lab 4.3

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <title>zadaca3</title>
  <style>
    #gore {
      margin-left: 80px;
      padding-bottom: 10px;
    }

    button {
      margin-top: 10px;
      margin-left: 133px;
    }
    #containter{
      display: inline-block;
      margin-left: 35%;
      margin-top: 25%;
    }
  </style>

</head>
<body>
<div id="containter">
  <div id="gore">
    <input type="radio" value="color" name="selektor" checked>Color
    <input type="radio" value="image" name="selektor">Image<br>
  </div>
  <div>
    <label>Value: </label><input type="text" id="vid"><br>
    <button onclick="promeni();">Промени</button>
  </div>
</div>
</body>
</html>
  <script>
    function promeni() {
      document.body.style.backgroundImage = "";
      var radios = document.getElementsByName('selektor');
      var input = document.getElementById('vid').value;
      if (radios[0].checked == true) {
        document.body.style.backgroundColor = input;
      }
      else if (radios[1].checked == true) {
        document.body.style.backgroundImage = "url('"+input+"')";
      }
    }
  </script>