theme, f *image.FileNode, selected bool, maxWidth int, treeMode bool, collapsed map[string]bool, currentLayer int, filterQuery string) string {
+func formatFileNodeLine(t Theme, st themeStyles, f *image.FileNode, selected bool, maxWidth int, treeMode bool, collapsed map[string]bool, currentLayer int, filterQuery string) string {
 	perms := image.FormatMode(f.Mode)
 	uidGid := fmt.Sprintf("%d:%d", f.UID, f.GID)
 	flat := !treeMode
@@ -428,11 +434,11 @@ func formatFileNodeLine(t Theme, f *image.FileNode, selected bool, maxWidth int,
 	var diffGlyph string
 	switch f.DiffType {
 	case image.Added:
-		diffGlyph = styleWithFg(t.Added).Render("+ ")
+		diffGlyph = st.added.Render("+ ")
 	case image.Modified:
-		diffGlyph = styleWithFg(t.Modified).Render("~ ")
+		diffGlyph = st.modified.Render("~ ")
 	case image.Removed:
-		diffGlyph = styleWithFg(t.Removed).Render("- ")
+		diffGlyph = st.removed.Render("- ")
 	default:
 		diffGlyph = "  "
 	}
@@ -460,18 +466,18 @@ func formatFileNodeLine(t Theme, f *image.FileNode, selected bool, maxWidth int,
 			metaCols = sizeStr + strings.Repeat(" ", colGap)
 		}
 		fullLine := selGlyph + metaCols + fullName + originSuffix + strings.Repeat(" ", namePad)
-		return lipgloss.NewStyle().Foreground(t.Selected).Background(t.SelectedBg).Render(fullLine)
+		return st.selectedTreeBg.Render(fullLine)
 	}
 
 	var metaCols string
 	if showPerms {
-		permStr := styleWithFg(t.MetaDim).Render(padRight(perms, permCol))
-		uidStr := styleWithFg(t.MetaDim).Render(padRight(uidGid, uidGidCol))
-		sizeStr := styleWithFg(t.HeaderDim).Render(padLeft(size, sizeCol))
+		permStr := st.metaDim.Render(padRight(perms, permCol))
+		uidStr := st.metaDim.Render(padRight(uidGid, uidGidCol))
+		sizeStr := st.headerDim.Render(padLeft(size, sizeCol))
 		gap := strings.Repeat(" ", colGap)
 		metaCols = permStr + gap + uidStr + gap + sizeStr + gap
 	} else if showSize {
-		sizeStr := styleWithFg(t.HeaderDim).Render(padLeft(size, sizeCol))
+		sizeStr := st.headerDim.Render(padLeft(size, sizeCol))
 		metaCols = sizeStr + strings.Repeat(" ", colGap)
 	}
 
@@ -480,21 +486,21 @@ func formatFileNodeLine(t Theme, f *image.FileNode, selected bool, maxWidth int,
 	fullNameRuneLen := len([]rune(fullName))
 
 	if flat || (wasTruncated && prefixRuneLen >= fullNameRuneLen) {
-		nameRendered = renderNameWithHighlight(t, fullName, filterQuery, diffColorForNode(t, f))
+		nameRendered = renderNameWithHighlight(st, fullName, filterQuery, diffColorForNode(t, f))
 	} else {
 		fullRunes := []rune(fullName)
 		var nameOnly string
 		if prefixRuneLen < len(fullRunes) {
 			nameOnly = string(fullRunes[prefixRuneLen:])
 		}
-		treePrefixRendered := styleWithFg(t.TreeDim).Render(treePrefix)
-		nameOnlyRendered := renderNameWithHighlight(t, nameOnly, filterQuery, diffColorForNode(t, f))
+		treePrefixRendered := st.treeDim.Render(treePrefix)
+		nameOnlyRendered := renderNameWithHighlight(st, nameOnly, filterQuery, diffColorForNode(t, f))
 		nameRendered = treePrefixRendered + nameOnlyRendered
 	}
 
 	var originRendered string
 	if showOrigin {
-		originRendered = styleWithFg(t.MetaDim).Render(originSuffix)
+		originRendered = st.metaDim.Render(originSuffix)
 	}
 
 	nameRenderedWidth := lipgloss.Width(nameRendered) + lipgloss.Width(originRendered)
@@ -627,7 +633,7 @@ func diffColorForNode(t Theme, f *image.FileNode) color.Color {
 	}
 }
 
-func renderNameWithHighlight(t Theme, name, query string, fg color.Color) string {
+func renderNameWithHighlight(st themeStyles, name, query string, fg color.Color) string {
 	if query == "" || name == "" {
 		return styleWithFg(fg).Render(name)
 	}
@@ -654,6 +660,6 @@ func renderNameWithHighlight(t Theme, name, query string, fg color.Color) string
 	after := string(runes[runeIdx+len(queryRunes):])
 
 	normal := styleWithFg(fg)
-	highlight := lipgloss.NewStyle().Foreground(fg).Background(t.SearchHighlightBg)
+	highlight := st.searchHighlight.Foreground(fg)
 	return normal.Render(before) + highlight.Render(match) + normal.Render(after)
 }
diff --git a/tui/filetree_test.go b/tui/filetree_test.go
index 530061f..317b7ec 100644
--- a/tui/filetree_test.go
+++ b/tui/filetree_test.go
@@ -27,7 +27,7 @@ func TestRenderFileTree_FilterActiveSuppressesBelowIndicator(t *testing.T) {
 	// (the bar persists until the query is cleared). The filter bar
 	// occupies the panel's last row, where renderPanel would otherwise
 	// paint the ▾ scroll indicator.
-	out := renderFileTree(CatppuccinMocha(), files, 0, 0, 60, 10, true, false, "f", false, false, nil, 0)
+	out := renderFileTree(CatppuccinMocha(), themeStyles{}, files, 0, 0, 60, 10, true, false, "f", false, false, nil, 0)
 	if strings.Contains(out, "▾") {
 		t.Fatalf("expected no ▾ when filter bar occupies last row; got panel:\n%s", out)
 	}
@@ -35,7 +35,7 @@ func TestRenderFileTree_FilterActiveSuppressesBelowIndicator(t *testing.T) {
 
 func TestRenderFileTree_NoFilterRetainsBelowIndicator(t *testing.T) {
 	files := fakeFiles(50)
-	out := renderFileTree(CatppuccinMocha(), files, 0, 0, 60, 10, true, false, "", false, false, nil, 0)
+	out := renderFileTree(CatppuccinMocha(), themeStyles{}, files, 0, 0, 60, 10, true, false, "", false, false, nil, 0)
 	if !strings.Contains(out, "▾") {
 		t.Fatalf("expected ▾ when overflow exists and filter is not active; got panel:\n%s", out)
 	}
@@ -43,7 +43,7 @@ func TestRenderFileTree_NoFilterRetainsBelowIndicator(t *testing.T) {
 
 func TestRenderFileTree_TitleSingleLayerMode(t *testing.T) {
 	files := fakeFiles(3)
-	out := renderFileTree(CatppuccinMocha(), files, 0, 0, 60, 10, true, false, "", false, false, nil, 0)
+	out := renderFileTree(CatppuccinMocha(), themeStyles{}, files, 0, 0, 60, 10, true, false, "", false, false, nil, 0)
 	if !strings.Contains(out, "Current Layer Contents") {
 		t.Fatalf("expected title to contain 'Current Layer Contents' when aggregated=false; got:\n%s", out)
 	}
@@ -54,7 +54,7 @@ func TestRenderFileTree_TitleSingleLayerMode(t *testing.T) {
 
 func TestRenderFileTree_TitleAggregatedMode(t *testing.T) {
 	files := fakeFiles(3)
-	out := renderFileTree(CatppuccinMocha(), files, 0, 0, 60, 10, true, false, "", false, true, nil, 0)
+	out := renderFileTree(CatppuccinMocha(), themeStyles{}, files, 0, 0, 60, 10, true, false, "", false, true, nil, 0)
 	if !strings.Contains(out, "Aggregated Layer Contents") {
 		t.Fatalf("expected title to contain 'Aggregated Layer Contents' when aggregated=true; got:\n%s", out)
 	}
@@ -107,7 +107,7 @@ func TestRenderSplitFileTree_DividerCarriesCumulativeLabel(t *testing.T) {
 // label — that title is reserved for the split layout.
 func TestRenderFileTree_SinglePaneOmitsSplitTitle(t *testing.T) {
 	files := fakeFiles(3)
-	out := renderFileTree(CatppuccinMocha(), files, 0, 0, 60, 10, true, false, "", false, false, nil, 0)
+	out := renderFileTree(CatppuccinMocha(), themeStyles{}, files, 0, 0, 60, 10, true, false, "", false, false, nil, 0)
 	if strings.Contains(out, "Layer Δ") {
 		t.Fatalf("single-pane file tree must not advertise the split title 'Layer Δ'; got:\n%s", out)
 	}
diff --git a/tui/fileview.go b/tui/fileview.go
index 3657275..6b3df83 100644
--- a/tui/fileview.go
+++ b/tui/fileview.go
@@ -36,6 +36,7 @@ type viewerParams struct {
 	// no search is active, it is used directly to skip per-frame chroma work.
 	highlightedLines []string
 	theme            Theme
+	styles           themeStyles
 }
 
 func renderFileView(p viewerParams) string {
@@ -66,7 +67,7 @@ func renderFileView(p viewerParams) string {
 		msg := fmt.Sprintf("Binary file (%s) — cannot display", image.FormatBytes(p.content.Size))
 		hint := "Press Esc to return"
 		body := lipgloss.Place(contentWidth, contentHeight, lipgloss.Center, lipgloss.Center,
-			styleWithFg(p.theme.Removed).Render(msg)+"\n\n"+styleWithFg(p.theme.StatusDim).Render(hint))
+			p.styles.removed.Render(msg)+"\n\n"+p.styles.statusDimRaw.Render(hint))
 		return renderPanel(p.theme, body, title, true, contentWidth, p.height, false, false)
 	}
 
@@ -74,7 +75,7 @@ func renderFileView(p viewerParams) string {
 		msg := "Empty file (0 bytes)"
 		hint := "Press Esc to return"
 		body := lipgloss.Place(contentWidth, contentHeight, lipgloss.Center, lipgloss.Center,
-			styleWithFg(p.theme.Unchanged).Render(msg)+"\n\n"+styleWithFg(p.theme.StatusDim).Render(hint))
+			p.styles.unchanged.Render(msg)+"\n\n"+p.styles.statusDimRaw.Render(hint))
 		return renderPanel(p.theme, body, title, true, contentWidth, p.height, false, false)
 	}
 
@@ -116,11 +117,11 @@ func renderFileView(p viewerParams) string {
 	for i, line := range visible {
 		lineNum := p.offset + i + 1
 		lineIdx := p.offset + i
-		gutter := styleWithFg(p.theme.MetaDim).Render(fmt.Sprintf("%*d ", gutterDigits, lineNum))
+		gutter := p.styles.metaDim.Render(fmt.Sprintf("%*d ", gutterDigits, lineNum))
 		gutterW := ansi.StringWidth(gutter)
 
 		maxLineWidth := max(contentWidth-gutterW, 1)
-		lineContent := renderViewerLine(p.theme, line, lineIdx, p.searchQuery, p.searchMatches, p.searchCursor, syntaxHighlight)
+		lineContent := renderViewerLine(p.styles, line, lineIdx, p.searchQuery, p.searchMatches, p.searchCursor, syntaxHighlight)
 
 		// Cursor sits on the first visible line. Overlay it before truncation
 		// so the cursor cell is preserved (or correctly clipped) by the same
@@ -128,7 +129,7 @@ func renderFileView(p viewerParams) string {
 		// positions still adjust hOffset in scrollViewLeft/Right, so by the
 		// time we render the cursor is always within the visible window.
 		if i == 0 {
-			lineContent = overlayCursor(p.theme, lineContent, p.cursorCol)
+			lineContent = overlayCursor(p.styles, lineContent, p.cursorCol)
 		}
 
 		// Horizontal scroll: keep the styled output intact, then trim from
@@ -162,13 +163,13 @@ func renderFileView(p viewerParams) string {
 
 	if showSearchBar {
 		sb.WriteString("\n")
-		sb.WriteString(renderViewerSearchBar(p.theme, p.searchQuery, p.searchActive, len(p.searchMatches), p.searchCursor, contentWidth))
+		sb.WriteString(renderViewerSearchBar(p, p.searchQuery, p.searchActive, len(p.searchMatches), p.searchCursor, contentWidth))
 	}
 
 	if p.content.Truncated {
 		notice := fmt.Sprintf("  File truncated at 1 MB (total: %s)", image.FormatBytes(p.content.Size))
 		sb.WriteString("\n")
-		sb.WriteString(styleWithFg(p.theme.Modified).Render(notice))
+		sb.WriteString(p.styles.modified.Render(notice))
 	}
 
 	hasAbove := p.offset > 0
@@ -183,11 +184,11 @@ func renderFileView(p viewerParams) string {
 // When the cursor is past the end of the rendered line (cursor on a short
 // line below a longer one), the line is padded with spaces so the block
 // still renders at the requested column rather than collapsing onto EOL.
-func overlayCursor(t Theme, line string, col int) string {
+func overlayCursor(st themeStyles, line string, col int) string {
 	if col < 0 {
 		return line
 	}
-	cursorStyle := lipgloss.NewStyle().Foreground(t.SearchCurrentFg).Background(t.Accent)
+	cursorStyle := st.cursorOverlay
 	w := ansi.StringWidth(line)
 	if col >= w {
 		pad := strings.Repeat(" ", col-w)
@@ -202,12 +203,12 @@ func overlayCursor(t Theme, line string, col int) string {
 	return pre + cursorStyle.Render(cell) + post
 }
 
-func renderViewerLine(t Theme, line string, lineIdx int, query string, matches [][2]int, matchCursor int, syntaxHighlight bool) string {
+func renderViewerLine(st themeStyles, line string, lineIdx int, query string, matches [][2]int, matchCursor int, syntaxHighlight bool) string {
 	if query == "" || len(matches) == 0 {
 		if syntaxHighlight {
 			return line
 		}
-		return styleWithFg(t.FileName).Render(line)
+		return st.fileName.Render(line)
 	}
 
 	lineRunes := []rune(line)
@@ -269,44 +270,44 @@ func renderViewerLine(t Theme, line string, lineIdx int, query string, matches [
 		segments = append(segments, segment{text: string(lineRunes[pos:])})
 	}
 	if len(segments) == 0 {
-		return styleWithFg(t.FileName).Render(line)
+		return st.fileName.Render(line)
 	}
 
 	var sb strings.Builder
 	for _, seg := range segments {
 		if seg.current {
-			sb.WriteString(lipgloss.NewStyle().Foreground(t.SearchCurrentFg).Background(t.SearchCurrentBg).Render(seg.text))
+			sb.WriteString(st.searchCurrentLine.Render(seg.text))
 		} else if seg.match {
-			sb.WriteString(lipgloss.NewStyle().Foreground(t.FileName).Background(t.SearchHighlightBg).Render(seg.text))
+			sb.WriteString(st.searchHighlightFile.Render(seg.text))
 		} else {
-			sb.WriteString(styleWithFg(t.FileName).Render(seg.text))
+			sb.WriteString(st.fileName.Render(seg.text))
 		}
 	}
 	return sb.String()
 }
 
-func renderViewerSearchBar(t Theme, query string, active bool, matchCount, cursor, maxWidth int) string {
-	prefix := styleWithFg(t.Accent).Render("/ ")
+func renderViewerSearchBar(p viewerParams, query string, active bool, matchCount, cursor, maxWidth int) string {
+	prefix := p.styles.accent.Render("/ ")
 	if active {
-		cursorChar := styleWithFg(t.Selected).Render("█")
-		queryStr := styleWithFg(t.Selected).Render(query)
+		cursorChar := p.styles.selected.Render("█")
+		queryStr := p.styles.selected.Render(query)
 		line := prefix + queryStr + cursorChar
 		if matchCount > 0 {
-			counter := styleWithFg(t.StatusDim).Render(fmt.Sprintf("  (%d/%d)", cursor+1, matchCount))
+			counter := p.styles.statusDimRaw.Render(fmt.Sprintf("  (%d/%d)", cursor+1, matchCount))
 			line += counter
 		} else if query != "" {
-			line += styleWithFg(t.StatusDim).Render("  (no matches)")
+			line += p.styles.statusDimRaw.Render("  (no matches)")
 		}
 		return line
 	}
-	queryStr := styleWithFg(t.Selected).Render(query)
+	queryStr := p.styles.selected.Render(query)
 	var counter string
 	if matchCount > 0 {
-		counter = styleWithFg(t.StatusDim).Render(fmt.Sprintf("  (%d/%d)", cursor+1, matchCount))
+		counter = p.styles.statusDimRaw.Render(fmt.Sprintf("  (%d/%d)", cursor+1, matchCount))
 	} else {
-		counter = styleWithFg(t.StatusDim).Render("  (no matches)")
+		counter = p.styles.statusDimRaw.Render("  (no matches)")
 	}
-	hint := styleWithFg(t.Unchanged).Render("  [Esc clear]")
+	hint := p.styles.unchanged.Render("  [Esc clear]")
 	line := prefix + queryStr + counter + hint
 	if lipgloss.Width(line) > maxWidth {
 		line = prefix + queryStr + counter
diff --git a/tui/layers.go b/tui/layers.go
index 5c55284..8097d22 100644
--- a/tui/layers.go
+++ b/tui/layers.go
@@ -11,7 +11,7 @@ import (
 	"github.com/deveshctl/layerx/image"
 )
 
-func renderLayers(t Theme, layers []image.Layer, cursor int, offset int, width, height int, focused bool, mode sizeColMode, finalLiveSize int64) string {
+func renderLayers(t Theme, st themeStyles, layers []image.Layer, cursor int, offset int, width, height int, focused bool, mode sizeColMode, finalLiveSize int64) string {
 	contentWidth := width - 2
 	listHeight := height
 
@@ -32,7 +32,7 @@ func renderLayers(t Theme, layers []image.Layer, cursor int, offset int, width,
 	var sb strings.Builder
 
 	for i, layer := range visible {
-		line := formatLayerLine(t, layer, offset+i == cursor, contentWidth, effMode, finalLiveSize)
+		line := formatLayerLine(t, st, layer, offset+i == cursor, contentWidth, effMode, finalLiveSize)
 		sb.WriteString(line)
 		if i < len(visible)-1 {
 			sb.WriteString("\n")
@@ -61,7 +61,7 @@ func renderLayers(t Theme, layers []image.Layer, cursor int, offset int, width,
 	return renderPanel(t, content, title, focused, contentWidth, height, hasAbove, hasBelow)
 }
 
-func renderCommandBar(t Theme, cmd string, width int) string {
+func renderCommandBar(st themeStyles, cmd string, width int) string {
 	maxLines := 3
 	wrappedLines := wrapCommandLines(cmd, width-2, maxLines)
 
@@ -76,16 +76,16 @@ func renderCommandBar(t Theme, cmd string, width int) string {
 		}
 	}
 
-	prefix := lipgloss.NewStyle().Foreground(t.Accent).Bold(true).Render("▶ ")
+	prefix := st.accent.Bold(true).Render("▶ ")
 
 	var sb strings.Builder
 	for i := range filled {
 		wl := wrappedLines[i]
 		if i == 0 {
-			styled := highlightInstruction(t, wl)
+			styled := highlightInstruction(st, wl)
 			sb.WriteString(prefix + styled)
 		} else {
-			sb.WriteString("  " + styleWithFg(t.Command).Render(wl))
+			sb.WriteString("  " + st.command.Render(wl))
 		}
 		if i < filled-1 {
 			sb.WriteString("\n")
@@ -94,16 +94,16 @@ func renderCommandBar(t Theme, cmd string, width int) string {
 	return sb.String()
 }
 
-func highlightInstruction(t Theme, line string) string {
+func highlightInstruction(st themeStyles, line string) string {
 	parts := strings.SplitN(line, " ", 2)
 	if len(parts) == 0 {
 		return ""
 	}
-	instruction := lipgloss.NewStyle().Foreground(t.Accent).Bold(true).Render(parts[0])
+	instruction := st.accent.Bold(true).Render(parts[0])
 	if len(parts) == 1 {
 		return instruction
 	}
-	return instruction + " " + styleWithFg(t.Command).Render(parts[1])
+	return instruction + " " + st.command.Render(parts[1])
 }
 
 func wrapCommandLines(cmd string, width int, maxLines int) []string {
@@ -183,7 +183,7 @@ func deltaColor(t Theme, delta int64, finalLiveSize int64) color.Color {
 	return t.HeaderDim
 }
 
-func formatLayerLine(t Theme, l image.Layer, selected bool, maxWidth int, mode sizeColMode, finalLiveSize int64) string {
+func formatLayerLine(t Theme, st themeStyles, l image.Layer, selected bool, maxWidth int, mode sizeColMode, finalLiveSize int64) string {
 	index := fmt.Sprintf("#%d", l.Index)
 
 	indexWidth := max(len([]rune(index)), 3)
@@ -210,26 +210,26 @@ func formatLayerLine(t Theme, l image.Layer, selected bool, maxWidth int, mode s
 	}
 
 	if selected {
-		cursor := lipgloss.NewStyle().Foreground(t.Accent).Render("▸")
+		cursor := st.accent.Render("▸")
 		plain := " " + index + indexPad + "  " + sizeText + "  " + cmd
 		if lipgloss.Width(plain) > maxWidth-1 {
 			plain = ansi.Truncate(plain, maxWidth-1, "")
 		}
-		inner := cursor + lipgloss.NewStyle().Foreground(t.Selected).Background(t.SelectedBg).Render(plain)
+		inner := cursor + st.selectedTreeBg.Render(plain)
 		return inner
 	}
 
-	dimHash := styleWithFg(t.MetaDim).Render("#")
+	dimHash := st.metaDim.Render("#")
 	numStr := fmt.Sprintf("%d", l.Index)
 	numPad := ""
 	if len([]rune(numStr))+1 < indexWidth {
 		numPad = strings.Repeat(" ", indexWidth-len([]rune(numStr))-1)
 	}
 
-	sizeRendered := renderSizeColumn(t, l, mode, finalLiveSize)
-	cmdRendered := styleWithFg(t.Command).Render(cmd)
+	sizeRendered := renderSizeColumn(t, st, l, mode, finalLiveSize)
+	cmdRendered := st.command.Render(cmd)
 
-	plain := "   " + dimHash + styleWithFg(t.FileName).Render(numStr) + numPad + "  " + sizeRendered + "  " + cmdRendered
+	plain := "   " + dimHash + st.fileName.Render(numStr) + numPad + "  " + sizeRendered + "  " + cmdRendered
 
 	lineWidth := lipgloss.Width(plain)
 	if lineWidth > maxWidth {
@@ -241,18 +241,18 @@ func formatLayerLine(t Theme, l image.Layer, selected bool, maxWidth int, mode s
 // renderSizeColumn produces the colored size column for the unselected
 // row state. Selected rows use the inverted background and skip per-cell
 // coloring to keep the highlight uniform.
-func renderSizeColumn(t Theme, l image.Layer, mode sizeColMode, finalLiveSize int64) string {
+func renderSizeColumn(t Theme, st themeStyles, l image.Layer, mode sizeColMode, finalLiveSize int64) string {
 	switch mode {
 	case sizeColBlob:
 		blob := image.FormatBytes(l.Size)
 		w := max(len([]rune(blob)), 7)
-		return styleWithFg(t.HeaderDim).Render(padLeftRunes(blob, w))
+		return st.headerDim.Render(padLeftRunes(blob, w))
 	case sizeColBoth:
 		blob := image.FormatBytes(l.Size)
 		delta := image.FormatSignedBytes(l.NetDelta)
 		bw := max(len([]rune(blob)), 7)
 		dw := max(len([]rune(delta)), 7)
-		blobR := styleWithFg(t.HeaderDim).Render(padLeftRunes(blob, bw))
+		blobR := st.headerDim.Render(padLeftRunes(blob, bw))
 		deltaR := styleWithFg(deltaColor(t, l.NetDelta, finalLiveSize)).Render(padLeftRunes(delta, dw))
 		return blobR + " " + deltaR
 	default:
diff --git a/tui/layers_test.go b/tui/layers_test.go
index 806c63a..f617223 100644
--- a/tui/layers_test.go
+++ b/tui/layers_test.go
@@ -22,7 +22,7 @@ func TestFormatLayerLine_DeltaMode_HasSignedColumn(t *testing.T) {
 	// Use exact binary-MB multiples so FormatBytes emits clean values.
 	const mb = 1024 * 1024
 	l := makeLayer(1, 5*mb, 3*mb, "RUN apt-get install foo")
-	out := formatLayerLine(CatppuccinMocha(), l, false, 60, sizeColDelta, 30*mb)
+	out := formatLayerLine(CatppuccinMocha(), themeStyles{}, l, false, 60, sizeColDelta, 30*mb)
 	// Should contain the signed delta string somewhere.
 	assert.Contains(t, out, "+3.0 MB")
 	// Should NOT contain the blob value when in delta mode.
@@ -32,7 +32,7 @@ func TestFormatLayerLine_DeltaMode_HasSignedColumn(t *testing.T) {
 func TestFormatLayerLine_BlobMode_RegressionGuard(t *testing.T) {
 	const mb = 1024 * 1024
 	l := makeLayer(1, 5*mb, 3*mb, "RUN apt-get install foo")
-	out := formatLayerLine(CatppuccinMocha(), l, false, 60, sizeColBlob, 30*mb)
+	out := formatLayerLine(CatppuccinMocha(), themeStyles{}, l, false, 60, sizeColBlob, 30*mb)
 	// Blob value should appear; signed delta should NOT.
 	assert.Contains(t, out, "5.0 MB")
 	assert.NotContains(t, out, "+3.0 MB")
@@ -41,7 +41,7 @@ func TestFormatLayerLine_BlobMode_RegressionGuard(t *testing.T) {
 func TestFormatLayerLine_BothMode_HasBothValues(t *testing.T) {
 	const mb = 1024 * 1024
 	l := makeLayer(1, 5*mb, 3*mb, "RUN apt-get install foo")
-	out := formatLayerLine(CatppuccinMocha(), l, false, 80, sizeColBoth, 30*mb)
+	out := formatLayerLine(CatppuccinMocha(), themeStyles{}, l, false, 80, sizeColBoth, 30*mb)
 	assert.Contains(t, out, "5.0 MB")
 	assert.Contains(t, out, "+3.0 MB")
 }
@@ -49,7 +49,7 @@ func TestFormatLayerLine_BothMode_HasBothValues(t *testing.T) {
 func TestFormatLayerLine_NegativeDeltaRendersWithMinus(t *testing.T) {
 	const mb = 1024 * 1024
 	l := makeLayer(2, 1*mb, -2*mb, "RUN apt-get clean")
-	out := formatLayerLine(CatppuccinMocha(), l, false, 60, sizeColDelta, 30*mb)
+	out := formatLayerLine(CatppuccinMocha(), themeStyles{}, l, false, 60, sizeColDelta, 30*mb)
 	assert.Contains(t, out, "-2.0 MB")
 }
 
@@ -60,7 +60,7 @@ func TestRenderLayers_BothMode_FallsBackToDelta_OnNarrowPanel(t *testing.T) {
 		makeLayer(1, 200_000, -2*mb, "RUN clean"),
 	}
 	// width = 36 → contentWidth = 34, below the < 38 fallback threshold.
-	out := renderLayers(CatppuccinMocha(), layers, 0, 0, 36, 10, true, sizeColBoth, 8*mb)
+	out := renderLayers(CatppuccinMocha(), themeStyles{}, layers, 0, 0, 36, 10, true, sizeColBoth, 8*mb)
 	// In delta-only fallback the blob value (5.0 MB) must be hidden;
 	// only the signed delta column is rendered.
 	assert.NotContains(t, out, " 5.0 MB", "blob value (unsigned) must not appear in delta-fallback")
@@ -69,14 +69,14 @@ func TestRenderLayers_BothMode_FallsBackToDelta_OnNarrowPanel(t *testing.T) {
 
 func TestRenderLayers_FocusedTitle_ReflectsSizeMode(t *testing.T) {
 	layers := []image.Layer{makeLayer(0, 1000, 1000, "FROM scratch")}
-	out := renderLayers(CatppuccinMocha(), layers, 0, 0, 60, 5, true, sizeColDelta, 1000)
+	out := renderLayers(CatppuccinMocha(), themeStyles{}, layers, 0, 0, 60, 5, true, sizeColDelta, 1000)
 	assert.Contains(t, out, sizeModeLabelChange)
 
-	out = renderLayers(CatppuccinMocha(), layers, 0, 0, 60, 5, true, sizeColBlob, 1000)
+	out = renderLayers(CatppuccinMocha(), themeStyles{}, layers, 0, 0, 60, 5, true, sizeColBlob, 1000)
 	assert.Contains(t, out, sizeModeLabelStored)
 	assert.False(t, strings.Contains(out, sizeModeLabelChange), "stored mode title should not show change label")
 
-	out = renderLayers(CatppuccinMocha(), layers, 0, 0, 60, 5, true, sizeColBoth, 1000)
+	out = renderLayers(CatppuccinMocha(), themeStyles{}, layers, 0, 0, 60, 5, true, sizeColBoth, 1000)
 	assert.Contains(t, out, sizeModeLabelBoth)
 }
 
diff --git a/tui/model.go b/tui/model.go
index 88a734f..5ad0b2f 100644
--- a/tui/model.go
+++ b/tui/model.go
@@ -297,6 +297,9 @@ type model struct {
 	// treeCache memoizes displayTreeFor across frames. Behind a pointer so the
 	// value-receiver method can write through it and all model copies share it.
 	treeCache *treeCache
+	// styles holds lipgloss.Style values derived from the session theme.
+	// Built once in NewModel; reused every frame to avoid per-call allocation.
+	styles themeStyles
 
 	fetchCtx    context.Context
 	fetchCancel context.CancelFunc
@@ -343,7 +346,8 @@ func NewModel(cfg Config) model {
 		noCache:     cfg.NoCache,
 		theme:       theme,
 		transparentBg: cfg.TransparentBg,
-		treeCache:   &treeCache{},
+		treeCache:        &treeCache{},
+		styles:           newThemeStyles(theme),
 		renderedImageRef: renderGradient(cfg.ImageRef, theme.GradientStart, theme.GradientEnd),
 		fetchCtx:    ctx,
 		fetchCancel: cancel,
@@ -1705,7 +1709,7 @@ func (m model) viewLoading() tea.View {
 
 	var lines []string
 	lines = append(lines, "")
-	lines = append(lines, "  "+lipgloss.NewStyle().Foreground(m.theme.Accent).Bold(true).Render("◆ layerx"))
+	lines = append(lines, "  "+m.styles.accent.Bold(true).Render("◆ layerx"))
 	lines = append(lines, "")
 
 	switch m.loadPhase {
@@ -1730,8 +1734,8 @@ func (m model) viewLoading() tea.View {
 				}
 				if barWidth >= 4 {
 					filled := barWidth * pct / 100
-					bar := lipgloss.NewStyle().Foreground(m.theme.Accent).Render(strings.Repeat("━", filled)) +
-						lipgloss.NewStyle().Foreground(m.theme.Separator).Render(strings.Repeat("─", barWidth-filled))
+					bar := m.styles.accent.Render(strings.Repeat("━", filled)) +
+						m.styles.separator.Render(strings.Repeat("─", barWidth-filled))
 					detail += fmt.Sprintf("  [%s]%s", bar, bytesText)
 				} else {
 					detail += bytesText
@@ -1764,8 +1768,7 @@ func (m model) viewLoading() tea.View {
 	}
 
 	lines = append(lines, "")
-	hintStyle := lipgloss.NewStyle().Foreground(m.theme.StatusDim)
-	lines = append(lines, "  "+hintStyle.Render("Press q or Esc to exit."))
+	lines = append(lines, "  "+m.styles.statusDimRaw.Render("Press q or Esc to exit."))
 	lines = append(lines, "")
 
 	boxWidth := 52
@@ -1798,7 +1801,7 @@ func (m model) viewLoading() tea.View {
 func (m model) renderRightPanel(width, height int) string {
 	if !m.aggregated {
 		treeFiles := m.displayTreeFor(focusTree)
-		return renderFileTree(m.theme, treeFiles, m.treeCursor, m.treeOffset,
+		return renderFileTree(m.theme, m.styles, treeFiles, m.treeCursor, m.treeOffset,
 			width, height, m.focus == focusTree, m.filterActive,
 			m.filterQuery, m.useTreeCollapse(), false,
 			m.treeCollapsed, m.layerCursor)
@@ -1807,6 +1810,7 @@ func (m model) renderRightPanel(width, height int) string {
 	botFiles := m.displayTreeFor(focusTreeAgg)
 	return renderSplitFileTree(splitTreeInput{
 		theme:        m.theme,
+		styles:       m.styles,
 		width:        width,
 		height:       height,
 		currentLayer: m.layerCursor,
@@ -1837,8 +1841,7 @@ func (m model) viewError() tea.View {
 		wrapWidth = 1
 	}
 	errStyle := lipgloss.NewStyle().Foreground(m.theme.Removed).Bold(true).Width(wrapWidth)
-	hintStyle := lipgloss.NewStyle().Foreground(m.theme.StatusDim)
-	msg := errStyle.Render("Error: "+m.errMsg) + "\n\n" + hintStyle.Render("Press q or Esc to exit.")
+	msg := errStyle.Render("Error: "+m.errMsg) + "\n\n" + m.styles.statusDimRaw.Render("Press q or Esc to exit.")
 	content := lipgloss.Place(m.width, m.height, lipgloss.Center, lipgloss.Center, msg)
 	return finalizeView(tea.NewView(content), m.viewBg())
 }
@@ -1869,7 +1872,7 @@ func (m model) viewReady() tea.View {
 	if m.viewState == viewNone {
 		treeFiles = m.displayTree()
 	}
-	left := renderLayers(m.theme, m.layers(), m.layerCursor, m.layerOffset, leftWidth, panelHeight, m.focus == focusLayers, m.sizeMode, m.finalLiveSize())
+	left := renderLayers(m.theme, m.styles, m.layers(), m.layerCursor, m.layerOffset, leftWidth, panelHeight, m.focus == focusLayers, m.sizeMode, m.finalLiveSize())
 	right := m.renderRightPanel(rightWidth, panelHeight)
 
 	panels := lipgloss.JoinHorizontal(lipgloss.Top, left, " ", right)
@@ -1894,6 +1897,7 @@ func (m model) viewReady() tea.View {
 			searchActive:  m.viewSearchActive,
 			highlightedLines: m.viewHighlightedLines,
 			theme:            m.theme,
+			styles:           m.styles,
 		})
 		panels = viewer
 	}
@@ -1903,9 +1907,9 @@ func (m model) viewReady() tea.View {
 	if m.layerCursor < len(layers) {
 		cmd = layers[m.layerCursor].Command
 	}
-	commandBar := renderCommandBar(m.theme, cmd, m.width)
+	commandBar := renderCommandBar(m.styles, cmd, m.width)
 
-	sep := lipgloss.NewStyle().Foreground(m.theme.Separator).Render(strings.Repeat("─", m.width))
+	sep := m.styles.separator.Render(strings.Repeat("─", m.width))
 	status := m.renderStatusBar(treeFiles)
 
 	content := lipgloss.JoinVertical(lipgloss.Left, header, panels, commandBar, sep, status)
@@ -1943,36 +1947,34 @@ func (m model) leftPanelWidth() int {
 }
 
 func (m model) renderHeader() string {
-	glyph := lipgloss.NewStyle().Foreground(m.theme.Accent).Background(m.theme.StatusBg).Render("◆")
-	brand := lipgloss.NewStyle().Foreground(m.theme.Accent).Background(m.theme.StatusBg).Bold(true).Render(" layerx")
-	sep := lipgloss.NewStyle().Foreground(m.theme.HeaderSep).Background(m.theme.StatusBg).Render(" │ ")
-	imageName := lipgloss.NewStyle().Background(m.theme.StatusBg).Render(m.renderedImageRef)
+	glyph := m.styles.accentBg.Render("◆")
+	brand := m.styles.accentBg.Bold(true).Render(" layerx")
+	sep := m.styles.headerSep.Render(" │ ")
+	imageName := m.styles.bgOnly.Render(m.renderedImageRef)
 	left := glyph + brand + sep + imageName
 	// Append the active platform after the image name when --platform is
 	// set. Multi-platform images otherwise give no visual cue which variant
 	// is on screen — easy to misread an arm64 layout as amd64.
 	if m.platform != "" {
-		platformStyle := lipgloss.NewStyle().Foreground(m.theme.HeaderDim).Background(m.theme.StatusBg)
-		left += sep + platformStyle.Render(m.platform)
+		left += sep + m.styles.headerDimBg.Render(m.platform)
 	}
 
 	totalSize := image.FormatBytes(m.analysis.TotalSize)
 	layerCount := fmt.Sprintf("%d layers", len(m.analysis.Layers))
-	right := lipgloss.NewStyle().Foreground(m.theme.HeaderDim).Background(m.theme.StatusBg).Render(layerCount + " · " + totalSize)
+	right := m.styles.headerDimBg.Render(layerCount + " · " + totalSize)
 
 	gap := max(m.width-lipgloss.Width(left)-lipgloss.Width(right)-1, 1)
 
-	bgStyle := lipgloss.NewStyle().Background(m.theme.StatusBg)
-	return bgStyle.Render(" " + left + strings.Repeat(" ", gap) + right)
+	return m.styles.bgOnly.Render(" " + left + strings.Repeat(" ", gap) + right)
 }
 
 func (m model) renderStatusBar(treeFiles []*image.FileNode) string {
 	if m.viewState != viewNone {
 		return m.renderViewerStatusBar()
 	}
-	keyStyle := lipgloss.NewStyle().Foreground(m.theme.StatusKey).Background(m.theme.StatusBg).Bold(true)
-	descStyle := lipgloss.NewStyle().Foreground(m.theme.StatusDim).Background(m.theme.StatusBg)
-	sepStyle := lipgloss.NewStyle().Foreground(m.theme.HeaderSep).Background(m.theme.StatusBg)
+	keyStyle := m.styles.statusKey
+	descStyle := m.styles.statusDim
+	sepStyle := m.styles.headerSep
 
 	type hint struct{ key, desc string }
 	var hints []hint
@@ -2032,15 +2034,13 @@ func (m model) renderStatusBar(treeFiles []*image.FileNode) string {
 	layers := m.layers()
 	var right string
 	if m.statusMsg != "" {
-		fg := m.theme.Added
+		msgStyle := m.styles.addedBg
 		if strings.HasPrefix(m.statusMsg, "Error:") {
-			fg = m.theme.Removed
+			msgStyle = m.styles.removedStatusBg
 		}
-		msgStyle := lipgloss.NewStyle().Foreground(fg).Background(m.theme.StatusBg).Bold(true)
 		right = msgStyle.Render(m.statusMsg) + " "
 	} else if m.copyConfirm {
-		copiedStyle := lipgloss.NewStyle().Foreground(m.theme.Added).Background(m.theme.StatusBg).Bold(true)
-		right = copiedStyle.Render("Copied!") + " "
+		right = m.styles.addedBg.Render("Copied!") + " "
 	} else {
 		badges := ""
 		if m.efficiency != nil {
@@ -2049,19 +2049,19 @@ func (m model) renderStatusBar(treeFiles []*image.FileNode) string {
 			if m.efficiency.WastedBytes > 0 {
 				effStr += " · " + image.FormatBytes(m.efficiency.WastedBytes) + " wasted"
 			}
-			badges += lipgloss.NewStyle().Foreground(m.theme.Accent).Background(m.theme.StatusBg).Render("["+effStr+"]") + " "
+			badges += m.styles.accentBg.Render("["+effStr+"]") + " "
 		}
 		if m.diffOnly {
-			badges += lipgloss.NewStyle().Foreground(m.theme.Modified).Background(m.theme.StatusBg).Render("[diff]") + " "
+			badges += m.styles.modifiedBg.Render("[diff]") + " "
 		}
 		if m.aggregated {
-			badges += lipgloss.NewStyle().Foreground(m.theme.Accent).Background(m.theme.StatusBg).Render("[split]") + " "
+			badges += m.styles.accentBg.Render("[split]") + " "
 		}
 		switch m.sortMode {
 		case sortDesc:
-			badges += lipgloss.NewStyle().Foreground(m.theme.Accent).Background(m.theme.StatusBg).Render("[↓size]") + " "
+			badges += m.styles.accentBg.Render("[↓size]") + " "
 		case sortAsc:
-			badges += lipgloss.NewStyle().Foreground(m.theme.Accent).Background(m.theme.StatusBg).Render("[↑size]") + " "
+			badges += m.styles.accentBg.Render("[↑size]") + " "
 		}
 
 		layerNum := fmt.Sprintf("%d", m.layerCursor+1)
@@ -2070,7 +2070,7 @@ func (m model) renderStatusBar(treeFiles []*image.FileNode) string {
 		if m.layerCursor < len(layers) {
 			size = image.FormatBytes(layers[m.layerCursor].Size)
 		}
-		rightHighlight := lipgloss.NewStyle().Foreground(m.theme.Selected).Background(m.theme.StatusBg).Bold(true).Render("Layer " + layerNum)
+		rightHighlight := m.styles.selectedStatusBg.Render("Layer " + layerNum)
 		sizeLabel := "stored " + size
 		if m.focus == focusLayers && m.layerCursor < len(layers) {
 			switch m.sizeMode {
@@ -2080,20 +2080,19 @@ func (m model) renderStatusBar(treeFiles []*image.FileNode) string {
 				sizeLabel = "stored " + size + " · change " + image.FormatSignedBytes(layers[m.layerCursor].NetDelta)
 			}
 		}
-		rightDim := lipgloss.NewStyle().Foreground(m.theme.StatusDim).Background(m.theme.StatusBg).Render("/" + layerTotal + " · " + sizeLabel)
+		rightDim := m.styles.statusDim.Render("/" + layerTotal + " · " + sizeLabel)
 		right = badges + rightHighlight + rightDim + " "
 	}
 
 	gap := max(m.width-lipgloss.Width(hintStr)-lipgloss.Width(right), 0)
 
-	bgStyle := lipgloss.NewStyle().Background(m.theme.StatusBg)
-	return bgStyle.Render(hintStr + strings.Repeat(" ", gap) + right)
+	return m.styles.bgOnly.Render(hintStr + strings.Repeat(" ", gap) + right)
 }
 
 func (m model) renderViewerStatusBar() string {
-	keyStyle := lipgloss.NewStyle().Foreground(m.theme.StatusKey).Background(m.theme.StatusBg).Bold(true)
-	descStyle := lipgloss.NewStyle().Foreground(m.theme.StatusDim).Background(m.theme.StatusBg)
-	sepStyle := lipgloss.NewStyle().Foreground(m.theme.HeaderSep).Background(m.theme.StatusBg)
+	keyStyle := m.styles.statusKey
+	descStyle := m.styles.statusDim
+	sepStyle := m.styles.headerSep
 
 	hints := " " +
 		keyStyle.Render("j/k") + " " + descStyle.Render("up/down") + " " +
@@ -2112,10 +2111,9 @@ func (m model) renderViewerStatusBar() string {
 
 	var right string
 	if m.copyConfirm {
-		copiedStyle := lipgloss.NewStyle().Foreground(m.theme.Added).Background(m.theme.StatusBg).Bold(true)
-		right = copiedStyle.Render("Copied!") + " "
+		right = m.styles.addedBg.Render("Copied!") + " "
 	} else if len(m.viewSearchMatches) > 0 {
-		matchStyle := lipgloss.NewStyle().Foreground(m.theme.SearchCurrentBg).Background(m.theme.StatusBg).Bold(true)
+		matchStyle := m.styles.searchMatchStyle
 		right = matchStyle.Render(fmt.Sprintf("Match %d/%d ", m.viewSearchCursor+1, len(m.viewSearchMatches)))
 	} else if m.viewContent != nil && !m.viewContent.Binary && len(m.viewContent.Data) > 0 {
 		total := m.viewLineCount()
@@ -2124,14 +2122,12 @@ func (m model) renderViewerStatusBar() string {
 		if total > 0 {
 			pct = line * 100 / total
 		}
-		rightDim := lipgloss.NewStyle().Foreground(m.theme.StatusDim).Background(m.theme.StatusBg)
-		right = rightDim.Render(fmt.Sprintf("Line %d/%d (%d%%) ", line, total, pct))
+		right = m.styles.statusDim.Render(fmt.Sprintf("Line %d/%d (%d%%) ", line, total, pct))
 	}
 
 	gap := max(m.width-lipgloss.Width(hints)-lipgloss.Width(right), 0)
 
-	bgStyle := lipgloss.NewStyle().Background(m.theme.StatusBg)
-	return bgStyle.Render(hints + strings.Repeat(" ", gap) + right)
+	return m.styles.bgOnly.Render(hints + strings.Repeat(" ", gap) + right)
 }
 
 func (m model) fetchFileContent(ctx context.Context, path string, requestID uint64) tea.Cmd {
diff --git a/tui/model_test.go b/tui/model_test.go
index a84e95c..40e2a24 100644
--- a/tui/model_test.go
+++ b/tui/model_test.go
@@ -763,13 +763,13 @@ func TestFriendlyErrorGenericReturnsMessage(t *testing.T) {
 func TestRenderLayersDoesNotPanic(t *testing.T) {
 	a := testAnalysis()
 	assert.NotPanics(t, func() {
-		renderLayers(CatppuccinMocha(), a.Layers, 0, 0, 40, 20, true, sizeColDelta, 0)
+		renderLayers(CatppuccinMocha(), themeStyles{}, a.Layers, 0, 0, 40, 20, true, sizeColDelta, 0)
 	})
 }
 
 func TestRenderLayersEmptyDoesNotPanic(t *testing.T) {
 	assert.NotPanics(t, func() {
-		renderLayers(CatppuccinMocha(), nil, 0, 0, 40, 20, false, sizeColDelta, 0)
+		renderLayers(CatppuccinMocha(), themeStyles{}, nil, 0, 0, 40, 20, false, sizeColDelta, 0)
 	})
 }
 
@@ -779,12 +779,12 @@ func TestRenderFileTreeDoesNotPanic(t *testing.T) {
 	m := setupModel()
 	files := m.displayTree()
 	assert.NotPanics(t, func() {
-		renderFileTree(CatppuccinMocha(), files, 0, 0, 60, 20, true, false, "", true, false, nil, 0)
+		renderFileTree(CatppuccinMocha(), themeStyles{}, files, 0, 0, 60, 20, true, false, "", true, false, nil, 0)
 	})
 }
 
 func TestRenderFileTreeEmptyShowsPlaceholder(t *testing.T) {
-	output := renderFileTree(CatppuccinMocha(), nil, 0, 0, 60, 20, false, false, "", true, false, nil, 0)
+	output := renderFileTree(CatppuccinMocha(), themeStyles{}, nil, 0, 0, 60, 20, false, false, "", true, false, nil, 0)
 	assert.Contains(t, output, "no filesystem changes")
 }
 
@@ -800,7 +800,7 @@ func TestRenderFileTreeCollapsedDirShowsGlyph(t *testing.T) {
 	}
 	updated, _ := m.Update(tea.KeyPressMsg{Code: tea.KeyEnter})
 	um := updated.(model)
-	line := renderFileTree(CatppuccinMocha(), um.displayTree(), um.treeCursor, 0, 80, 20, true, false, "", true, false, um.treeCollapsed, 0)
+	line := renderFileTree(CatppuccinMocha(), themeStyles{}, um.displayTree(), um.treeCursor, 0, 80, 20, true, false, "", true, false, um.treeCollapsed, 0)
 	assert.Contains(t, line, "▸")
 }
 
diff --git a/tui/styles.go b/tui/styles.go
index 6af4df0..f233fe7 100644
--- a/tui/styles.go
+++ b/tui/styles.go
@@ -92,6 +92,99 @@ func styleWithFg(c color.Color) lipgloss.Style {
 	return lipgloss.NewStyle().Foreground(c)
 }
 
+// themeStyles holds lipgloss.Style values derived solely from the session
+// Theme. The theme is fixed at NewModel time and never changes, so these
+// styles are built once and reused for every frame instead of being
+// allocated anew on each styleWithFg / lipgloss.NewStyle() call.
+//
+// Dynamic styles — those whose color or content depends on per-row state
+// (selected background, diff color, delta color, search highlight with a
+// per-row fg) — are NOT included here; they remain inline at their call
+// sites.
+type themeStyles struct {
+	// file tree
+	metaDim   lipgloss.Style
+	headerDim lipgloss.Style
+	treeDim   lipgloss.Style
+	unchanged lipgloss.Style
+	added     lipgloss.Style
+	modified  lipgloss.Style
+	removed   lipgloss.Style
+	accent    lipgloss.Style
+	fileName  lipgloss.Style
+	// status / header bar chrome (with StatusBg background)
+	statusKey   lipgloss.Style
+	statusDim   lipgloss.Style
+	headerSep   lipgloss.Style
+	headerDimBg lipgloss.Style
+	accentBg    lipgloss.Style
+	modifiedBg  lipgloss.Style
+	addedBg     lipgloss.Style
+	bgOnly      lipgloss.Style
+	// misc
+	command      lipgloss.Style
+	separator    lipgloss.Style
+	selected     lipgloss.Style
+	statusDimRaw lipgloss.Style // StatusDim without StatusBg (loading/error screens)
+	// searchHighlight is the background used for non-current search matches
+	// in both the file tree name and the file viewer.
+	searchHighlight lipgloss.Style
+	// searchHighlightFile is FileName+SearchHighlightBg, used for non-current
+	// match segments in the file viewer where the fg is always FileName.
+	searchHighlightFile lipgloss.Style
+	// cursorOverlay is the style applied to the character under the file-viewer
+	// cursor. Both inputs (SearchCurrentFg, Accent) are immutable for the session.
+	cursorOverlay lipgloss.Style
+	// selectedStatusBg is Selected+StatusBg+Bold, used for the layer number in
+	// the status bar right section.
+	selectedStatusBg lipgloss.Style
+	// selectedTreeBg is Selected+SelectedBg, used for the selected row in the
+	// file tree and layer list.
+	selectedTreeBg lipgloss.Style
+	// searchMatchStyle is SearchCurrentBg+StatusBg+Bold, used for the match
+	// counter in the viewer status bar.
+	searchMatchStyle lipgloss.Style
+	// searchCurrentLine is SearchCurrentFg+SearchCurrentBg, used for the
+	// current search match segment in the file viewer.
+	searchCurrentLine lipgloss.Style
+	// removedStatusBg is Removed+StatusBg+Bold, used for the error status message.
+	removedStatusBg lipgloss.Style
+}
+
+func newThemeStyles(t Theme) themeStyles {
+	return themeStyles{
+		metaDim:          lipgloss.NewStyle().Foreground(t.MetaDim),
+		headerDim:        lipgloss.NewStyle().Foreground(t.HeaderDim),
+		treeDim:          lipgloss.NewStyle().Foreground(t.TreeDim),
+		unchanged:        lipgloss.NewStyle().Foreground(t.Unchanged),
+		added:            lipgloss.NewStyle().Foreground(t.Added),
+		modified:         lipgloss.NewStyle().Foreground(t.Modified),
+		removed:          lipgloss.NewStyle().Foreground(t.Removed),
+		accent:           lipgloss.NewStyle().Foreground(t.Accent),
+		fileName:         lipgloss.NewStyle().Foreground(t.FileName),
+		statusKey:        lipgloss.NewStyle().Foreground(t.StatusKey).Background(t.StatusBg).Bold(true),
+		statusDim:        lipgloss.NewStyle().Foreground(t.StatusDim).Background(t.StatusBg),
+		headerSep:        lipgloss.NewStyle().Foreground(t.HeaderSep).Background(t.StatusBg),
+		headerDimBg:      lipgloss.NewStyle().Foreground(t.HeaderDim).Background(t.StatusBg),
+		accentBg:         lipgloss.NewStyle().Foreground(t.Accent).Background(t.StatusBg),
+		modifiedBg:       lipgloss.NewStyle().Foreground(t.Modified).Background(t.StatusBg),
+		addedBg:          lipgloss.NewStyle().Foreground(t.Added).Background(t.StatusBg).Bold(true),
+		bgOnly:           lipgloss.NewStyle().Background(t.StatusBg),
+		command:          lipgloss.NewStyle().Foreground(t.Command),
+		separator:        lipgloss.NewStyle().Foreground(t.Separator),
+		selected:         lipgloss.NewStyle().Foreground(t.Selected),
+		statusDimRaw:     lipgloss.NewStyle().Foreground(t.StatusDim),
+		searchHighlight:     lipgloss.NewStyle().Background(t.SearchHighlightBg),
+		searchHighlightFile: lipgloss.NewStyle().Foreground(t.FileName).Background(t.SearchHighlightBg),
+		cursorOverlay:    lipgloss.NewStyle().Foreground(t.SearchCurrentFg).Background(t.Accent),
+		selectedStatusBg:  lipgloss.NewStyle().Foreground(t.Selected).Background(t.StatusBg).Bold(true),
+		selectedTreeBg:    lipgloss.NewStyle().Foreground(t.Selected).Background(t.SelectedBg),
+		searchMatchStyle:  lipgloss.NewStyle().Foreground(t.SearchCurrentBg).Background(t.StatusBg).Bold(true),
+		searchCurrentLine: lipgloss.NewStyle().Foreground(t.SearchCurrentFg).Background(t.SearchCurrentBg),
+		removedStatusBg:   lipgloss.NewStyle().Foreground(t.Removed).Background(t.StatusBg).Bold(true),
+	}
+}
+
 // renderGradient interpolates linearly from `from` to `to` across the runes
 // of text, rendering each rune in its own per-character colour. Single-rune
 // strings get the start colour; the transition is spread evenly across longer

From 08b8a3a17196e84d3e5f1613f64d47adcfd2cc1f Mon Sep 17 00:00:00 2001
From: deveshctl <deveshpharswanhk@gmail.com>
Date: Wed, 5 Aug 2026 15:23:42 +0530
Subject: [PATCH 2/3] style(tui): fix indentation of pad write in empty-tree
 branch

The sb.WriteString(pad) line in renderTreeBody's empty-tree placeholder
was indented one tab short of its sibling statement, a whitespace glitch
introduced alongside the style-cache change. Pure formatting; no behaviour
change.
---
 tui/filetree.go | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tui/filetree.go b/tui/filetree.go
index d124586..e22fbca 100644
--- a/tui/filetree.go
+++ b/tui/filetree.go
@@ -110,7 +110,7 @@ func renderTreeBody(in treePaneInput) (body string, hasAbove, hasBelow bool) {
 		midpoint := contentHeight / 2
 		for i := 0; i < contentHeight; i++ {
 			if i == midpoint {
-			sb.WriteString(pad)
+				sb.WriteString(pad)
 				sb.WriteString(in.styles.unchanged.Render(msg))
 			}
 			if i < contentHeight-1 {

From a98be794a3df22d4a787a31b70b8c8798d4e025d Mon Sep 17 00:00:00 2001
From: deveshctl <deveshpharswanhk@gmail.com>
Date: Wed, 5 Aug 2026 17:27:31 +0530
Subject: [PATCH 3/3] fix(tui): pass styles to bottom pane in split-tree render
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

The botBody treePaneInput literal in renderSplitFileTree was missing
styles: in.styles, so the Cumulative pane in aggregated split mode
rendered with a zero-value themeStyles — no colors, no diff highlighting,
no selection background, no search styling. topBody was correctly
threaded; this brings botBody in line.
---
 tui/filetree.go | 1 +
 1 file changed, 1 insertion(+)

diff --git a/tui/filetree.go b/tui/filetree.go
index e22fbca..c3e87cd 100644
--- a/tui/filetree.go
+++ b/tui/filetree.go
@@ -224,6 +224,7 @@ func renderSplitFileTree(in splitTreeInput) string {
 
 	botBody, botAbove, botBelow := renderTreeBody(treePaneInput{
 		theme:         in.theme,
+		styles:        in.styles,
 		files:         in.botFiles,
 		cursor:        in.botCursor,
 		offset:        in.botOffset,