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Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

HTML

            
              <div class="container">
	<div class="score">		
		score: <span class="score_val">0</span>
	</div>
	<div class="canvas-wrapper">
		<canvas width="400" height="400"></canvas>
	</div>
	<div class="controls">
		<button class="btn-start">Start</button>
		<button class="btn-pause">Pause</button>
		<div class="range range-difficulty">
			<label for="difficulty">Speed</label>
			<div class="range_inputWrapper">
				<span class="range_inputSlider"></span>
				<div class="range_inputValue"></div>
				<input type="range" name="difficulty"
				   value="8" min="1" max="10" step="1" >
			</div>
		</div>
		
		<div class="range range-columns">
			<label for="columns">Cells</label>
			<div class="range_inputWrapper">
				<span class="range_inputSlider"></span>
				<div class="range_inputValue"></div>
				<input type="range" name="columns"
			     	value="20" min="10" max="100" step="10">
			</div>
		</div>
	</div>
</div>
            
          
!

CSS

            
              * {
	box-sizing: border-box;
}

html, body {
	width: 100%;
	height: 100%;
	margin: 0;
	background: darken(#00796B, 5%);	
	font-family: 'Varela Round';
}

body {
	display: flex;
	justify-content: center;
	align-items: center;
}

.container {
	width: 90%;
	max-width: 400px;
	border: 5px solid #FFA000;
	border-radius: 3px;
	box-shadow:  10px 10px 50px 15px rgba(black, 0.3);
	background-color: #455A64;
	position: relative;
}

.canvas-wrapper {
	width: 100%;
	height: 0;
	padding-bottom: 100%;
	position: relative;
}

canvas {
	position: absolute;
	top: 0;
	left: 0;
	right: 0;
	bottom: 0;
	height: 100%;
	width: 100%;
	background-color: #37474F;
}

.controls {
	width: 100%;
	padding-top: 20px;
	padding-bottom: 0;
	display: flex;
	justify-content: space-between;
	flex-wrap: wrap;
}

button[class^="btn"] {
	background-color: #FFA000;
	padding: 5px 20px;
	text-transform: uppercase;
	font-family: 'Varela Round';
	font-size: 14px;
	color: white;
	font-weight: bold;
	border: none;
	border-radius: 3px;
	letter-spacing: 0.3em;
	height: 30px;
	line-height: 30px;
	padding: 0 10px;
	box-shadow: 0 0 10px 5px rgba(black, 0.2);
	outline: none;
	cursor: pointer;
	transition: box-shadow 0.3s, background 0.3s;
	text-align: center;
	
	margin: 0 20px 0;
	margin-bottom: 20px;
	&:hover {
		background: lighten(#FFA000, 10%);
		box-shadow: 0 0 20px 5px rgba(black, 0.3);
	}
	
	@media(min-width: 450px) {
		& {
			width: 150px;
		}
	}
}

button[disabled] {
	background: darken(#FFA000, 10%);
}

.range {
	width: 100%;
	margin-bottom: 20px;
	margin: 0 20px 20px;
	
	display: flex;
	align-items: center;
	
	label {
		color: white;
		text-transform: uppercase;
		margin-right: 20px;
		width: 30%;
	}
	
	&_inputWrapper {
		width: 100%;
		position: relative;
		height: 20px;
		background-color: #fff;		
		box-shadow: 0 0 10px 5px rgba(black, 0.2);
	}
	
	&_inputValue {
		position: absolute;
		left: 0;
		top: 0;
		height: 100%;
		color: white;
		font-size: 14px;
		height: 100%;
		padding-left: 3px;
		line-height: 20px;
	}
	
	&_inputSlider {
		transform-origin: left top;
		position: absolute;
		top: 0;
		left: 0;
		background: #FFA000;
		display: inline-block;
		width: 100%;
		height: 100%;
		transform: scaleX(0);
		transition: transform 0.2s ease-out;
	}
	
	input {	
		position: absolute;
		left: 0;
		top: 0;
		height: 100%;
		width: 100%;
		margin: 0;
		opacity: 0;
		cursor: ew-resize;
		z-index: 1
	}
}

.score {
	position: absolute;
	top: 10px;
	left: 0;
	z-index: 1;
	width: 100%;
	text-align: center;
	font-weight: bold;
	font-size: 30px;
	opacity: 0.3;
	text-transform: uppercase;
	color: white;
}

.dpad {
	width: 100px;
	margin: 0 auto;
	margin-bottom: 20px;
	display: none;
}

button[class^="control"] {
	background: #FFA000;
	border: none;
	border-radius: 3px;
	
	
}

.control-up {
	display: block;
}
.control-down svg {
	transform: rotate(180deg)
}
.control-left svg {
	transform: rotate(90deg)
}
.control-right svg {
	transform: rotate(-90deg)
}
            
          
!

JS

            
              let cellsNo = 20
let cellSize = 400 / cellsNo
let difficulty = 1

let score = 0

const canvas = document.querySelector('canvas')
const ctx = canvas.getContext('2d')

const btnStart = document.querySelector('.btn-start')
const btnPause = document.querySelector('.btn-pause')
const scoreVal = document.querySelector('.score_val')


let direction
const DIR = {
	LEFT: 37,
	UP: 38,
	RIGHT: 39,
	DOWN: 40
}

// ctx.strokeStyle = '#616161'
ctx.strokeStyle = '#27373F'
ctx.fillStyle = '#fff'

let snake = []
let food = null
let paused = false
let needsGrowth = false

let lastUpdate, lastFood, tick
let state
let flash = false
let lastKeyPressed

function update() {
	tick = Date.now()
	
	
	if (hasCollisions()) {
		flash = true
		return
	}
	
	if (tick - lastUpdate > 500 / difficulty) {
		if (lastKeyPressed && lastKeyPressed !== direction) {
			setDirection(lastKeyPressed)
		}
		
		moveSnake()
		lastUpdate = tick
	}
	
	if (tick - lastFood > foodTreshold()) {
		putFood()
	}
	
	if (headMeetsFood()) {
		needsGrowth = true
		food = null
		putFood()
		setScore(score + difficulty)
	}
}

function foodTreshold() {
	return (5000 / difficulty) * cellsNo
}

function hasCollisions() {
	const head = snake[0]
	const check = snake.concat([])
	check.shift()
	return check.find(
		c => c.x === head.x && c.y === head.y
	)
}

function snakeContains(cell) {
	return snake.find(c => c.x === cell.x && c.y === cell.y)
}

function headMeetsFood() {
	const head = snake[0]
	return food && (head.x == food.x && head.y === food.y)
}

function moveSnake() {
	const head = snake[0]
	const next = Object.assign({}, head)
	
	switch(direction) {
		case DIR.LEFT:
			--next.x;
			break;
		case DIR.UP:
			--next.y;
			break;
		case DIR.RIGHT:
			++next.x;
			break;
		case DIR.DOWN:
			++next.y;
			break;
	}
	
	if (next.x >= cellsNo) next.x = 0
	if (next.y >= cellsNo) next.y = 0
	if (next.x < 0) next.x = cellsNo -1
	if (next.y < 0) next.y = cellsNo -1

	if (!needsGrowth) {
		snake.pop()
	}
	
	needsGrowth = false
	snake.unshift(next);
}

function putFood() {
	do {
		food = {
			x: ~~(Math.random() * (cellsNo - 1)),
			y: ~~(Math.random() * (cellsNo - 1))
		}
	} while (snakeContains(food))
	
	lastFood = tick
}

function draw() {
	ctx.clearRect(0, 0, 400, 400)
	drawCells()
	drawFood()
	if (flash && ~~(Date.now() / 100) % 2 === 0) {
		return
	}
	drawSnake()
}

function drawCells() {
	for (var i = 0; i < cellsNo; ++i)
		for (var j = 0; j < cellsNo; ++j) 
			drawCell(i, j)
}

function drawFood() {
	if (food) {	
		ctx.fillStyle = '#4FC3F7'
		fillCell(food.x, food.y)
		ctx.fillStyle = '#fff'
	}
}

function drawCell(i, j) {
	ctx.strokeRect(
		i * cellSize, 
		j * cellSize, 
		cellSize, cellSize
	)
}

function drawSnake() {
	snake.forEach(
	 ({x, y}) => fillCell(x, y)
	)
}

function fillCell(x, y) {
	ctx.beginPath()
	ctx.rect(
		x * cellSize, 
		y * cellSize, 
		cellSize, cellSize
	)
	
	ctx.closePath()
	ctx.fill()
	ctx.stroke()
} 

function setScore(next) {
	score = next
	scoreVal.textContent = score
}

function startGame() {
	btnStart.textContent = 'restart'
	flash = false
	lastKeyPressed = null
	food = null
	setScore(0)
	direction = DIR.LEFT
	lastFood = lastUpdate = Date.now()
	paused = false
	setTimeout(putFood, 1000)
	const startX = cellsNo/2
	snake = [startX, startX+1, startX+2, startX+3].map(
		x => ({x, y: 15})
	)
}

function loop() {
	requestAnimationFrame(loop)
	draw()
	
	if (paused) return
	update()
}

requestAnimationFrame(loop)

btnStart.addEventListener('click', startGame)
btnPause.addEventListener('click', pause)

function pause() {
	paused = !paused
	btnPause.textContent = paused ? 'resume' : 'pause'
}

window.addEventListener('keydown', onKeyDown)
function onKeyDown({keyCode}) {
	switch (true) {
		case (keyCode === DIR.DOWN && direction === DIR.UP):
		case (keyCode === DIR.UP && direction === DIR.DOWN):	
		case (keyCode === DIR.LEFT && direction === DIR.RIGHT):
		case (keyCode === DIR.RIGHT && direction === DIR.LEFT):
			return 
	}
	
	lastKeyPressed = keyCode
}

function setDirection(keyCode) {
	direction = keyCode
}

function checkFood() {
	if (!food) return
	
	if (food.x >= cellsNo) {
		food.x = cellsNo -1
	}
	
	if (food.y >= cellsNo) {
		food.y = cellsNo -1
	}
}

class RangeSlider {
	constructor(el, cb) {
		this.input = el.querySelector('input')
		this.slider = el.querySelector('.range_inputSlider')
		this.value = el.querySelector('.range_inputValue')
		
		this.input.addEventListener('input', _ => this.onChange())
		this.input.addEventListener('keydown', e => {
			e.preventDefault()	
		})
		
		this.onChangeCallback = cb
		this.onChange()
	}
	
	onChange() {
		this.value.textContent = this.input.value
		this.slider.style.transform = `scaleX(${(this.input.value / this.input.step) / 10})`
		this.onChangeCallback(this.input.value)
	}
}


new RangeSlider(
	document.querySelector('.range-difficulty'), 
	value => difficulty = Number(value)
)
	
new RangeSlider(
	document.querySelector('.range-columns'),
	value => {
		cellsNo = Number(value)
		cellSize = 400 / cellsNo
		checkFood()
	}
)


// --- TOUCH CONTROLS
var isPointerDown, pointerStart, pointerPos

function onTouchStart(e) {
	const {clientX, clientY} = e.touches[0]
    isPointerDown = true
	pointerStart = {x: clientX, y: clientY}
	pointerPos = Object.assign({}, pointerStart)
}

function onTouchMove(e) {
	const {clientX, clientY} = e.touches[0]
    pointerPos = {x: clientX, y: clientY}
}

function onTouchEnd() {
	if (!isPointerDown) return
	isPointerDown = false
	
	const deltaX = pointerStart.x - pointerPos.x
	const deltaY = pointerStart.y - pointerPos.y
	const keyCode = touchToKeyCode(deltaX, deltaY)
	
	if (keyCode) onKeyDown({keyCode})
}
 
function touchToKeyCode(x, y) {
	if (Math.abs(x) > Math.abs(y)) {
		if (x < -1) {
			keyCode = DIR.RIGHT
		} else if (x > 1) {
			keyCode = DIR.LEFT
		} 
	} else {
		if (y < -1) {
			keyCode = DIR.DOWN
		} else if (y > 1) {
			keyCode = DIR.UP
		}
	}
	
	return keyCode
}


canvas.addEventListener('touchstart', onTouchStart)
window.addEventListener('touchmove', onTouchMove)
window.addEventListener('touchend', onTouchEnd)
            
          
!
999px

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