style.css

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

a, a:hover {
  color: red;
  text-decoration: none;
}

html, body {
  font-family: Arial, sans-serif;
  line-height: 1.6;
}

h1, h2, h3, h4, h5, h6 {
  text-align: center;
}

img {
  max-width: 100%;
  height: auto;
}

ul {
  list-style: none;
}

ul li:before {
  content: "— ";
}

main, section {
  padding: 10px;
  margin: 0 auto;
  max-width: 768px;
}