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                <section class="canvas">

<section class="toolbox">
  <div class="canvas-tools">

  <div class="painting-tools">
    <h2>Painting tools</h2>

  <div class="styles-tools">

  <div class="background-tools">

<script src=""></script>
<script src="paintbrushes.js"></script>
<script src="app.js"></script>


                @import url('');

body {
	margin: 0;
	overflow: hidden;
	background-color: #ffffff;

	font-family: Nunito, sans-serif;
	font-size: 14px;
	line-height: 1;

section {
	height: 100vh;
	position: fixed;
	top: 0;

section.toolbox {
	right: 0;
	width: 180px;
	overflow-y: scroll;

	background-color: white;
	border-left: 1px solid #545454;

	display: flex;
	flex-direction: column;

section.canvas {
	left: 0;
	width: calc(100vw - 180px);

	display: flex;
	justify-content: center;
	align-items: center;

section.toolbox > div {
	padding: 20px 16px 8px 16px;
	border-bottom: 1px solid #545454;

h2 {
	margin-bottom: 24px;

	font-family: Lexend Deca;
	font-size: 14px;
	text-transform: uppercase;

label {
	display: block;
	margin-bottom: 8px;
	font-size: 14px;

label > * {
	margin-top: 8px;

input, button, select {
	font-size: 14px;
	font-family: Nunito, sans-serif;
	line-height: 1;

	width: 100%;
	height: 32px;
	margin-bottom: 12px;

	border: 1px solid #545454;
	border-radius: 4px;
	background-color: #f0f0f0;

input:hover, button:hover, select:hover {
	background-color: #dfdfdf;

input[type="range"] {
	height: 16px;


                // set up all the global variables
const toolboxWidth = document.querySelector('section.toolbox').offsetWidth
let canvas = null
let bgColor = '#fbf8f3'

let selectedTool = 'pen'
let brushSelector = null

let paintColor = '#000000'
let ifRainbowColor = false
let opacity = 220

function setup() {

  // set up the canvas
  canvas = createCanvas(windowWidth - toolboxWidth, windowHeight)

function setupToolbox() {
  // set up paint style tools in the Styles category
  const paintStyles = select('section.toolbox div.styles-tools')

  // set up canvas tools in the Canvas category
  const canvasTools = select('section.toolbox div.canvas-tools')

  // set up background style tools Background category
  const backgroundStyles = select('section.toolbox div.background-tools')

function setupBrushSelector(parentTag) {
  // create the brush selector as a <select> tag
	brushSelector = createSelect()

  // make a label for the menu
  makeLabel(brushSelector, parentTag, 'Paintbrush style')

  // make an array of all the paintbrush function names
  const brushes = [

  // add in all of the paintbrush function names as menu options
  brushes.forEach(function (brush) {

  // set initial value of the currently selected paintbrush
  selectedTool = brushSelector.value()

  // update the selected paintbrush if the user picks a different menu option
  brushSelector.changed(function () {
    selectedTool = brushSelector.value()

function makeLabel(tag, parentTag, text) {
  const label = createElement('label', text)

function setupButton(text, parentTag, onClick) {
  const button = createButton(text)
  return button

function saveFile() {
  saveCanvas('painting', 'png')

function setupSaveButton(parentTag) {
  setupButton('Save', parentTag, saveFile)

function resetCanvas() {
  // resize canvas to fill the painting area
  resizeCanvas(windowWidth - toolboxWidth, windowHeight)

  // fill canvas with background color

function setupResetButton(parentTag) {
  setupButton('Reset', parentTag, resetCanvas)

function setupColorPicker(initialColor, parentTag, text, onChange) {
  const colorPicker = createColorPicker(initialColor)
  makeLabel(colorPicker, parentTag, text)
  return colorPicker

function setupBgColorPicker(parentTag) {
  const bgColorPicker = setupColorPicker(bgColor, parentTag, 'Background color', function () {
    bgColor = bgColorPicker.color()

function setupPaintColorPicker(parentTag) {
  const paintColorPicker = setupColorPicker(paintColor, parentTag, 'Paint color', function () {
    paintColor = paintColorPicker.color()
    ifRainbowColor = false
  paintColor = paintColorPicker.color()

function setPaintColor() {
  // set color to either rainbow or normal paint color 
	let newColor
  if (ifRainbowColor) {
    const hue = (frameCount * 2) % 360	
    newColor = color(`hsba(${hue}, 100%, 100%, 0.6)`)
  } else {
		newColor = paintColor

  // set the color and opacity of the stroke and fill

function setupRainbowColorButton(parentTag) {
  setupButton('Rainbow color 🌈', parentTag, function () {
    ifRainbowColor = true

// helper function that sets up a slider
function setupSlider(min, max, initialValue, step, text, parentTag, onInput) {
  const slider = createSlider(min, max, initialValue, step)
  makeLabel(slider, parentTag, text)
  return slider

function setupOpacitySlider(parentTag) {
  const opacitySlider = setupSlider(0, 255, opacity, 1, 'Opacity', parentTag, function () {
    opacity = opacitySlider.value()

function draw() {
	// check if mouse button is pressed and mouse is hovering over canvas section
  if (mouseIsPressed && mouseX <= windowWidth - toolboxWidth) {
    // set the paint color

    // draw on the canvas with the selected painting tool function