Shuffle decks in javascript

Shuffle decks in javascript 

<script>

function createCardsforShuffle(){

const suits = ["Spades", "Diamonds", "Club", "Heart"];

const deck = [

  "2",

  "3",

  "4",

  "5",

  "6",

  "7",

  "8",

  "9",

  "10",

  "Jack",

  "Queen",

  "King",

];

let deckvalue = [];

for(var countSuits = 0; countSuits < 4;countSuits++){

// console.log(suits[countSuits]);

for(var countdeck = 0; countdeck < 13;countdeck++){

//console.log(deck[countdeck]);

deckvalue.push(deck[countdeck] + suits[countSuits]);

}

}

return deckvalue;

}

function shuffleCards(decks){

for(var i=0;i<52;i++){

var temp = decks[i];

var randomCards = Math.floor(Math.random() * 52);

decks[i] = decks[randomCards];

decks[randomCards] = temp;

}

}

var testCardsForshuffle = createCardsforShuffle();

shuffleCards(testCardsForshuffle);

console.log(testCardsForshuffle);

</script>