script.js

const display = document.querySelector(".display");
const buttons = document.querySelectorAll("button");
const specialChars = ["%", "/", "*", "-", "+", "="];
let output = "";
const calculate = (btnValue) => {
display.focus();
if (btnValue === "=" && output !== "") {
output = eval(output.replace("%", "/100"));
} else if (btnValue === "AC") {
output = "";
} else if (btnValue === "DEL") {
output = output.toString().slice(0, -1);
} else {
if (output === "" && specialChars.includes(btnValue)) return;
output += btnValue;
}
display.value = output;
};
buttons.forEach((button) => {
button.addEventListener("click", (e) => calculate(e.target.dataset.value));
});