body {
  font-family: Arial, sans-serif;
  margin: 0;
  padding: 0;
  background: #f4f4f4;
  color: #333;
}

header {
  background: #333;
  color: #fff;
  padding: 10px 0;
}

header nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

header .logo {
  font-size: 24px;
  font-weight: bold;
}

header ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
}

header ul li {
  margin-left: 20px;
}

header ul li a {
  color: #fff;
  text-decoration: none;
  padding: 5px 10px;
}

header ul li a:hover {
  background: #555;
  border-radius: 5px;
}

.section {
  padding: 60px 0;
  text-align: center;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

.section h2 {
  margin-bottom: 20px;
  font-size: 32px;
}

.section p {
  font-size: 18px;
}

.btn {
  display: inline-block;
  background: #333;
  color: #fff;
  padding: 10px 20px;
  text-decoration: none;
  border-radius: 5px;
  margin-top: 20px;
}

.btn:hover {
  background: #555;
}

.features {
  display: flex;
  justify-content: space-around;
  flex-wrap: wrap;
}

.feature {
  background: #fff;
  padding: 20px;
  margin: 10px;
  flex: 1 1 calc(25% - 40px);
  box-shadow: 0 0 10px rgba(0,0,0,0.1);
}

.feature h3 {
  margin-top: 0;
}

.commands {
  list-style: none;
  padding: 0;
}

.commands li {
  background: #fff;
  padding: 10px;
  margin: 5px 0;
  border-radius: 5px;
  box-shadow: 0 0 10px rgba(0,0,0,0.1);
}

footer {
  background: #333;
  color: #fff;
  text-align: center;
  padding: 10px 0;
}