*,
*::before,
*::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  width: 100dvw;
  height: 100dvh;
  overflow-x: hidden;
}

main {
  width: 100%;
  max-width: 720px;
  margin: 0 auto;
  position: relative;
}

img {
  display: block;
  width: 100%;
}

img#footer {
  position: sticky;
  bottom: 0;
  left: 0;
}