/* body selector here */

body {
  background-image: url('https://images.unsplash.com/photo-1601370690183-1c7796ecec61?fm=jpg&q=60&w=3000&ixlib=rb-4.1.0&ixid=M3wxMjA3fDB8MHxzZWFyY2h8Mnx8Z3JlZW4lMjBiYWNrZ3JvdW5kfGVufDB8fDB8fHww');
  background-size: cover;
}

/* main */

.main {
  text-align: center;
  color: aliceblue;
  margin-top: 150px;
  font-size: xx-large;
  font-family:'Trebuchet MS', 'Lucida Sans Unicode', 'Lucida Grande', 'Lucida Sans', Arial, sans-serif;
}

/* header */

.header {
  color: rgb(255, 208, 0);
}

/* buttons */

button {
  background-color: yellow;
  color: darkgreen;
  border: 0px;
  border-radius: 4px;
  padding: 10px 30px;
  font-size: x-large;
  font-weight: bold;
  display: block;        /* takes full width line */
  margin: 10px auto; 
}