p {
  font-size: larger;
  /* So you need to be sure to check spelling because it was spelled as largeerr */
}

h1 {
  font-size: 23xp;
  /* font-size, not fontsize. */
  color: purple;
}

.container {
    /* container NOT contianer */
    color: red;
/* Color NOT colro */
    width: 500px;
    height: 500px;
    background-color: #f0f0f0;
    /* not #f3SupeCoolColor;, it's #f0f0f0*/
}

.output {
  color: #000;
  font-size: 16px;
  font-weight: bold;
  text-align: center;
  margin-top: 20px;
  padding: 10px;
  /*  padding NOT pudding  */
  border: 1px solid #000;
  background-color: #f0f0f0;
}