diff --git a/src/pp/pp.c b/src/pp/pp.c
index e9cb1621..f9811608 100644
--- a/src/pp/pp.c
+++ b/src/pp/pp.c
@@ -452,7 +452,7 @@ void UpdateUser(P_Window *window)
     //- Begin UI
     UI_BeginBuild();
     UI_Box *pp_root_box = UI_BuildBox(UI_Flag_DrawImage, UI_NilKey);
-    UI_PushParent(pp_root_box);
+    UI_Push(Parent, pp_root_box);
 
     //- Init render data buffers
     if (!g->material_instances_arena)
@@ -2006,10 +2006,12 @@ void UpdateUser(P_Window *window)
         __profn("Draw debug info");
 
         UI_Box *dbg_box = UI_BuildBox(0, UI_NilKey);
-        UI_PushParent(dbg_box);
-        UI_PushSize(Axis_X, UI_SizeKind_Pixel, 5, 0);
-        UI_PushSize(Axis_Y, UI_SizeKind_Pixel, 5, 0);
+        UI_PushCheckpoint();
         {
+            UI_Push(Parent, dbg_box);
+            UI_Push(Width, UI_PixelSize(5, 0));
+            UI_Push(Height, UI_PixelSize(5, 0));
+
             UI_BuildLabelF("blended world entities:        %F/%F", FmtUint(g->ss_blended->num_ents_allocated), FmtUint(g->ss_blended->num_ents_reserved));
             UI_BuildSeparator();
 
@@ -2105,9 +2107,7 @@ void UpdateUser(P_Window *window)
             draw_text(g->render_sig, D_TEXTPARAMS(.font = font, .pos = pos, .str = text, .offset_y = offset_y, .color = ColorWhite));
 #endif
         }
-        UI_PopSize(Axis_X);
-        UI_PopSize(Axis_Y);
-        UI_PopParent();
+        UI_PopCheckpoint();
     }
 #else
     if (g->debug_draw)
@@ -2545,7 +2545,6 @@ void UpdateUser(P_Window *window)
     }
 
     /* Render UI */
-    UI_PopParent();
     UI_SetDisplayImage(pp_root_box, g->ui_target);
     GPU_Resource *ui_render = UI_EndBuild(ui_viewport);
 
diff --git a/src/ui/ui.c b/src/ui/ui.c
index 6679bf63..08f336f8 100644
--- a/src/ui/ui.c
+++ b/src/ui/ui.c
@@ -3,118 +3,128 @@ UI_SharedState UI_shared_state = ZI;
 ////////////////////////////////
 //~ Key helpers
 
-UI_Key UI_KeyFromString(u64 seed, String str)
+u64 UI_HashFromTop(void)
+{
+    UI_Box *parent_box = UI_PeekTop(Parent);
+    u64 tag_hash = UI_PeekTop(Tag);
+    return RandU64FromSeeds(parent_box->key.hash, tag_hash);
+}
+
+u64 UI_HashFromString(u64 seed, String str)
 {
-    /* TOIMPL */
     if (seed == 0)
     {
-        UI_SharedState *g = &UI_shared_state;
-        seed = RandU64FromSeeds(g->top_parent->box->key.hash, g->top_tag->hash);
+        seed = UI_HashFromTop();
     }
+    return HashFnv64(seed, str);
+}
+
+UI_Key UI_KeyFromString(u64 seed, String str)
+{
     UI_Key result = ZI;
-    result.hash = HashFnv64(seed, str);
+    result.hash = UI_HashFromString(seed, str);
     return result;
 }
 
 ////////////////////////////////
-//~ Stack helpers
+//~ Checkpoint helpers
 
-//- Tag
-
-void UI_PushTagFromHash(u64 hash)
+void UI_PushCheckpoint(void)
 {
     UI_SharedState *g = &UI_shared_state;
-    if (g->top_tag)
+    UI_Checkpoint *cp = g->first_free_checkpoint;
+    if (cp)
     {
-        hash = RandU64FromSeeds(hash, g->top_tag->hash);
+        g->first_free_checkpoint = cp->next;
+        ZeroStruct(cp);
     }
-    UI_TagNode *n = PushStruct(g->build_arena, UI_TagNode);
-    StackPush(g->top_tag, n);
-    n->hash = hash;
-}
-
-void UI_PushTagFromString(String str)
-{
-    UI_SharedState *g = &UI_shared_state;
-    u64 hash = Fnv64Basis;
-    if (g->top_tag)
+    else
     {
-        hash = g->top_tag->hash;
+        cp = PushStruct(g->build_arena, UI_Checkpoint);
     }
-    hash = HashFnv64(hash, str);
-    UI_TagNode *n = PushStruct(g->build_arena, UI_TagNode);
-    n->hash = hash;
-    StackPush(g->top_tag, n);
+    cp->v = g->top_checkpoint->v + 1;
+    g->top_checkpoint = cp;
 }
 
-void UI_PushTagF_(char *fmt_cstr, ...)
+void UI_PopCheckpoint(void)
 {
-    TempArena scratch = BeginScratchNoConflict();
-    String str = ZI;
+    UI_SharedState *g = &UI_shared_state;
+    UI_Checkpoint *cp = g->top_checkpoint;
+    u64 v = cp->v;
+    for (UI_StyleKind kind = UI_StyleKind_None; kind < UI_StyleKind_Count; ++kind)
     {
-        va_list va;
-        va_start(va, fmt_cstr);
-        str = FormatStringV(scratch.arena, StringFromCstrNoLimit(fmt_cstr), va);
-        va_end(va);
+        UI_StyleNode *n = g->style_tops[kind];
+        while (n && n->checkpoint >= v)
+        {
+            UI_StyleNode *next = n->next;
+            g->style_tops[kind] = next;
+            n->next = g->first_free_style_node;
+            g->first_free_style_node = n;
+            n = next;
+        }
     }
-    UI_PushTagFromString(str);
-    EndScratch(scratch);
-}
-
-void UI_PopTag(void)
-{
-    StackPop(UI_shared_state.top_tag);
-}
-
-//- Parent
-
-void UI_PushParent(UI_Box *box)
-{
-    UI_SharedState *g = &UI_shared_state;
-    UI_ParentNode *n = PushStruct(g->build_arena, UI_ParentNode);
-    n->box = box;
-    StackPush(g->top_parent, n);
-}
-
-void UI_PopParent(void)
-{
-    StackPop(UI_shared_state.top_parent);
-}
-
-//- Size
-
-void UI_PushSize(Axis axis, UI_SizeKind kind, f32 v, f32 strictness)
-{
-    UI_SharedState *g = &UI_shared_state;
-    UI_SizeNode *n = PushStruct(g->build_arena, UI_SizeNode);
-    n->size.kind = kind;
-    n->size.v = v;
-    n->size.strictness = strictness;
-    StackPush(g->top_size[axis], n);
-}
-
-void UI_PopSize(Axis axis)
-{
-    StackPop(UI_shared_state.top_size[axis]);
-}
-
-//- Layout dir
-
-void UI_PushLayoutDir(Axis dir)
-{
-    UI_SharedState *g = &UI_shared_state;
-    UI_AxisNode *n = PushStruct(g->build_arena, UI_AxisNode);
-    n->axis = dir;
-    StackPush(g->top_layout_dir, n);
-}
-
-void UI_PopLayoutDir(void)
-{
-    StackPop(UI_shared_state.top_layout_dir);
+    cp->next = g->first_free_checkpoint;
+    g->first_free_checkpoint = cp;
 }
 
 ////////////////////////////////
-//~ Box helpers
+//~ Style stack helpers
+
+UI_StyleNode *UI_PushStyleNode(UI_StyleKind kind, b32 pop_when_touched, UI_Style desc)
+{
+    UI_SharedState *g = &UI_shared_state;
+    UI_StyleNode *n = g->first_free_style_node;
+    if (n)
+    {
+        g->first_free_style_node = n->next;
+        ZeroStruct(n);
+    }
+    else
+    {
+        n = PushStruct(g->build_arena, UI_StyleNode);
+    }
+    n->pop_when_touched = pop_when_touched;
+    n->style = desc;
+    n->next = g->style_tops[kind];
+    n->checkpoint = g->top_checkpoint->v;
+    g->style_tops[kind] = n;
+    return n;
+}
+
+UI_Style UI_PopStyleNode(UI_StyleKind kind)
+{
+    UI_SharedState *g = &UI_shared_state;
+    UI_StyleNode *n = g->style_tops[kind];
+    UI_Style style = n->style;
+    g->style_tops[kind] = n->next;
+    n->next = g->first_free_style_node;
+    g->first_free_style_node = n;
+    return style;
+}
+
+UI_StyleNode *UI_PeekStyleNode(UI_StyleKind kind)
+{
+    UI_SharedState *g = &UI_shared_state;
+    UI_StyleNode *n = g->style_tops[kind];
+    return n;
+}
+
+UI_Style UI_StyleFromTopNode(UI_StyleKind kind, b32 touch)
+{
+    UI_SharedState *g = &UI_shared_state;
+    UI_StyleNode *n = g->style_tops[kind];
+    UI_Style style = n->style;
+    if (touch && n->pop_when_touched)
+    {
+        g->style_tops[kind] = n->next;
+        n->next = g->first_free_style_node;
+        g->first_free_style_node = n;
+    }
+    return style;
+}
+
+////////////////////////////////
+//~ Box helper s
 
 UI_Box *UI_BuildBox(UI_Flag flags, UI_Key key)
 {
@@ -164,13 +174,13 @@ UI_Box *UI_BuildBox(UI_Flag flags, UI_Key key)
 
     box->tint = 0xFFFFFFFF;
 
-    /* Pull from stack */
-    box->parent = g->top_parent->box;
-    box->pref_size[Axis_X] = g->top_size[Axis_X]->size;
-    box->pref_size[Axis_Y] = g->top_size[Axis_Y]->size;
-    box->layout_dir = g->top_layout_dir->axis;
+    /* Pull from style stack */
+    box->parent             = UI_TouchTop(Parent);
+    box->pref_size[Axis_X]  = UI_TouchTop(Width);
+    box->pref_size[Axis_Y]  = UI_TouchTop(Height);
+    box->layout_axis        = UI_TouchTop(LayoutAxis);
 
-    DllPushBack(g->top_parent->box->first, g->top_parent->box->last, box);
+    DllPushBack(box->parent->first, box->parent->last, box);
     ++box->parent->count;
 
     return box;
@@ -212,6 +222,7 @@ void UI_BeginBuild(void)
     }
     ResetArena(g->build_arena);
     g->boxes_count = 0;
+    g->first_free_style_node = 0;
 
     /* Init bins */
     g->box_bins = PushStructs(g->build_arena, UI_BoxBin, UI_NumBoxLookupBins);
@@ -223,12 +234,28 @@ void UI_BeginBuild(void)
     DllPushBackNP(bin->first, bin->last, g->root_box, next_in_bin, prev_in_bin);
     ++g->boxes_count;
 
-    /* Init stacks */
-    UI_PushTagF("root");
-    UI_PushParent(g->root_box);
-    UI_PushSize(Axis_X, UI_SizeKind_Percent, 1, 0);
-    UI_PushSize(Axis_Y, UI_SizeKind_Percent, 1, 0);
-    UI_PushLayoutDir(Axis_X);
+    /* Init checkpoints */
+    g->top_checkpoint = PushStruct(g->build_arena, UI_Checkpoint);
+
+    /* Init styles */
+    {
+        UI_StyleNode *nodes = PushStructs(g->build_arena, UI_StyleNode, UI_StyleKind_Count);
+        for (UI_StyleKind kind = UI_StyleKind_None; kind < UI_StyleKind_Count; ++kind)
+        {
+            UI_StyleNode *n = &nodes[kind];
+            UI_Style *style = &n->style;
+            style->kind = kind;
+            g->style_tops[kind] = n;
+            switch(kind)
+            {
+                default: break;
+                case UI_StyleKind_Tag:      { style->Tag    = HashFnv64(Fnv64Basis, Lit("root")); } break;
+                case UI_StyleKind_Parent:   { style->Parent = g->root_box;                        } break;
+                case UI_StyleKind_Width:    { style->Width  = UI_RatioSize(1, 0);                 } break;
+                case UI_StyleKind_Height:   { style->Height = UI_RatioSize(1, 0);                 } break;
+            }
+        }
+    }
 
     if (!g->back_build_arena)
     {
@@ -323,7 +350,7 @@ GPU_Resource *UI_EndBuild(Rect render_viewport)
         for (Axis axis = 0; axis < Axis_CountXY; ++axis)
         {
             UI_Size pref_size = box->pref_size[axis];
-            if (pref_size.kind == UI_SizeKind_Percent)
+            if (pref_size.kind == UI_SizeKind_Ratio)
             {
                 UI_Box *ancestor = box->parent;
                 f32 ancestor_size = 0;
@@ -349,7 +376,7 @@ GPU_Resource *UI_EndBuild(Rect render_viewport)
         Vec2 final_size = VEC2(box->solved_dims[0], box->solved_dims[1]);
         if (parent)
         {
-            b32 is_layout_x = parent->layout_dir == Axis_X;
+            b32 is_layout_x = parent->layout_axis == Axis_X;
             f32 layout_cursor = parent->layout_cursor;
             Vec2 offset = VEC2(layout_cursor * is_layout_x, layout_cursor * !is_layout_x);
             parent->layout_cursor += final_size.x * is_layout_x + final_size.y * is_layout_x;
diff --git a/src/ui/ui.h b/src/ui/ui.h
index c14db5ef..076a8427 100644
--- a/src/ui/ui.h
+++ b/src/ui/ui.h
@@ -15,7 +15,7 @@ Struct(UI_Key)
 Enum(UI_SizeKind)
 {
     UI_SizeKind_Children,
-    UI_SizeKind_Percent,
+    UI_SizeKind_Ratio,
     UI_SizeKind_Pixel,
     UI_SizeKind_Text,
 };
@@ -52,7 +52,7 @@ Struct(UI_Box)
     String display_text;
     GPU_Resource *display_image;
     UI_Size pref_size[Axis_CountXY];
-    Axis layout_dir;
+    Axis layout_axis;
     u32 tint;
 
     //- Layout data
@@ -71,12 +71,56 @@ Struct(UI_BoxBin)
 };
 
 ////////////////////////////////
-//~ Stack types
+//~ Style types
 
-Struct(UI_TagNode) { UI_TagNode *next; u64 hash; };
-Struct(UI_ParentNode) { UI_ParentNode *next; UI_Box *box; };
-Struct(UI_SizeNode) { UI_SizeNode *next; UI_Size size; };
-Struct(UI_AxisNode) { UI_AxisNode *next; Axis axis; };
+//- Style data
+#define UI_StyleKindsXMacro(x)    \
+    x(Tag,             u64)       \
+    x(Parent,          UI_Box *)  \
+    x(LayoutAxis,      Axis)      \
+    x(Width,           UI_Size)   \
+    x(Height,          UI_Size)   \
+    x(BackgroundColor, u32)       \
+    x(Opacity,         f32)       \
+
+//- Style node
+Enum(UI_StyleKind)
+{
+    #define X(name, type) UI_StyleKind_##name,
+        UI_StyleKind_None,
+        UI_StyleKindsXMacro(X)
+        UI_StyleKind_Count,
+    #undef X
+};
+
+Struct(UI_Style)
+{
+    UI_StyleKind kind;
+    /* Union of all style data types */
+    union
+    {
+        #define X(name, type) type name;
+            UI_StyleKindsXMacro(X)
+        #undef X
+    };
+};
+
+Struct(UI_StyleNode)
+{
+    UI_StyleNode *next;
+    b32 pop_when_touched;
+    u64 checkpoint;
+    UI_Style style;
+};
+
+////////////////////////////////
+//~ Checkpoint types
+
+Struct(UI_Checkpoint)
+{
+    UI_Checkpoint *next;
+    u64 v;
+};
 
 ////////////////////////////////
 //~ State types
@@ -98,17 +142,16 @@ Struct(UI_SharedState)
     u64 boxes_count;
     u64 back_boxes_count;
 
-    //- Stack state
-    UI_TagNode *top_tag;
-    UI_ParentNode *top_parent;
-    UI_SizeNode *top_size[Axis_CountXY];
-    UI_AxisNode *top_layout_dir;
+    UI_Checkpoint *top_checkpoint;
+    UI_Checkpoint *first_free_checkpoint;
+
+    UI_StyleNode *style_tops[UI_StyleKind_Count];
+    UI_StyleNode *first_free_style_node;
 
     //- Render state
     GPU_Resource *render_target;
     i64 render_fence_target;
 
-
     GPU_TransientBuffer draw_rects_tbuff;
     Arena *draw_rects_arena;
 
@@ -117,29 +160,37 @@ Struct(UI_SharedState)
 ////////////////////////////////
 //~ Key helpers
 
+u64 UI_HashFromTop(void);
+u64 UI_HashFromString(u64 seed, String str);
 UI_Key UI_KeyFromString(u64 seed, String str);
 
 ////////////////////////////////
-//~ Stack helpers
+//~ Checkpoint helpers
 
-//- Tag
-void UI_PushTagFromHash(u64 hash);
-void UI_PushTagFromString(String str);
-#define UI_PushTagF(fmt_cstr, ...) UI_PushTagF_(fmt_cstr, __VA_ARGS__, FmtEnd);
-void UI_PushTagF_(char *fmt_cstr, ...);
-void UI_PopTag(void);
+void UI_PushCheckpoint(void);
+void UI_PopCheckpoint(void);
 
-//- Parent
-void UI_PushParent(UI_Box *box);
-void UI_PopParent(void);
+////////////////////////////////
+//~ Style stack helpers
 
-//- Size
-void UI_PushSize(Axis axis, UI_SizeKind kind, f32 v, f32 strictness);
-void UI_PopSize(Axis axis);
+UI_StyleNode *UI_PushStyleNode(UI_StyleKind kind, b32 pop_when_touched, UI_Style desc);
+UI_Style UI_PopStyleNode(UI_StyleKind kind);
+UI_StyleNode *UI_PeekTopStyleNode(UI_StyleKind kind);
+UI_Style UI_StyleFromTopNode(UI_StyleKind kind, b32 touch);
 
-//- Layout dir
-void UI_PushLayoutDir(Axis dir);
-void UI_PopLayoutDir(void);
+#define UI_SetNext(name, ...)    UI_PushStyleNode(UI_StyleKind_##name, 1, (UI_Style) { .name = __VA_ARGS__ })
+#define UI_Push(name, ...)       UI_PushStyleNode(UI_StyleKind_##name, 0, (UI_Style) { .name = __VA_ARGS__ })
+#define UI_Pop(name, ...)        UI_PopStyleNode(UI_StyleKind_##name).name
+#define UI_TouchTop(name)        UI_StyleFromTopNode(UI_StyleKind_##name, 1).name
+#define UI_PeekTop(name)         UI_StyleFromTopNode(UI_StyleKind_##name, 0).name
+
+////////////////////////////////
+//~ Size helpers
+
+#define UI_ChildrenSize(_strictness)             ((UI_Size) { .kind = UI_SizeKind_Children, .strictness = strictness_ })
+#define UI_RatioSize(_ratio, _strictness)        ((UI_Size) { .kind = UI_SizeKind_Ratio, .v = _ratio, .strictness = _strictness })
+#define UI_PixelSize(_pixels, _strictness)       ((UI_Size) { .kind = UI_SizeKind_Pixel, .v = _pixels, .strictness = _strictness })
+#define UI_TextSize(_strictness)                 ((UI_Size) { .kind = UI_SizeKind_Text, .strictness = _strictness })
 
 ////////////////////////////////
 //~ Box