* {
  box-sizing: border-box;
}

body {
  font-family:
    -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  max-width: 900px;
  margin: 0 auto;
  padding: 20px;
  color: #333;
  line-height: 1.6;
}

header {
  border-bottom: 2px solid #e67e22;
  padding-bottom: 15px;
  margin-bottom: 25px;
}

nav a {
  margin-right: 15px;
  text-decoration: none;
  color: #e67e22;
  font-weight: 500;
}

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

nav span {
  margin-right: 15px;
  color: #666;
}

main {
  min-height: 300px;
}

h1 {
  color: #2c3e50;
}

footer {
  margin-top: 40px;
  padding-top: 15px;
  border-top: 1px solid #eee;
  color: #888;
  font-size: 0.9em;
}

.flash {
  padding: 12px 16px;
  margin-bottom: 15px;
  border-radius: 4px;
}

.flash-success {
  background: #d4edda;
  color: #155724;
  border: 1px solid #c3e6cb;
}

.flash-error {
  background: #f8d7da;
  color: #721c24;
  border: 1px solid #f5c6cb;
}

.flash-info {
  background: #d1ecf1;
  color: #0c5460;
  border: 1px solid #bee5eb;
}