A js calculator

I have been working on a js calc and I need help adding a square root function. Please I need a little help.
This is the html.


<!DOCTYPE html>

<html lang="en">
<head>
    <title>Calculator</title>

    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">

    <link href="https://fonts.googleapis.com/css?family=Roboto:300" rel="stylesheet">
    <link href="Project 1.css" rel="stylesheet">
</head>

<body>
    <header>
        <h1>Calculator</h1>
    </header>

    <main>
        <div id="container">
            <div class="row clearfix">
                <input id="screen" value="0" disabled type="text">
                <button id="clear">AC</button>
            </div>
            <div class="row clearfix">
                <button class="number">1</button>
                <button class="number">2</button>
                <button class="number">3</button>
                <button data-operator="+" class="operator">+</button>
            </div>
            <div class="row clearfix">
                <button class="number">4</button>
                <button class="number">5</button>
                <button class="number">6</button>
                <button data-operator="-" class="operator">-</button>
            </div>
            <div class="row clearfix">
                <button class="number">7</button>
                <button class="number">8</button>
                <button class="number">9</button>
                <button data-operator="*" class="operator">×</button>
            </div>
            <div class="row clearfix">
                <button id="decimal">.</button>
                <button class="number">0</button>
                <button id="equals">=</button>
                <button data-operator="/" class="operator">÷</button>
            </div>
        </div>
    </main>

    <script src="Project 1.js"></script>
</body>
</html>

This is the css

* {
    box-sizing: border-box;
    font-family: 'Roboto', sans-serif;
    font-weight: 300;
    margin: 0;
    padding: 0;
}

body {
    background-color: #222;
    height: 100vh;
}

header {
    background-color: #333;
    padding: 40px 0;
}

header h1 {
    -webkit-background-clip: text;
    background-clip: text;
    background-image: linear-gradient(to right bottom, #fff, #777);
    color: transparent;
    font-size: 40px;
    letter-spacing: 2px;
    text-align: center;
    text-transform: uppercase;
}

main {
    background-color: #222;
    display: flex;
    justify-content: center;
    padding: 60px 0;
}

main #container {
    background-color: #333;
    box-shadow: 0 5px 5px #111;
    padding: 20px;
}

.clearfix:after {
    clear: both;
    content: " ";
    display: block;
    font-size: 0;
    height: 0;
    visibility: hidden;
}

#container .row:not(:last-child) {
    margin-bottom: 9px;
}

#container input,
#container button {
    float: left;
}

#container input:focus,
#container button:focus {
    outline: none;
}

#container input {
    background-color: #222;
    border: 1px solid #999;
    border-right-width: 0;
    color: #999;
    font-size: 22px;
    font-weight: 300;
    height: 80px;
    padding-right: 14px;
    text-align: right;
    width: 261px;
}

#container button {
    background-color: #222;
    border: none;
    box-shadow: 0 3px 0 #111;
    color: #999;
    font-size: 20px;
    height: 80px;
    margin-right: 7px;
    width: 80px;
}

#container button:active {
    box-shadow: 0 2px 0 #111;
    transform: translateY(1px);
}

#container #clear,
#container .operator,
#container #equals {
    color: #111;
}

#container #clear,
#container .operator {
    margin-right: 0;
}

#container #clear {
    background-color: #e95a4b;
    border: 1px solid #999;
    border-left-width: 0;
    box-shadow: none;
    cursor: pointer;
}

#container #clear:active {
    box-shadow: none;
    transform: none;
}

#container .operator {
    background-color: #999;
    box-shadow: 0 3px 0 #555;
}

#container .operator:active {
    box-shadow: 0 2px 0 #555;
}

#container #equals {
    background-color: #2ecc71;
    box-shadow: 0 3px 0 #155d34;
}

#container #equals:active {
    box-shadow: 0 2px 0 #155d34;
}

@media only screen and (max-width: 400px) {
    header {
        padding: 28px 0;
    }

    header h1 {
        font-size: 36px;
    }

    main {
        padding: 40px 0;
    }

    main #container {
        padding: 16px;
    }

    #container .row:not(:last-child) {
        margin-bottom: 7px;
    }

    #container input {
        font-size: 18px;
        height: 60px;
        padding-right: 10px;
        width: 195px;
    }

    #container button {
        font-size: 16px;
        height: 60px;
        margin-right: 5px;
        width: 60px;
    }
}

This is the js

const screen = document.querySelector("#screen");
const clearButton = document.querySelector("#clear");
const equalsButton = document.querySelector("#equals");
const decimalButton = document.querySelector("#decimal");

let isFloat = false;
let signOn = false;
let firstNumber = "";
let operator = "";
let secondNumber = "";
let result = "";

const allClear = () => {
    isFloat = false;
    signOn = false;
    firstNumber = "";
    operator = "";
    secondNumber = "";
    result = "";
    screen.value = "0";
};

const calculate = () => {
    if (operator && result === "" && ![" ", "+", "-", "."].includes(screen.value[screen.value.length - 1])) {
        secondNumber = screen.value.substring(firstNumber.length + 3);

        switch (operator) {
            case "+":
                result = Number((Number(firstNumber) + Number(secondNumber)).toFixed(3));
                break;
            case "-":
                result = Number((Number(firstNumber) - Number(secondNumber)).toFixed(3));
                break;
            case "*":
                result = Number((Number(firstNumber) * Number(secondNumber)).toFixed(3));
                break;
            case "/":
                result = Number((Number(firstNumber) / Number(secondNumber)).toFixed(3));
                break;
            default:
        }
        screen.value = result;
    }
};

clear.addEventListener("click", allClear);

document.querySelectorAll(".number").forEach((numberButton) => {
    numberButton.addEventListener("click", () => {
        if (screen.value === "0") {
            screen.value = numberButton.textContent;
        } else if ([" 0", "+0", "-0"].includes(screen.value.substring(screen.value.length - 2))
                && numberButton.textContent === "0") {
        } else if ([" 0", "+0", "-0"].includes(screen.value.substring(screen.value.length - 2))
                && numberButton.textContent !== "0") {
            screen.value = screen.value.substring(0, screen.value.length - 1) + numberButton.textContent;
        } else if (result || result === 0) {
            allClear();
            screen.value = numberButton.textContent;
        } else {
            screen.value += numberButton.textContent;
        }
    });
});

decimalButton.addEventListener("click", () => {
    if (result || result === 0) {
        allClear();
        isFloat = true;
        screen.value += ".";
    } else if (!isFloat) {
        isFloat = true;
        if ([" ", "+", "-"].includes(screen.value[screen.value.length - 1])) {
            screen.value += "0.";
        } else {
            screen.value += ".";
        }
    }
});

document.querySelectorAll(".operator").forEach((operatorButton) => {
    operatorButton.addEventListener("click", () => {
        if (result || result === 0) {
            isFloat = false;
            signOn = false;
            firstNumber = String(result);
            operator = operatorButton.dataset.operator;
            result = "";
            screen.value = `${firstNumber} ${operatorButton.textContent} `;
        } else if (operator && ![" ", "+", "-", "."].includes(screen.value[screen.value.length - 1])) {
            calculate();
            isFloat = false;
            signOn = false;
            firstNumber = String(result);
            operator = operatorButton.dataset.operator;
            result = "";
            screen.value = `${firstNumber} ${operatorButton.textContent} `;
        } else if (!operator) {
            isFloat = false;
            firstNumber = screen.value;
            operator = operatorButton.dataset.operator;
            screen.value += ` ${operatorButton.textContent} `;
        } else if (!signOn
                && !["*", "/"].includes(operatorButton.dataset.operator)
                && screen.value[screen.value.length - 1] === " ") {
            signOn = true;
            screen.value += operatorButton.textContent;
        }
    });
});

equalsButton.addEventListener("click", calculate);

Please edit it and paste your final result if you can. Or just tell me what you did. Thanks.

You know, I think this would be a great opportunity to make a GitHub repo with the code and let others contribute to it! That way everyone gets access to the final code :smile: and gets you some practice managing pull requests and the other pushing commits!

Thanks for the advice. Please can you give me a link to Github

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Have you ever used GitHub before? If not, I recommend you check these out:

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