#css-page .main-heading {
  color: red;
}

#css-page h1 {
  color: blue;
}

#css-page-1 li[class^="a"] {
  background-color: yellow;
}

#css-page-1 li[class^="a" i] {
  color: red;
}

#css-page-2 .box::after {
  content: " ➥"
}

#css-page-3 .box {
  border: 5px solid rebeccapurple;
  background-color: lightgray;
  padding: 40px;
  margin: 40px;
  width: 300px;
  height: 150px;
  box-sizing: content-box;
}

#css-page-3 .alternate {
  box-sizing: border-box;
}

#css-page-4 .one {
  margin-bottom: 50px;
}

#css-page-4 .two {
  margin-top: 30px;
}

#css-page-5 .links-list a {
  display: inline-block;
  background-color: rgb(179, 57, 81);
  color: #fff;
  text-decoration: none;
  padding: 1em 2em;
}

#css-page-5 .links-list a:hover {
  background-color: rgb(66, 28, 40);
  color: #fff;
}

#css-page-5 ul {
  display: flex;
  list-style: none;
  border: 1px solid black;
}

#css-page-5 li {
  margin: 5px;
}

#css-page-6 header {
  background: purple;
  height: 100px;
}

#css-page-6 h1 {
  text-align: center;
  color: white;
  line-height: 100px;
  margin: 0;
}

#css-page-6 article {
  padding: 10px;
  margin: 10px;
  background: aqua;
  flex: 200px;
}

#css-page-6 section {
  display: flex;
  flex-wrap: wrap;
}

#css-page-7 .container>div {
  border-radius: 5px;
  padding: 10px;
  background-color: rgb(207, 232, 220);
  border: 2px solid rgb(79, 185, 227);
}

#css-page-7 .container {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  grid-gap: 20px;
  grid-auto-rows: minmax(100px, auto);
}

#css-page-7 .first-div{
  grid-column: 1/3;
  grid-row: 1/3;
}

#css-page-8 p {
  width: 400px;
  margin: 0 auto;
}

#css-page-8 p::first-line {
  text-transform: uppercase;
}

#css-page-8 p::first-letter {
  font-size: 3em;
  border: 1px solid black;
  background: red;
  float: left;
  padding: 2px;
  margin-right: 4px;
}

#css-page-9 body,
#css-page-10 body {
  width: 500px;
  margin: 0 auto;
}

#css-page-9 p,
#css-page-10 p {
  background: aqua;
  border: 3px solid blue;
  padding: 10px;
  margin: 10px;
}

#css-page-9 span,
#css-page-10 span {
  background: red;
  border: 1px solid black;
}

#css-page-9 .positioned {
  position: relative;
  background: yellow;
  top: 30px;
  left: 30px;
}

#css-page-10 {
  position: relative;
}

#css-page-10 .positioned {
  position: absolute;
  background: yellow;
  top: 30px;
  left: 30px;
}