diff --git a/programs/src/charmap/main.cpp b/programs/src/charmap/main.cpp
index 9e5a601..93cc3d1 100644
--- a/programs/src/charmap/main.cpp
+++ b/programs/src/charmap/main.cpp
@@ -204,9 +204,6 @@ static constexpr int FOOTER_H  = 84;
 static constexpr int GRID_PAD  = 12;
 static constexpr int CELL_GAP  = 6;
 static constexpr int CELL_TARGET = 54;   // desired tile edge in px
-// Gutter reserved on the right of the tile area for the shared MTK scrollbar
-// (its 12px track plus a little breathing room from the last tile column).
-static constexpr int SB_GUTTER = mtk::SCROLLBAR_W + 6;
 
 static constexpr int TAB_SIZE   = 16;
 static constexpr int CELL_SIZE  = 26;    // glyph font size inside a tile
@@ -238,7 +235,8 @@ static const char* g_tab_labels[SET_COUNT] = {};  // populated from SETS in _sta
 
 struct Layout {
     Rect tabs;
-    Rect grid;      // interior area available for the tile grid
+    Rect grid;      // interior area available for the tile grid (with margins)
+    Rect panel;     // full content region between tabs and footer (scrollbar viewport)
     Rect footer;
     Rect copy_btn;
     int  cols;
@@ -255,13 +253,21 @@ static Layout compute_layout(int w, int h) {
     L.tabs   = { 0, 0, w, TAB_H };
     int grid_top = TAB_H;
     L.footer = { 0, h - FOOTER_H, w, FOOTER_H };
+
+    // Scrollbar viewport: the whole panel between tabs and footer, so the
+    // shared MTK scrollbar hugs the window's right edge and spans full height
+    // (matching Devices/Music) — no inset above or beside it.
+    L.panel  = { 0, grid_top, w, (h - FOOTER_H) - grid_top };
+
+    // Tile grid keeps left/top/bottom margins; its right edge leaves the
+    // scrollbar's width plus a GRID_PAD gap.
     L.grid   = { GRID_PAD, grid_top + GRID_PAD,
-                 w - GRID_PAD * 2, (h - FOOTER_H) - grid_top - GRID_PAD * 2 };
+                 w - mtk::SCROLLBAR_W - GRID_PAD * 2,
+                 (h - FOOTER_H) - grid_top - GRID_PAD * 2 };
     if (L.grid.w < CELL_TARGET) L.grid.w = CELL_TARGET;
     if (L.grid.h < 1) L.grid.h = 1;
 
-    int avail = L.grid.w - SB_GUTTER;
-    if (avail < CELL_TARGET) avail = CELL_TARGET;
+    int avail = L.grid.w;
     L.cols = (avail + CELL_GAP) / (CELL_TARGET + CELL_GAP);
     if (L.cols < 1) L.cols = 1;
     L.cell_w = (avail - CELL_GAP * (L.cols - 1)) / L.cols;
@@ -291,7 +297,7 @@ static Rect tile_rect(const Layout& L, int i) {
 
 static int hit_tile(const Layout& L, int mx, int my) {
     if (my < L.grid.y || my >= L.grid.y + L.grid.h) return -1;
-    if (mx < L.grid.x || mx >= L.grid.x + L.grid.w - SB_GUTTER) return -1;
+    if (mx < L.grid.x || mx >= L.grid.x + L.grid.w) return -1;
     for (int i = 0; i < cur_set().count; i++) {
         Rect r = tile_rect(L, i);
         if (r.contains(mx, my)) return i;
@@ -386,7 +392,7 @@ static void render(Canvas& c) {
     }
 
     // ---- Scrollbar (shared MTK widget; no-ops when the set fits) ----
-    Rect sb_track = mtk::scrollbar_track_rect(L.grid);
+    Rect sb_track = mtk::scrollbar_track_rect(L.panel);
     Rect sb_thumb = mtk::scrollbar_thumb_rect(sb_track, L.content_h, L.grid.h, g_scroll);
     mtk::draw_scrollbar(c, sb_track, sb_thumb, g_sb_hover, g_sb_dragging, g_theme);
 
@@ -461,7 +467,7 @@ static bool handle_mouse(const montauk::abi::WinEvent& ev, int w, int h) {
     bool released = !(ev.mouse.buttons & 1) && (ev.mouse.prev_buttons & 1);
 
     // Scrollbar geometry (shared MTK widget).
-    Rect sb_track = mtk::scrollbar_track_rect(L.grid);
+    Rect sb_track = mtk::scrollbar_track_rect(L.panel);
     Rect sb_thumb = mtk::scrollbar_thumb_rect(sb_track, L.content_h, L.grid.h, g_scroll);
     bool scrollable = !sb_track.empty() && !sb_thumb.empty();