* {
  box-sizing: border-box;
}

body {
  font-family: Arial, Helvetica, sans-serif;
}

/* Style the header */
header {
  background-color: firebrick;
  padding: 50px;
  text-align: Left;
  font-size: 30px;
  color: Black;
  Border-style: Solid;
  Border-width: 1.5px;
  Font-family: Copperplate;
  background-image: Url(https://www.betsson.com/wp-content/uploads/2017/05/4_3_Card_Poker_Header_1140x400.jpg.optimal.jpg)
}

/* styles for desktop devices */
@media only screen and (min-width: 992px) {
  body {
    font-size: 16px;
    width: 80%;
    margin: auto;
  }
}

/* styles for tablet devices */
@media only screen and (min-width: 768px) and (max-width: 991px) {
  body {
    font-size: 14px;
    width: 90%;
    margin: auto;
  }
}

/* styles for mobile devices */
@media only screen and (max-width: 767px) {
  body {
    font-size: 12px;
    width: 100%;
    margin: 0;
  }
}

/* Style the top navigation bar */
.topnav {
  overflow: hidden;
  background-color: olivedrab;
}

/* Style the topnav links */
.topnav a {
  float: left;
  display: block;
  color: black;
  text-align: right;
  padding: 10px 16px;
  text-decoration: underline;
}

article {
  float: left;
  padding: 10px;
  width: 100%;
  background-color: #b24040;
  height: 300px; 
  Border-style: Solid;
  Border-width: 1.5px;
  Font-family: Copperplate;
}

/* Clear floats after the columns */
section::after {
  content: "";
  display: table;
  clear: both;
}

/* Style the footer */
footer {
  background-color: Dimgrey;
  padding: 10px;
  text-align: center;
  color: white;
  Font-family: Copperplate;
}

/* Responsive layout - makes the two columns/boxes stack on top of each other instead of next to each other, on small screens */
@media (max-width: 600px) {
  nav, article {
    width: 100%;
    height: auto;
  }
}