/* ------------------------------
   Global styles
--------------------------------*/

body {
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI",
               Roboto, Helvetica, Arial, sans-serif;
  margin: 0;
  padding: 0;
  background: #f5f7fa;
  color: #333;
  line-height: 1.6;
}

img, video {
  max-width: 100%;
  height: auto;
  display: block;
}

/* ------------------------------
   Header + Navigation
--------------------------------*/

header {
  background: #1e90ff;
  color: white;
  padding: 1.2rem;
  text-align: center;
  box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

header h1 {
  margin: 0 0 0.5rem 0;
  font-size: 1.8rem;
}

nav a {
  color: white;
  text-decoration: none;
  margin: 0 0.8rem;
  font-weight: 600;
}

nav a:hover {
  text-decoration: underline;
}

/* ------------------------------
   Main content
--------------------------------*/

main {
  max-width: 900px;
  margin: 2rem auto;
  padding: 0 1rem;
}

h2 {
  margin-top: 2rem;
  color: #1e90ff;
}

section {
  margin-bottom: 2rem;
}

/* ------------------------------
   Lists
--------------------------------*/

ul {
  padding-left: 1.2rem;
}

ul li {
  margin-bottom: 0.6rem;
}

/* ------------------------------
   Footer
--------------------------------*/

footer {
  text-align: center;
  padding: 1.5rem;
  margin-top: 3rem;
  color: #666;
  font-size: 0.9rem;
}

/* ------------------------------
   Utility classes (optional)
--------------------------------*/

.center {
  text-align: center;
}

.card {
  background: white;
  padding: 1.2rem;
  border-radius: 8px;
  box-shadow: 0 2px 4px rgba(0,0,0,0.08);
  margin-bottom: 1.5rem;
}