body {
  font-family: Arial, sans-serif;
  margin: 0;
  padding: 0;
}
header,
main {
  padding: 10px 20px 0 20px;
  max-width: 800px;
  margin: 0 auto;
  /* background-color: #f4f4f4; */
}
.banner-img {
  max-width: 100%;
}