styles.css

body {
    background-image: url("background-image.jpg");
    background-repeat: no-repeat;
    background-size: cover;
    background-attachment: fixed;
    color: #f5f6f7;
      }

h1, p {
    margin: 1em auto;
    text-align: center;
    font-family:Helvetica;
  }

form {
    width: 60vw;
    max-width: 700px;
    min-width: 300px;
    margin: 0 auto;
    font-family: sans-serif;
    font-size: 18px;
}

fieldset {
    border: none;
    border-radius:15px 15px 0 0;
    background-color: #f5f6f729;
    padding: 50px;
}

#name,#email,#age,#dropdown,#select{
    display: inline-block;
    margin: 10px auto;
    width: 100%;
    height: 30px;
    border-radius: 5px;
    border:hidden;
    
  }

input:placeholder-shown {
    font-size: 0.8em;
  }

hr{
    visibility: hidden;
}

textarea{
    width: 100%;
    margin: 1em auto;
    height: 10em;
    font-size: 0.8em ;
    border-radius: 5px;
    border:hidden
}

input[type="submit"] {
    display: block;
    width: 100%;
    margin: 1em auto;
    border: none;
    height: 3em;
    font-size: 1.1rem;
    background-color: white;
    min-width: 300px;
    border-radius: 5px;
}

input[type=submit]:hover {
  background-color: #f1dcb9;
}