body {
  margin: 0;
  font-family: Georgia, "Times New Roman", serif;
  background-color: #f6f4ef;
  color: #2b2b2b;
  line-height: 1.6;
}

.container {
  max-width: 900px;
  margin: auto;
  padding: 20px;
}

header {
  background-color: #2f3e46;
  color: #ffffff;
}

header h1 {
  margin: 0;
}

nav ul {
  list-style: none;
  padding: 0;
  display: flex;
  gap: 15px;
}

nav a {
  color: #ffffff;
  text-decoration: none;
}

nav a.active {
  text-decoration: underline;
}

.hero {
  text-align: center;
  margin: 40px 0;
}

.hero h2 {
  font-size: 2.2em;
}

.hero h3 {
  font-weight: normal;
}

.course {
  margin-bottom: 30px;
}

blockquote {
  font-style: italic;
  border-left: 4px solid #2f3e46;
  padding-left: 15px;
}

.video-block {
  margin-bottom: 40px; /* space between videos */
}

.video-block h3 {
  margin-bottom: 15px; /* space between heading and video */
  font-size: 1.5em;
  font-weight: bold;
}

.video-wrapper {
  position: relative;
  padding-bottom: 56.25%; /* 16:9 aspect ratio */
  height: 0;
  overflow: hidden; /* prevents overlap */
}

.video-wrapper iframe {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
}

footer {
  background-color: #e0ded8;
  margin-top: 40px;
}