.navbar-nav .nav-link.active {
  font-weight: bold;
  color: #0d6efd !important;
}
html, body {
  height: 100%;
  margin: 0;
}

body {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

main {
  flex: 1 0 auto; 
}

footer {
  flex-shrink: 0;
}