demo.css

/*
* Base Template
* Combines HTML5 Boilerplate & Boostrap. Includes some basic templating.
* Authored by Stephen Shaw (shshaw@gmail.com)
*/

/* @group Basics */

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

html,
body {
  margin: 0;
  padding: 0;
  height: 100%;
}

body {
  color: #333333;
  font-weight: 400;
  font-size: 15px;
  font-family: "Helvetica Neue", Helvetica, Arial, sans-serif;
  line-height: 20px;
  margin: 0;
  padding: 4em 0 4em 20%;
}

a {
  color: #da0d25;
  text-decoration: none;
}
a:hover,
a:focus {
  color: #f22840;
  text-decoration: none;
}
p { margin: 0 0 20px; }

h1,
h2,{
  margin: 10px 0;
  font-weight: 500;
  line-height: 40px;
  color: inherit;
  text-align: center;
}
h1 small,
h2 small {
  font-weight: 400;
  line-height: 1;
  color: #8d8d8d;
}
h1 { font-size: 28px; }
h2 { font-size: 22px; }

/* @end */

.main-header {
  position: fixed;
  top: 0;
  bottom: 0;
  left: 0;
  width: 20%;
  background: #eee;
  padding: 1em;
}

.main-header__nav {
  border-top: solid 1px #ccc;
  margin: 1em -1em;
}

.main-header__nav a {
  display: block;
  padding: 0.5em 1em;
  border-bottom: solid 1px #ddd;
}

.main-header__nav a:hover,
.main-header__nav a:focus {
  color: #eee;
  background: #da0d25;
}

@media (max-width: 800px) {
  body { padding: 0; }

  .main-header {
    position: relative;
    width: 100%;
  }

  .main-header__nav a { display: inline-block; border: none; }
}

.intro {
  padding: 4em 2em;
}

.demo {
  padding: 6em 2em;
}

.demo h2 {
  text-align: center;
  font-size: 22px;
  margin-bottom: 1em;
}

.demo .flipster {
  margin: 0 -2em;
}

.code {
  display: block;
  background: #eee;
  padding: 1em;
  border-radius: 1em;
  margin: 2em auto;
  max-width: 30em;
  font-size: 0.8em;
  width: fit-content;
  white-space: pre-wrap;
}

.button {
  display: inline-block;
  padding: 5px 10px;
  margin: 0;
  background-color: #da0d25;
  background-position: center center;
  background-repeat: no-repeat;
  color: #FFF;
  text-shadow: none;
  vertical-align: middle;
  cursor: pointer;
  border: 0;
  transition: all 300ms ease;
}

.button:hover,
.button:focus {
  color: #7a0715;
  background: #f22840;
}