diff --git a/src/musicplayer/ui/layout.gleam b/src/musicplayer/ui/layout.gleam
index 0b83862..c7b9993 100644
--- a/src/musicplayer/ui/layout.gleam
+++ b/src/musicplayer/ui/layout.gleam
@@ -18,8 +18,13 @@ pub type Section {
   PlaybackTime
 }
 
+pub type Dimension {
+  Percent(width: Int, height: Int)
+  Flex
+}
+
 pub type Style {
-  Style(width_percent: Int, height_percent: Int)
+  Style(dimensions: Dimension)
 }
 
 /// A Nodes width and height is in percentage (of the available width/height of its parent Node)
@@ -28,6 +33,7 @@ pub type Node {
   Cell(content: String, style: Style)
 }
 
+/// The root node must use `Root` section
 pub type Layout {
   Layout(width: Int, height: Int, nodes: dict.Dict(Section, Node))
 }
@@ -39,7 +45,7 @@ pub fn new() -> Layout {
         Root,
         Row(
           content: "Music Player",
-          style: Style(width_percent: 100, height_percent: 100),
+          style: Style(dimensions: Percent(width: 100, height: 100)),
           children: [Header, Search, PlaybackTime],
         ),
       ),
@@ -47,7 +53,7 @@ pub fn new() -> Layout {
         Header,
         Row(
           content: "Foo (1) | Bar (2) | Baz (3)",
-          style: Style(width_percent: 100, height_percent: 33),
+          style: Style(dimensions: Percent(width: 100, height: 33)),
           children: [],
         ),
       ),
@@ -55,7 +61,7 @@ pub fn new() -> Layout {
         Search,
         Row(
           content: "",
-          style: Style(width_percent: 100, height_percent: 33),
+          style: Style(dimensions: Percent(width: 100, height: 33)),
           children: [],
         ),
       ),
@@ -63,7 +69,7 @@ pub fn new() -> Layout {
         PlaybackTime,
         Row(
           content: "00:00",
-          style: Style(width_percent: 100, height_percent: 33),
+          style: Style(dimensions: Percent(width: 100, height: 33)),
           children: [],
         ),
       ),
@@ -95,6 +101,7 @@ pub fn update_dimensions(layout: Layout, width: Int, height: Int) -> Layout {
 
 pub fn render(layout: Layout) -> Nil {
   internal.clear_screen()
+
   [layout.width, layout.height]
   |> list.map(int.to_string)
   |> string.join(" ")
@@ -157,15 +164,22 @@ pub fn render_generic(
     Ok(node) -> {
       let margin = 2.0
 
-      let width =
-        container_width *. { int.to_float(node.style.width_percent) /. 100.0 }
-        |> float.floor
-        |> float.truncate
+      let #(width, height) = case node.style.dimensions {
+        Flex -> todo
+        Percent(width:, height:) -> {
+          let width =
+            container_width *. { int.to_float(width) /. 100.0 }
+            |> float.floor
+            |> float.truncate
 
-      let height =
-        container_height *. { int.to_float(node.style.height_percent) /. 100.0 }
-        |> float.floor
-        |> float.truncate
+          let height =
+            container_height *. { int.to_float(height) /. 100.0 }
+            |> float.floor
+            |> float.truncate
+
+          #(width, height)
+        }
+      }
 
       let #(cx, cy) = case node {
         Row(..) -> #(container_tl_x, container_tl_y + { index * height })
@@ -185,25 +199,30 @@ pub fn render_generic(
           |> list.fold(parent, fn(acc_into, ic) {
             let #(i, child) = ic
 
-            let cw =
-              container_width
-              *. { int.to_float(node.style.width_percent) /. 100.0 }
-              -. margin
-              |> float.floor
+            let #(width, height) = case node.style.dimensions {
+              Flex -> todo
+              Percent(width:, height:) -> {
+                let width =
+                  container_width *. { int.to_float(width) /. 100.0 } -. margin
+                  |> float.floor
 
-            let ch =
-              container_height
-              *. { int.to_float(node.style.height_percent) /. 100.0 }
-              -. margin
-              |> float.floor
+                let height =
+                  container_height
+                  *. { int.to_float(height) /. 100.0 }
+                  -. margin
+                  |> float.floor
+
+                #(width, height)
+              }
+            }
 
             let child_origin_x = container_tl_x + 1
             let child_origin_y = container_tl_y + 1
 
             render_generic(
               layout,
-              cw,
-              ch,
+              width,
+              height,
               child_origin_x,
               child_origin_y,
               i,
diff --git a/src/musicplayer/ui/layout_examples/layout_examples.gleam b/src/musicplayer/ui/layout_examples/layout_examples.gleam
index 6c93217..d231a79 100644
--- a/src/musicplayer/ui/layout_examples/layout_examples.gleam
+++ b/src/musicplayer/ui/layout_examples/layout_examples.gleam
@@ -1,7 +1,7 @@
 import gleam/dict
 
 import musicplayer/ui/internal
-import musicplayer/ui/layout.{Layout, Section, Style}
+import musicplayer/ui/layout.{Layout, Percent, Section, Style}
 import musicplayer/ui/layout_examples/wait_for_input.{wait_for_input}
 
 pub fn main() {
@@ -21,10 +21,10 @@ fn two_rows_with_cells(width: Int, height: Int) -> layout.Layout {
   let nodes =
     dict.from_list([
       #(
-        Section("Root"),
+        layout.Root,
         layout.Row(
           content: "container",
-          style: Style(width_percent: 100, height_percent: 100),
+          style: Style(dimensions: Percent(width: 100, height: 100)),
           children: [
             Section("Row1"),
             Section("Row2"),
@@ -35,7 +35,7 @@ fn two_rows_with_cells(width: Int, height: Int) -> layout.Layout {
         Section("Row1"),
         layout.Row(
           content: "row 1",
-          style: Style(width_percent: 100, height_percent: 50),
+          style: Style(dimensions: Percent(width: 100, height: 50)),
           children: [
             Section("A"),
             Section("A"),
@@ -46,21 +46,21 @@ fn two_rows_with_cells(width: Int, height: Int) -> layout.Layout {
         Section("A"),
         layout.Cell(
           content: "cell 1",
-          style: Style(width_percent: 50, height_percent: 100),
+          style: Style(dimensions: Percent(width: 50, height: 50)),
         ),
       ),
       #(
         Section("B"),
         layout.Cell(
           content: "cell 2",
-          style: Style(width_percent: 50, height_percent: 100),
+          style: Style(dimensions: Percent(width: 50, height: 50)),
         ),
       ),
       #(
         Section("Row2"),
         layout.Row(
           content: "row 2",
-          style: Style(width_percent: 100, height_percent: 50),
+          style: Style(dimensions: Percent(width: 50, height: 50)),
           children: [],
         ),
       ),
diff --git a/test/musicplayer/ui/layout_test.gleam b/test/musicplayer/ui/layout_test.gleam
index 433c751..15c8472 100644
--- a/test/musicplayer/ui/layout_test.gleam
+++ b/test/musicplayer/ui/layout_test.gleam
@@ -5,23 +5,23 @@ import gleeunit
 import gleeunit/should
 import musicplayer/ui/virtual_ansi
 
-import musicplayer/ui/layout.{Layout, Section, Style}
+import musicplayer/ui/layout.{Layout, Percent, Section, Style}
 
 pub fn main() -> Nil {
   gleeunit.main()
 }
 
-pub fn foo_test() {
+pub fn percent_layout_test() {
   let layout =
     Layout(
       width: 80,
       height: 20,
       nodes: dict.from_list([
         #(
-          Section("Root"),
+          layout.Root,
           layout.Row(
             content: "container",
-            style: Style(width_percent: 100, height_percent: 100),
+            style: Style(dimensions: Percent(width: 100, height: 100)),
             children: [
               Section("Row1"),
               Section("Row2"),
@@ -32,7 +32,7 @@ pub fn foo_test() {
           Section("Row1"),
           layout.Row(
             content: "row 1",
-            style: Style(width_percent: 100, height_percent: 50),
+            style: Style(dimensions: Percent(width: 100, height: 50)),
             children: [
               Section("A"),
               Section("B"),
@@ -43,21 +43,21 @@ pub fn foo_test() {
           Section("A"),
           layout.Cell(
             content: "cell 1",
-            style: Style(width_percent: 50, height_percent: 100),
+            style: Style(dimensions: Percent(width: 50, height: 100)),
           ),
         ),
         #(
           Section("B"),
           layout.Cell(
             content: "cell 2",
-            style: Style(width_percent: 50, height_percent: 100),
+            style: Style(dimensions: Percent(width: 50, height: 100)),
           ),
         ),
         #(
           Section("Row2"),
           layout.Row(
             content: "row 1",
-            style: Style(width_percent: 100, height_percent: 50),
+            style: Style(dimensions: Percent(width: 100, height: 50)),
             children: [],
           ),
         ),
@@ -88,8 +88,7 @@ container───────────────────────
 └──────────────────────────────────────────────────────────────────────────────┘
 "
 
-  let visual =
-    virtual_ansi.render(layout, Section("Root"), layout.width, layout.height)
+  let visual = virtual_ansi.render(layout)
   case visual == string.trim(expected) {
     True -> Nil
     False -> {
diff --git a/test/musicplayer/ui/virtual_ansi.gleam b/test/musicplayer/ui/virtual_ansi.gleam
index ad8c692..525ee2a 100644
--- a/test/musicplayer/ui/virtual_ansi.gleam
+++ b/test/musicplayer/ui/virtual_ansi.gleam
@@ -3,12 +3,12 @@ import gleam/int
 import gleam/list
 import gleam/string
 
-import musicplayer/ui/layout.{type Layout, type Section, Renders}
+import musicplayer/ui/layout.{type Layout, Renders}
 
 pub type Screen =
   dict.Dict(#(Int, Int), String)
 
-pub fn render(layout: Layout, root: Section, width: Int, height: Int) -> String {
+pub fn render(layout: Layout) -> String {
   let test_renders =
     Renders(
       box: fn(screen, x, y, w, h) { box(screen, x, y, w, h) },
@@ -18,12 +18,12 @@ pub fn render(layout: Layout, root: Section, width: Int, height: Int) -> String
   let screen =
     layout.render_generic(
       layout,
-      int.to_float(width),
-      int.to_float(height),
+      int.to_float(layout.width),
+      int.to_float(layout.height),
       1,
       1,
       0,
-      root,
+      layout.Root,
       dict.new(),
       test_renders,
     )