* {
  box-sizing: border-box;
}

body {
  font-family: Arial, sans-serif;
  font-size: 14px;
  line-height: 1.4;
  margin: 0;
}

header {
  padding-left: 20px;
  padding-right: 20px;
  margin-bottom: 20px;
  border-bottom: 4px solid black;
}

h1 {
  font-size: 24px;
}

.wrapper {
  max-width: 1024px; /* Anything within wrapper is restricted to 1024px wide */
  margin: 0 auto; /* Centres content on page */
}

.clearfix:after { /* Solves the zero height container problem when using float. ie stops the footer floating behind body content */
  display: block;
  content: "";
  clear: both;
}

.image {
  color: white;
  width: 200px;
  height: 100px;
  padding: 20px;
}

.image-one {
  background-color: blue;
}

.image-two {
  background-color: red;
}

article {
  padding-left: 20px;
  padding-right: 20px;
  margin-bottom: 20px;
}

.footer {
  background-color: black;
  color: white;
  text-align: right;
  padding: 12px;
}

@media only screen and (min-width: 600px) { /* Responsive breakpoint - targets devices that have a minimum width of 600px and applies these styles */
  body {
    font-size: 16px;
  }

  h1 {
    font-size: 42px;
  }

  .main {
    float: left;
    width: 75%; 
  }

  .sidebar {
    float: ;
    width: 25%;
    border: 2px solid black;
  }

  .image {
    float: left;
    margin-right: 20px;
    margin-bottom: 20px;
  }

  .image-two {
    background-color:purple ;
  }
}