/* Top Navigation */
.topnav {
  background-color: #2c3e50;
  overflow: hidden;
  display: flex;
  justify-content: center;
  padding: 0.5rem 0;
  position: sticky;
  top: 0;
  z-index: 1000;
  transition: all 0.3s ease;
  flex-wrap: wrap;
}

.topnav a {
  color: white;
  text-align: center;
  padding: 0.75rem 1.25rem;
  text-decoration: none;
  font-size: 1rem;
  transition: all 0.3s ease;
  border-radius: 6px;
  margin: 0 0.25rem;
}

.topnav a:hover {
  background-color: #34495e;
  color: #f1c40f;
}

/* Active nav link */
.topnav a.active {
  background-color: #f1c40f;
  color: #2c3e50;
  font-weight: bold;
}

/* Animate nav link click */
.topnav a:active {
  transform: scale(0.95);
  transition: transform 0.1s ease;
}

/* Hamburger button */
.nav-toggle {
  display: none;
  background: none;
  border: none;
  color: #fff;
  font-size: 2rem;
  cursor: pointer;
  margin-left: auto;
}

@media (max-width: 600px) {
  .topnav {
    flex-direction: column;
    align-items: flex-start;
    position: relative;
    padding: 0.5rem 1rem;
  }

  .nav-toggle {
    display: block;
    margin: 0.25rem 1rem;
  }

  /* Collapsed links */
  .topnav a {
    display: block;
    width: 100%;
    margin: 0;
    padding: 0;             /* no space when collapsed */
    max-height: 0;
    overflow: hidden;
    opacity: 0;
    transition: max-height 0.3s ease, opacity 0.3s ease, padding 0.3s ease;
  }

  /* Open links */
  .topnav a.show {
    padding: 0.75rem 1rem; /* restore padding */
    max-height: 100px;     /* adjust for link height */
    opacity: 1;
  }
}