* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: 'Helvetica Neue', Arial, sans-serif;
}

body {
  background-color: #f3f4f6;
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 100vh;
  color: #333;
}

.content-wrapper {
  width: 100%;
  max-width: 800px;
  padding: 20px;
}

.card {
  background-color: #fff;
  border-radius: 10px;
  box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
  overflow: hidden;
  animation: fadeIn 1s ease;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}

header {
  background-color: #4f46e5;
  color: #fff;
  padding: 20px;
  text-align: center;
}

header h1 {
  font-size: 1.8em;
  font-weight: bold;
}

.subtitle {
  font-size: 1em;
  color: #c3c8e2;
}

.navigation {
  display: flex;
  justify-content: space-around;
  padding: 15px;
  background-color: #eef2ff;
}

.navigation a {
  text-decoration: none;
  color: #4f46e5;
  font-weight: 600;
  transition: color 0.2s ease;
}

.navigation a:hover {
  color: #2b2d42;
}

main {
  padding: 25px;
}

main h2 {
  font-size: 1.5em;
  color: #4f46e5;
  border-bottom: 2px solid #edf2ff;
  padding-bottom: 8px;
  margin-top: 20px;
}

main h3 {
  font-size: 1.2em;
  color: #333;
  margin-top: 15px;
  font-weight: 600;
}

p, ul, li {
  line-height: 1.6;
  color: #444;
  margin-top: 12px;
}

ul {
  padding-left: 20px;
}

li {
  list-style-type: disc;
}

strong {
  color: #333;
}

@media (max-width: 768px) {
  .content-wrapper {
    padding: 10px;
  }

  header h1 {
    font-size: 1.5em;
  }

  .navigation {
    flex-direction: column;
    align-items: center;
  }
}