diff --git a/assets/AdwaitaSans-Regular.ttf b/assets/AdwaitaSans-Regular.ttf
new file mode 100644
index 0000000..6fcafd9
Binary files /dev/null and b/assets/AdwaitaSans-Regular.ttf differ
diff --git a/src/application.cpp b/src/application.cpp
new file mode 100644
index 0000000..5db71e2
--- /dev/null
+++ b/src/application.cpp
@@ -0,0 +1,81 @@
+#include "application.h"
+#include "style.h"
+#include "elements.h"
+#include "simulation.h"
+#include <SDL3/SDL.h>
+#include <clay/clay.h>
+
+namespace application {
+namespace internal {
+bool isSimulating{ false };
+}
+
+static void SetSimulatingButton(Clay_ElementId element, Clay_PointerData pointer, intptr_t data) {
+	if (pointer.state == CLAY_POINTER_DATA_PRESSED_THIS_FRAME) {
+		internal::isSimulating = data == 1;
+	}
+}
+
+static void RandomizeFieldButton(Clay_ElementId element, Clay_PointerData pointer, intptr_t data) {
+	if (pointer.state == CLAY_POINTER_DATA_PRESSED_THIS_FRAME) {
+		simulation::InitializeRandom(2, 300);
+	}
+}
+
+static void StepSimulationButton(Clay_ElementId element, Clay_PointerData pointer, intptr_t data) {
+	if (pointer.state == CLAY_POINTER_DATA_PRESSED_THIS_FRAME) {
+		simulation::Step();
+	}
+}
+
+static void StepControl() {
+	CLAY_AUTO_ID({
+		.layout = {
+			.childGap = 16
+		}
+	}) {
+		if (internal::isSimulating) {
+			elements::TextButton(CLAY_STRING("Pause"), style::warningButton, &SetSimulatingButton, false);
+		} else {
+			elements::TextButton(CLAY_STRING("Start"), style::proceedButton, &SetSimulatingButton, true);
+			elements::TextButton(CLAY_STRING("Step"), style::actionButton, &StepSimulationButton);
+		}
+	}
+}
+
+static void PrimaryControls() {
+	static bool isOpen{ true };
+	if (isOpen) {
+		CLAY_AUTO_ID(style::LeftPanelContainer(0, {
+			.layout = {
+				.sizing = { CLAY_SIZING_FIT(.18) },
+			}
+		})) {
+			CLAY_AUTO_ID({
+				.layout = {
+					.childGap = 16,
+					.layoutDirection = CLAY_TOP_TO_BOTTOM,
+				},
+				.clip = {
+					true, true, Clay_GetScrollOffset()
+				}
+			}) {
+				StepControl();
+				elements::TextButton(CLAY_STRING("Randomize"), style::actionButton, &RandomizeFieldButton);
+			}
+		}
+	}
+}
+
+Clay_RenderCommandArray RenderApplication() {
+	Clay_BeginLayout();
+	CLAY(CLAY_ID("OuterContainer"), style::Window()) {
+		simulation::SetSimulationHovered(Clay_Hovered());
+		PrimaryControls();
+	}
+	return Clay_EndLayout();
+}
+
+void HandleEvent(SDL_Event event) {
+}
+}
diff --git a/src/application.h b/src/application.h
new file mode 100644
index 0000000..9d74ea0
--- /dev/null
+++ b/src/application.h
@@ -0,0 +1,12 @@
+#ifndef APPLICATION_H
+#define APPLICATION_H
+
+#include <clay/clay.h>
+#include <SDL3/SDL_events.h>
+
+namespace application {
+Clay_RenderCommandArray RenderApplication();
+void HandleEvent(SDL_Event event);
+}
+
+#endif // !APPLICATION_H
diff --git a/src/elements.cpp b/src/elements.cpp
new file mode 100644
index 0000000..32a96f1
--- /dev/null
+++ b/src/elements.cpp
@@ -0,0 +1,36 @@
+#include "elements.h"
+#include "style.h"
+#include "resources.h"
+
+namespace elements {
+void TextButton(Clay_String text, Clay_Color color, OnHoveredFn onHovered, intptr_t onHoveredData) {
+	Clay_Color hovered{ style::ToHoveredColor(color) };
+	CLAY_AUTO_ID({
+		.layout = {
+			.padding = style::buttonPadding,
+			.childAlignment = { CLAY_ALIGN_X_CENTER, CLAY_ALIGN_Y_CENTER },
+		},
+		.backgroundColor = Clay_Hovered() ? hovered : color,
+		.cornerRadius = style::buttonRadii,
+		.border = { style::ToHoveredColor(Clay_Hovered() ? hovered : color), CLAY_BORDER_ALL(1) },
+	}) {
+		elements::Body(text, {
+			.textColor = style::TextColors(0),
+			.textAlignment = CLAY_TEXT_ALIGN_CENTER,
+		});
+		Clay_OnHover(onHovered, onHoveredData);
+	}
+}
+
+void Body(Clay_String string, Clay_TextElementConfig baseCfg) {
+	baseCfg.fontId = resources::FONT_DEFAULT;
+	baseCfg.fontSize = style::baseFontSize;
+	CLAY_TEXT(string, CLAY_TEXT_CONFIG(baseCfg));
+}
+
+void Header(Clay_String string, size_t header, Clay_TextElementConfig baseCfg) {
+	baseCfg.fontId = resources::FONT_BOLD;
+	baseCfg.fontSize = style::headerSizes[(header)-1];
+	CLAY_TEXT(string, CLAY_TEXT_CONFIG(baseCfg));
+}
+}
diff --git a/src/elements.h b/src/elements.h
new file mode 100644
index 0000000..fb1c1e9
--- /dev/null
+++ b/src/elements.h
@@ -0,0 +1,14 @@
+#ifndef ELEMENTS_H
+#define ELEMENTS_H
+
+#include <clay/clay.h>
+
+namespace elements {
+typedef void(*OnHoveredFn)(Clay_ElementId element, Clay_PointerData pointer, intptr_t data);
+
+void TextButton(Clay_String text, Clay_Color color, OnHoveredFn onHovered, intptr_t onHoveredData = 0);
+void Body(Clay_String string, Clay_TextElementConfig baseCfg);
+void Header(Clay_String string, size_t header, Clay_TextElementConfig baseCfg);
+}
+
+#endif // !ELEMENTS_H
diff --git a/src/input.cpp b/src/input.cpp
new file mode 100644
index 0000000..b6bb773
--- /dev/null
+++ b/src/input.cpp
@@ -0,0 +1,39 @@
+#include "input.h"
+
+namespace input {
+Clay_Vector2 scrollMotion{ 0, 0 };
+bool shiftDown{ false };
+bool mouseButtonDown{ false };
+
+void FrameStart() {
+	scrollMotion = { 0, 0 };
+}
+
+void HandleEvent(SDL_Event const &event) {
+	switch (event.type) {
+		case SDL_EVENT_MOUSE_WHEEL:
+			if (shiftDown) {
+				scrollMotion = (Clay_Vector2) { event.wheel.y * 2.f, -event.wheel.x * 5.f };
+			} else {
+				scrollMotion = (Clay_Vector2) { -event.wheel.x * 2.f, event.wheel.y * 5.f };
+			}
+			break;
+		case SDL_EVENT_MOUSE_MOTION:
+			Clay_SetPointerState((Clay_Vector2) { event.motion.x, event.motion.y }, mouseButtonDown);
+			break;
+		case SDL_EVENT_MOUSE_BUTTON_DOWN:
+		case SDL_EVENT_MOUSE_BUTTON_UP:
+			if (event.button.button == SDL_BUTTON_LEFT) {
+				mouseButtonDown = event.button.down;
+				Clay_SetPointerState((Clay_Vector2) { event.button.x, event.button.y }, mouseButtonDown);
+			}
+			break;
+		case SDL_EVENT_KEY_DOWN:
+		case SDL_EVENT_KEY_UP:
+			if (event.key.key == SDLK_LSHIFT || event.key.key == SDLK_RSHIFT) {
+				shiftDown = event.key.down;
+			}
+			break;
+	}
+}
+}
diff --git a/src/input.h b/src/input.h
new file mode 100644
index 0000000..ddd2c09
--- /dev/null
+++ b/src/input.h
@@ -0,0 +1,15 @@
+#ifndef INPUT_H
+#define INPUT_H
+
+#include <SDL3/SDL_events.h>
+#include <clay/clay.h>
+
+namespace input {
+extern Clay_Vector2 scrollMotion;
+extern bool shiftDown;
+extern bool mouseButtonDown;
+void FrameStart();
+void HandleEvent(SDL_Event const &event);
+}
+
+#endif // !INPUT_H
diff --git a/src/main.cpp b/src/main.cpp
new file mode 100644
index 0000000..8d0d60a
--- /dev/null
+++ b/src/main.cpp
@@ -0,0 +1,146 @@
+#define SDL_MAIN_HANDLED
+
+#include "application.h"
+#include "input.h"
+#include "resources.h"
+#include "simulation.h"
+#include <SDL3/SDL.h>
+#include <SDL3/SDL_error.h>
+#include <SDL3/SDL_events.h>
+#include <SDL3/SDL_hints.h>
+#include <SDL3/SDL_init.h>
+#include <SDL3/SDL_keycode.h>
+#include <SDL3/SDL_log.h>
+#include <SDL3/SDL_mouse.h>
+#include <SDL3/SDL_render.h>
+#include <SDL3/SDL_video.h>
+#include <SDL3_ttf/SDL_ttf.h>
+#include <clay/clay.h>
+#include <renderer/clay_renderer_SDL3.h>
+#include <renderer/ui_data.h>
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <stdlib.h>
+
+constexpr SDL_InitFlags sdlInitFlags = SDL_WINDOW_RESIZABLE | SDL_WINDOW_HIGH_PIXEL_DENSITY;
+
+SDL_Window *window = nullptr;
+SDL_Renderer *renderer = nullptr;
+int screenWidth = 1920, screenHeight = 1080;
+bool running = true;
+uint64_t clayMemorySize = 0;
+
+Clay_Arena clayPrimaryArena;
+
+Clay_SDL3RendererData backendData = {
+	nullptr, nullptr, nullptr
+};
+
+static
+Clay_Dimensions MeasureText(Clay_StringSlice text, Clay_TextElementConfig *config, void *userData) {
+	TTF_Font **fonts = (TTF_Font**)userData;
+	TTF_Font *font = fonts[config->fontId];
+	int width, height;
+	TTF_SetFontSize(font, config->fontSize);
+	if (!TTF_GetStringSize(font, text.chars, text.length, &width, &height)) {
+		SDL_LogError(SDL_LOG_CATEGORY_ERROR, "MeasureText failed to measure text %s", SDL_GetError());
+	}
+	return (Clay_Dimensions) { (float)width, (float)height };
+}
+
+static
+void HandleClayErrors(Clay_ErrorData data) {
+	SDL_LogError(SDL_LOG_CATEGORY_ERROR, "%s", data.errorText.chars);
+}
+
+static inline
+void LogOutputResolution() {
+	int w, h;
+	SDL_GetCurrentRenderOutputSize(renderer, &w, &h);
+	SDL_Log("output size: %i, %d", w, h);
+}
+
+static inline
+void InitSDL() {
+	SDL_SetHint(SDL_HINT_RENDER_LINE_METHOD, "3");
+	if (!SDL_Init(SDL_INIT_VIDEO | SDL_INIT_EVENTS)) {
+		SDL_LogError(SDL_LOG_CATEGORY_ERROR, "SDL_Init failed: %s", SDL_GetError());
+		exit(1);
+	}
+	if ((window = SDL_CreateWindow("Window", screenWidth, screenHeight, sdlInitFlags)) == nullptr) {
+		SDL_LogError(SDL_LOG_CATEGORY_ERROR, "SDL_CreateWindow failed: %s", SDL_GetError());
+		exit(2);
+	}
+	if ((renderer = SDL_CreateRenderer(window, NULL)) == nullptr) {
+		SDL_LogError(SDL_LOG_CATEGORY_ERROR, "SDL_CreateRenderer failed: %s", SDL_GetError());
+		exit(3);
+	}
+	if (!TTF_Init()) {
+		SDL_LogError(SDL_LOG_CATEGORY_ERROR, "TTF_Init failed: %s", SDL_GetError());
+		exit(4);
+	}
+	if ((resources::textEngine = TTF_CreateRendererTextEngine(renderer)) == nullptr) {
+		SDL_LogError(SDL_LOG_CATEGORY_ERROR, "TTF_CreateRendererTextEngine failed: %s", SDL_GetError());
+		exit(5);
+	}
+}
+
+static
+void InitClay() {
+	clayMemorySize = Clay_MinMemorySize();
+	clayPrimaryArena = Clay_CreateArenaWithCapacityAndMemory(clayMemorySize, SDL_malloc(clayMemorySize));
+	Clay_Initialize(clayPrimaryArena, { (float)screenWidth, (float)screenHeight }, { HandleClayErrors });
+	Clay_SetMeasureTextFunction(MeasureText, resources::fonts);
+	Clay_SetLayoutDimensions({ (float)screenWidth, (float)screenHeight });
+	float x, y;
+	SDL_GetMouseState(&x, &y);
+	Clay_SetPointerState((Clay_Vector2) { x, y }, false);
+}
+
+int main(int argc, char *argv[]) {
+	InitSDL();
+	resources::LoadResources();
+	LogOutputResolution();
+	InitClay();
+	backendData = (Clay_SDL3RendererData) { renderer, resources::textEngine, resources::fonts };
+	SDL_Event event;
+	uint64_t startFrameTime = SDL_GetTicksNS();
+	double deltaTime = 0.0;
+	while (running) {
+		std::srand(SDL_GetTicksNS());
+		deltaTime = SDL_GetTicksNS() - startFrameTime;
+		startFrameTime = SDL_GetTicksNS();
+		UiData_Clear();
+		input::FrameStart();
+		while (SDL_PollEvent(&event)) {
+			application::HandleEvent(event);
+			input::HandleEvent(event);
+			switch (event.type) {
+				case SDL_EVENT_QUIT:
+					running = false;
+					break;
+				case SDL_EVENT_WINDOW_RESIZED:
+					Clay_SetLayoutDimensions({
+						(float)event.window.data1,
+						(float)event.window.data2
+					});
+					LogOutputResolution();
+					break;
+				default: break;
+			}
+		}
+		Clay_UpdateScrollContainers(true, input::scrollMotion, deltaTime);
+		SDL_SetRenderDrawColor(renderer, 0, 0, 0, 255);
+		SDL_RenderClear(renderer);
+		simulation::Draw(renderer, 0.01);
+		Clay_RenderCommandArray commands{ application::RenderApplication() };
+		SDL_Clay_RenderClayCommands(&backendData, &commands);
+		SDL_RenderPresent(renderer);
+		SDL_Delay(10);
+	}
+	SDL_DestroyRenderer(renderer);
+	SDL_DestroyWindow(window);
+	SDL_Quit();
+	return 0;
+}
diff --git a/src/resources.cpp b/src/resources.cpp
new file mode 100644
index 0000000..845ef9f
--- /dev/null
+++ b/src/resources.cpp
@@ -0,0 +1,32 @@
+#include "resources.h"
+#include "style.h"
+#include <clay/clay.h>
+#include <SDL3/SDL_log.h>
+#include <SDL3/SDL_render.h>
+#include <SDL3_image/SDL_image.h>
+
+namespace resources {
+TTF_Font *fonts[FONT_MAX];
+TTF_TextEngine *textEngine = nullptr;
+
+static inline void LoadFonts() {
+	fonts[FONT_DEFAULT] = TTF_OpenFont("assets/AdwaitaSans-Regular.ttf", style::baseFontSize * 5);
+	if (fonts[FONT_DEFAULT] == nullptr) {
+		SDL_LogError(SDL_LOG_CATEGORY_ERROR, "TTF_OpenFont failed: Failed to load adwaita sans: %s", SDL_GetError());
+		exit(6);
+	}
+	TTF_SetFontHinting(fonts[FONT_DEFAULT], TTF_HINTING_LIGHT_SUBPIXEL);
+	fonts[FONT_BOLD] = TTF_OpenFont("assets/AdwaitaSans-Regular.ttf", style::baseFontSize * 5);
+	if (fonts[FONT_BOLD] == nullptr) {
+		SDL_LogError(SDL_LOG_CATEGORY_ERROR, "TTF_OpenFont failed: Failed to load adwaita sans bold: %s", SDL_GetError());
+		exit(6);
+	}
+	TTF_SetFontHinting(fonts[FONT_BOLD], TTF_HINTING_LIGHT_SUBPIXEL);
+	TTF_SetFontStyle(fonts[FONT_BOLD], TTF_STYLE_BOLD);
+	SDL_Log("LoadFonts: Success");
+}
+
+void LoadResources() {
+	LoadFonts();
+}
+}
diff --git a/src/resources.h b/src/resources.h
new file mode 100644
index 0000000..ef12346
--- /dev/null
+++ b/src/resources.h
@@ -0,0 +1,19 @@
+#ifndef RESOURCES_H
+#define RESOURCES_H
+
+#include <SDL3_ttf/SDL_ttf.h>
+
+namespace resources {
+enum Font {
+	FONT_DEFAULT = 0,
+	FONT_BOLD = 1,
+	FONT_MAX
+};
+
+extern TTF_TextEngine *textEngine;
+extern TTF_Font *fonts[FONT_MAX];
+
+void LoadResources();
+}
+
+#endif // !RESOURCES_H
diff --git a/src/simulation.cpp b/src/simulation.cpp
new file mode 100644
index 0000000..0b97b33
--- /dev/null
+++ b/src/simulation.cpp
@@ -0,0 +1,192 @@
+#include "simulation.h"
+#include "input.h"
+#include <cstdint>
+#include <ranges>
+#include <random>
+#include <algorithm>
+#include <clay/clay.h>
+#include <SDL3/SDL_log.h>
+#include <SDL3/SDL_render.h>
+
+namespace simulation {
+std::set<Cell> living{};
+static std::vector<Cell> overpopulated{};
+static std::vector<Cell> underpopulated{};
+static std::vector<Cell> born{};
+
+#ifdef __glibc_likely
+#define likely(cond_) __glibc_likely(cond_)
+#else
+#define likely(cond_) (cond_)
+#endif
+
+CellIterator::CellIterator(Cell begin, Cell end)
+: state{ begin } , begin{ begin }, end{ end } {}
+
+CellIterator::CellIterator(Cell begin, Cell end, Cell state)
+: state{ state } , begin{ begin }, end{ end } {}
+
+CellIterator &CellIterator::operator++() {
+	++(this->state.x);
+	if (this->state.x == this->end.x) {
+		this->state.x = this->begin.x;
+		this->state.y = SDL_min(this->state.y + 1, this->end.y);
+	}
+	return *this;
+}
+
+CellIterator &CellIterator::operator--() {
+	--(this->state.x);
+	if (this->state.x == this->begin.x) {
+		this->state.x = this->end.x - 1;
+		this->state.y = SDL_max(this->state.y - 1, this->begin.y);
+	}
+	return *this;
+}
+
+bool CellIterator::operator==(CellIterator const &src) const {
+	return src.begin == this->begin && src.end == this->end && (src.state == this->state || src.at_end() == this->at_end());
+}
+
+bool CellIterator::operator!=(CellIterator const &src) const {
+	return src.begin != this->begin || src.end != this->end || (src.state != this->state && src.at_end() != this->at_end());
+}
+
+Cell const &CellIterator::operator*() const {
+	return state;
+}
+
+bool CellIterator::at_end() const {
+	return this->state.y == this->end.y;
+}
+
+static std::vector<Cell> NeighborSet(Cell cell) {
+	std::vector<Cell> out{};
+	for (Cell const &c : CellRange{ { cell.x - 1, cell.y - 1 }, { cell.x + 2, cell.y + 2 } }) {
+		if (likely(c != cell)) {
+			out.push_back(c);
+		}
+	}
+	return out;
+}
+
+static size_t CountNeighbors(Cell const &cell) {
+	size_t count{ 0 };
+	for (Cell const &c : CellRange{ {cell.x - 1, cell.y - 1}, { cell.x + 2, cell.y + 2} }) {
+		if (c != cell && living.contains(c)) {
+			++count;
+		}
+	}
+	return count;
+}
+
+static void PopulateChanges() {
+	overpopulated.clear();
+	underpopulated.clear();
+	born.clear();
+	// TODO: consider multithreading, this is highly parallelisable
+	std::ranges::copy_if(living, std::back_inserter(overpopulated),
+	[&](Cell const &c) -> bool {
+		size_t const neighbors{ CountNeighbors(c) };
+		return neighbors > 3;
+	});
+	std::ranges::copy_if(living, std::back_inserter(underpopulated),
+	[&](Cell const &c) -> bool {
+		size_t const neighbors{ CountNeighbors(c) };
+		return neighbors < 2;
+	});
+	for (Cell const &cell : living) {
+		std::vector<Cell> neighbors{ NeighborSet(cell) };
+		std::ranges::copy_if(neighbors, std::back_inserter(born),
+		[&](Cell const &c) -> bool {
+			size_t const neighbors{ CountNeighbors(c) };
+			return !living.contains(c) && neighbors == 3;
+		});
+	}
+}
+
+void InitializeRandom(size_t livingChance, int64_t fillArea) {
+	living.clear();
+	Cell itr{ 0, 0 };
+	while (itr.y < fillArea) {
+		if (std::rand() % livingChance == 0	) {
+			living.insert(itr);
+		}
+		++itr.x;
+		if (itr.x == fillArea) {
+			itr.x = 0;
+			++itr.y;
+		}
+	}
+	PopulateChanges();
+}
+
+void Step() {
+	for (Cell const &cell : underpopulated) {
+		living.erase(cell);
+	}
+	for (Cell const &cell : overpopulated) {
+		living.erase(cell);
+	}
+	for (Cell const &cell : born) {
+		living.insert(cell);
+	}
+	PopulateChanges();
+}
+
+static bool simulationHovered{ false };
+static SDL_FPoint viewOffset{ 0, 0 };
+
+void Draw(SDL_Renderer *renderer, double cellSizePercent) {
+	if (simulationHovered) {
+		viewOffset.x += input::scrollMotion.x;
+		viewOffset.y += input::scrollMotion.y;
+	}
+	int w;
+	SDL_GetCurrentRenderOutputSize(renderer, &w, nullptr);
+	float const cellWidth = static_cast<float>(w) * cellSizePercent;
+	SDL_FRect cellRect{
+		0, 0, cellWidth, cellWidth
+	};
+	SDL_SetRenderDrawColor(renderer, 255, 255, 255, 255);
+	for (Cell const &cell : living) {
+		cellRect.x = (viewOffset.x + cell.x) * cellRect.w;
+		cellRect.y = (viewOffset.y + cell.y) * cellRect.h;
+		SDL_RenderFillRect(renderer, &cellRect);
+	}
+	SDL_SetRenderDrawColor(renderer, 255, 0, 0, 255);
+	for (Cell const &cell : overpopulated) {
+		cellRect.x = (viewOffset.x + cell.x) * cellRect.w;
+		cellRect.y = (viewOffset.y + cell.y) * cellRect.h;
+		SDL_RenderRect(renderer, &cellRect);
+	}
+	SDL_SetRenderDrawColor(renderer, 255, 0, 255, 255);
+	for (Cell const &cell : underpopulated) {
+		cellRect.x = (viewOffset.x + cell.x) * cellRect.w;
+		cellRect.y = (viewOffset.y + cell.y) * cellRect.h;
+		SDL_RenderRect(renderer, &cellRect);
+	}
+	SDL_SetRenderDrawColor(renderer, 0, 255, 0, 255);
+	for (Cell const &cell : born) {
+		cellRect.x = (viewOffset.x + cell.x) * cellRect.w;
+		cellRect.y = (viewOffset.y + cell.y) * cellRect.h;
+		SDL_RenderRect(renderer, &cellRect);
+	}
+}
+
+void SetSimulationHovered(bool value) {
+	simulationHovered = value;
+}
+bool operator==(Cell const &lhs, Cell const &rhs) {
+	return lhs.x == rhs.x && lhs.y == rhs.y;
+}
+bool operator!=(Cell const &lhs, Cell const &rhs) {
+	return lhs.x != rhs.x || lhs.y != rhs.y;
+}
+
+bool operator<(Cell const &lhs, Cell const &rhs) {
+	uintptr_t hashl{ uintptr_t(lhs.x * 73856093) ^ uintptr_t(lhs.y * 19349663) };
+	uintptr_t hashr{ uintptr_t(rhs.x * 73856093) ^ uintptr_t(rhs.y * 19349663) };
+	return hashl < hashr;
+}
+}
diff --git a/src/simulation.h b/src/simulation.h
new file mode 100644
index 0000000..b0699ba
--- /dev/null
+++ b/src/simulation.h
@@ -0,0 +1,48 @@
+#ifndef SIMULATION_H
+#define SIMULATION_H
+
+#include <SDL3/SDL_rect.h>
+#include <SDL3/SDL_render.h>
+#include <clay/clay.h>
+#include <set>
+
+namespace simulation {
+struct Cell {
+	int64_t x{ 0 }, y{ 0 };
+
+};
+
+class CellIterator {
+friend class CellRange;
+public: CellIterator(Cell begin, Cell end);
+	CellIterator &operator++();
+	CellIterator &operator--();
+	CellIterator &operator=(CellIterator const &src);
+	bool operator==(CellIterator const &src) const;
+	bool operator!=(CellIterator const &src) const;
+	Cell const &operator*() const;
+	bool at_end() const;
+private: CellIterator(Cell begin, Cell end, Cell state);
+	Cell state{ 0, 0 };
+	Cell begin{ 0, 0 }, end{ 0, 0 };
+};
+
+class CellRange {
+private:
+	Cell beginCell{ 0, 0 }, endCell{ 0, 0 };
+public: CellRange(Cell begin, Cell end) : beginCell{ begin }, endCell{ end } {}
+	CellIterator begin() { return CellIterator{ beginCell, endCell }; }
+	CellIterator end() { return CellIterator{ beginCell, endCell, endCell }; }
+};
+
+void InitializeRandom(size_t livingChance, int64_t fillArea);
+void Step();
+void Draw(SDL_Renderer *renderer, double cellSizePercent);
+void SetSimulationHovered(bool value);
+
+bool operator==(Cell const &lhs, Cell const &rhs);
+bool operator!=(Cell const &lhs, Cell const &rhs);
+bool operator<(Cell const &lhs, Cell const &rhs);
+}
+
+#endif // !SIMULATION_H
diff --git a/src/style.cpp b/src/style.cpp
new file mode 100644
index 0000000..6816639
--- /dev/null
+++ b/src/style.cpp
@@ -0,0 +1,87 @@
+#include "style.h"
+#include "resources.h"
+#include <clay/clay.h>
+
+namespace style {
+Clay_ElementDeclaration ListContainer(size_t depth, Clay_ElementDeclaration baseCfg) {
+	baseCfg.border = {
+		PanelBorder(depth),
+		CLAY_BORDER_ALL(2)
+	};
+	baseCfg.cornerRadius = defaultRadiusAll;
+	return baseCfg;
+}
+
+Clay_ElementDeclaration PanelContainer(size_t depth, Clay_ElementDeclaration baseCfg) {
+	baseCfg.backgroundColor = PanelBackground(depth);
+	baseCfg.border = {
+		PanelBorder(depth),
+		CLAY_BORDER_OUTSIDE(2)
+	};
+	baseCfg.cornerRadius = defaultRadiusAll;
+	baseCfg.layout.padding = CLAY_PADDING_ALL(16);
+	return baseCfg;
+}
+
+Clay_ElementDeclaration LeftPanelContainer(size_t depth, Clay_ElementDeclaration baseCfg) {
+	baseCfg = PanelContainer(depth, baseCfg);
+	baseCfg.border.width = { 0, 2, 2, 2, 0 };
+	baseCfg.cornerRadius = { 0, defaultRadius, 0, defaultRadius };
+	baseCfg.layout.sizing.height = CLAY_SIZING_GROW();
+	return baseCfg;
+}
+
+Clay_ElementDeclaration RightPanelContainer(size_t depth, Clay_ElementDeclaration baseCfg) {
+	baseCfg = PanelContainer(depth, baseCfg);
+	baseCfg.border.width = { 2, 0, 2, 2, 0 };
+	baseCfg.cornerRadius = { defaultRadius, 0, defaultRadius, 0 };
+	baseCfg.layout.sizing.height = CLAY_SIZING_GROW();
+	return baseCfg;
+}
+
+Clay_Color PanelBackground(size_t idx) {
+	return {
+		255*panelBackground[idx],
+		255*panelBackground[idx],
+		255*panelBackground[idx],
+		255
+	};
+}
+
+Clay_Color PanelBorder(size_t idx) {
+	return {
+		255*panelBorder[idx],
+		255*panelBorder[idx],
+		255*panelBorder[idx],
+		255
+	};
+}
+
+Clay_Color TextColors(size_t idx) {
+	return {
+		255*textColorsP[idx],
+		255*textColorsP[idx],
+		255*textColorsP[idx],
+		255
+	};
+}
+
+Clay_ElementDeclaration Window() {
+	return {
+		.layout = {
+			.sizing = { CLAY_SIZING_GROW(), CLAY_SIZING_GROW() },
+			.padding = CLAY_PADDING_ALL(0),
+			.childGap = 0,
+			.layoutDirection = CLAY_LEFT_TO_RIGHT,
+		},
+	};
+}
+
+Clay_Color ToHoveredColor(Clay_Color color) {
+	float avg = (color.r + color.g + color.b) / 3.f;
+	color.r = (color.r - avg) * 0.8f + avg - 30;
+	color.g = (color.g - avg) * 0.8f + avg - 30;
+	color.b = (color.b - avg) * 0.8f + avg - 30;
+	return color;
+}
+}
diff --git a/src/style.h b/src/style.h
new file mode 100644
index 0000000..b395821
--- /dev/null
+++ b/src/style.h
@@ -0,0 +1,109 @@
+#ifndef STYLE_H
+#define STYLE_H
+
+#include <clay/clay.h>
+#include <stdint.h>
+
+namespace style {
+////////////////////////////////////
+// WINDOW STYLE
+////////////////////////////////////
+
+constexpr uint16_t windowPadding{ 10 };
+
+////////////////////////////////////
+// CONTAINER STYLE
+////////////////////////////////////
+
+constexpr uint16_t containerGap{ 10 };
+constexpr double defaultRadius{ 5.0 };
+
+constexpr float panelBackground[] = {
+	.2f, .3f, .4f
+};
+constexpr float panelBorder[] = {
+	.3f, .4f, .5f
+};
+
+constexpr Clay_Padding panelPadding = {
+	24, 24,
+	24, 24,
+};
+
+Clay_ElementDeclaration ListContainer(size_t depth, Clay_ElementDeclaration baseCfg);
+Clay_ElementDeclaration PanelContainer(size_t depth, Clay_ElementDeclaration baseCfg);
+Clay_ElementDeclaration LeftPanelContainer(size_t depth, Clay_ElementDeclaration baseCfg);
+
+////////////////////////////////////
+// TEXT STYLE
+////////////////////////////////////
+
+constexpr float paragraphGap = 10;
+constexpr uint16_t baseFontSize = 16;
+constexpr float textColorsP[] = {
+	0.9f, 0.9f, 0.9f
+};
+
+constexpr uint16_t headerSizes[] = {
+	64, 32,
+	28, 16
+};
+
+////////////////////////////////////
+// BUTTONS
+////////////////////////////////////
+
+constexpr Clay_Color warningButton = {
+	177, 56, 52, 255
+};
+constexpr Clay_Color proceedButton = {
+	49, 181, 99, 255
+};
+constexpr Clay_Color actionButton = {
+	49, 142, 181, 255
+};
+
+constexpr Clay_Padding buttonPadding = {
+	24, 24,
+	4, 4,
+};
+constexpr Clay_CornerRadius buttonRadii = {
+	3, 3, 3, 3
+};
+
+constexpr Clay_Color dieColors[] = {
+	{ 230, 184, 48, 255 },
+	{ 177, 56, 52, 255 },
+	{ 115, 177, 52, 255 },
+	{ 52, 177, 125, 255 },
+	{ 52, 177, 176, 255 },
+	{ 52, 93, 177, 255 },
+	{ 177, 52, 140, 255 },
+	{ 95, 52, 177, 255 },
+};
+
+////////////////////////////////////
+// COMPILATIONS
+// | Functions and expressions that combine styling data from the settings above.
+////////////////////////////////////
+
+constexpr Clay_Sizing layoutExpand = {
+	.width = CLAY_SIZING_GROW(0),
+	.height = CLAY_SIZING_GROW(0)
+};
+
+constexpr Clay_CornerRadius defaultRadiusAll = {
+	defaultRadius, defaultRadius,
+	defaultRadius, defaultRadius
+};
+
+Clay_Color PanelBackground(size_t idx);
+Clay_Color PanelBorder(size_t idx);
+Clay_Color TextColors(size_t idx);
+Clay_Color WindowBackground();
+Clay_ElementDeclaration Window();
+Clay_Color ToHoveredColor(Clay_Color color);
+
+}
+
+#endif // !STYLE_H