body {
  font-family: system-ui, Arial, sans-serif;
  background: #f7fafc;
  margin: 0;
  color: #232629;
}

header, nav, footer {
  padding: 16px;
  background: #ffffff;
  margin-bottom: 12px;
}

header {
  border-bottom: 1px solid #e0e6ed;
}

nav ul {
  list-style: none;
  display: flex;
  gap: 16px;
  padding: 0;
  margin: 0;
}

nav a {
  color: #0b5fff;
  text-decoration: none;
  font-weight: bold;
}
nav a:hover {
  text-decoration: underline;
}

main {
  display: flex;
  gap: 24px;
  max-width: 900px;
  margin: 0 auto;
  padding: 16px;
  background: #fff;
  border-radius: 8px;
}

article {
  flex: 2;
}
aside {
  flex: 1;
  background: #f0f4f8;
  border-radius: 8px;
  padding: 16px;
}

footer {
  text-align: center;
  color: #888;
  font-size: 0.95rem;
}