header {
  height: 100px;
  width: 100%;
  /* Sets border to bottom only */
  border-bottom: 10px solid darkblue;
  background-color: #999900;
}

section {
  width: 70%;
  /* Sets top and bottom margin to 20px. Auto will center element */
  margin: 20px auto;
  border-bottom: 5px solid darkblue;
  background-color: #ffffd4;
}

h1 {
  text-align: center;
  line-height: 100px;
}

h2 {
  /* Sets bottom margin to 0 */
  margin-bottom: 10px;
}

h3 {
  /* Sets top margin to 0 */
  margin-top: 10px;
}

.example-box {
  /* Shortcut method sets top and bottom padding to 20px and left and right to 40px */
  padding: 20px 40px;
}

.image-padding {
  /* Sets padding on all sides to 20px */
  padding: 40px;
  background-color: #999900;
}

.image-border {
  /* Sets border on all sides */
  border: 20px solid darkblue;
}

.image-margin {
  /* Sets all sides to 20px */
  margin: 20px;
}