SKI poslednja

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
    <style>
        div{
            border: 1px solid black
        }
        #prav{
            width: 50px;
            height: 150px;
        }
        .krug{
            display: block;
            width: 50px;
            height: 50px;
            border-radius: 50%;

        }
    </style>
</head>
<body>
    <div id="prav">
        <div id="crveni" class="krug"></div>
        <div id="zuti" class="krug"></div>
        <div id="zeleni" class="krug"></div>
    </div>
    <script>
        var t=setInterval(
            var t1=setTimeout(function(){
            document.getElementById("crveni").style.backgroundColor="red"

         ,1000);
    </script>
</body>
</html>


-----------------------------------


<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
</head>
<body>
    <script>
        // var p=document.createElement("p");
        // p.setAttribute("id","p1");
        // document.body.appendChild(p);

        // var t=setInterval(function(){
        //     document.getElementById("p1").innerHTML=new Date();
        // },1000)

        // var t1=setTimeout(function(){
        //     document.getElementById("p1").innerHTML=new Date();
        // },3000)


    </script>
</body>
</html>