script.js

let display=document.getElementById('display');


let buttons=Array.from(document.getElementsByClassName('button'));

buttons.map(button=>{
    button.addEventListener('click',(e)=>{
       switch(e.target.innerText){
           case 'C':display.innerText='';
           break;
           case'←':
             if(display.innerText){
                display.innerText=display.innerText.slice(0,-1);
             }
           break;
           case '=':
               try{display.innerText=eval(display.innerText);}
               catch{
                   display.innerText='Error!'
               }
           break;
           default: display.innerText+=e.target.innerText;
              
       };
    });
});