text: /**
   * request the score board from the server
   */
  function showScoreboard()
  {
      let scoreboard = document.getElementById("score_entries");
      if(scoreboard.style.display == "table")
      {
          scoreboard.style.display = "none";
      }
      else
      {
          scoreboard.style.display = "table";
      }
  }
  
  /**
   * sends a score to the server
   * 
   * @param {string} name user name 
   * @param {number} score score
   */
  function sendScore(name, score)
  {
      let xhttp = new XMLHttpRequest();
      xhttp.open("POST","./php/Scores.php");
      xhttp.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
      xhttp.send(`name=${name}&score=${score}`);
  }
  
  // separate html from js
  window.addEventListener("load",() => document.getElementById("show_scoreboard").addEventListener("click", showScoreboard));