Memory with Litecanvas

code.js

litecanvas({})

let cards = [], sprites, opens = [], timer = 0, score = 0

const 
  SIZE = 64,
  OFFSET = SIZE/1.5,
  CLOSED_CARD = paint(SIZE, SIZE, () => {
    cls(2)
  })
  

function init() {
  textfont(PIXEL_FONT_MONOGRAM)
  textsize(3)
  
  for (let i = 0; i < 16; i++) {
    const sprite = paint(SIZE, SIZE, () => {
      cls(1)
      text(SIZE/4,SIZE/3, lpad(i,2,'0'))
    })
    
    cards.push(
      card(sprite),
      card(sprite)
    )
  }

  cards = shuffle(cards)

  for (let i = 0; i < cards.length; i++) {
    cards[i].sprite1.x = cards[i].sprite2.x = OFFSET/2 + (i % 8) * (SIZE + SIZE/4)
    cards[i].sprite1.y = cards[i].sprite2.y = OFFSET + floor(i/8) * (SIZE + SIZE/4)
  }
}

function update(dt) {
  timer -= dt
  if (timer <= 0 && opens.length === 2) {
    opens[0].open = opens[1].open = false
    opens.length = 0
  }
}

function tapped(x, y) {
  if (opens.length === 2) return
  if (timer > 0) return
  
  for (let i = 0; i < cards.length; i++) {
    if (cards[i].sprite1.in(x, y)) {
      if (!cards[i].open) {
        cards[i].open = true
        opens.push(cards[i])
      }
      if (opens.length > 1) {
        if (opens[0].img === opens[1].img) {
          timer = 0.25
          opens.length = 0
          score++
          sfx()
        } else {
          timer = 1
        }
      }
      break;
    }
  }
}

function draw() {
  cls(0)

  for (let i = 0; i < cards.length; i++) {
    if (cards[i].open) {
      cards[i].sprite1.draw()
    } else {
      cards[i].sprite2.draw()
    }
  }

  text(OFFSET/2, 2, 'score: ' + score)
}

function card(img) {
  const obj = {
    img,
    sprite1: new Actor(img),
    sprite2: new Actor(CLOSED_CARD),
    open: false
  }
  return obj
}

Live Demo