html {
  height: 100%; 
}

body {
  min-height: 100vh;
  display: flex;
  flex-direction: column; 
  margin: 0; 
}

main {
  flex-grow: 1; 
}

article{
  max-width: 1280px;
  margin-left: auto;
  margin-right: auto;
  padding-left: 20px;
  padding-right: 20px;
  box-sizing: border-box; 
}

article img{
  width: 100%; 
  height: auto;
}

article h3{
  font-weight: 300;
}

article strong{
  font-weight: 600;
}