/* navbar.css */
header {
  background: #1b2838;
  color: white;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 2rem;
  position: relative;
  z-index: 10;
  width: 100%;
  margin: 0;
  box-sizing: border-box;
}
.logo {
  display: inline-block;
  font-size: 2rem;
  font-weight: bold;
  letter-spacing: 2px;
  color: white;
  background: none;
  border: none;
  text-decoration: none;
  cursor: pointer;
  margin-right: 2rem;
  transition: filter 0.2s;
}
.logo:hover {
  filter: brightness(1.3);
}
.logo-center {
  display: none;
}
.burger {
  display: none;
}
nav ul {
  list-style: none;
  display: flex;
  gap: 2rem;
  margin: 0;
  padding: 0;
}
nav a {
  color: white;
  text-decoration: none;
  font-weight: 500;
  font-size: 1.05rem;
  transition: color 0.2s, font-size 0.3s;
}
nav a:hover {
  color: #ffa500;
}
/* Sidebar styles */
.sidebar {
  position: fixed;
  top: 0; left: 0;
  height: 100%;
  width: 220px;
  background: #1b2838;
  box-shadow: 3px 0 15px rgba(0,0,0,0.25);
  transform: translateX(-100%);
  transition: transform 0.32s cubic-bezier(.42,0,.58,1);
  z-index: 1002;
  padding-top: 2.6rem;
}
.sidebar.open {
  transform: translateX(0);
}
.sidebar .close-btn {
  position: absolute;
  left: 7px;
  top: 7px;
  background: none;
  color: #fff;
  border: none;
  font-size: 2rem;
  cursor: pointer;
  z-index: 1003;
}
.sidebar ul {
  list-style: none;
  padding: 0;
  margin-top: 2.2rem;
}
.sidebar ul li a {
  display: block;
  color: white;
  text-decoration: none;
  padding: 1rem 1.5rem;
  font-size: 1.1rem;
  border-bottom: 1px solid #273445;
  transition: background 0.15s;
}
.sidebar ul li a:hover {
  background: #ffa500;
  color: #1b2838;
}
.sidebar-overlay {
  display: none;
  position: fixed; left:0; top:0;
  width:100vw; height:100vh;
  background: rgba(0,0,0,0.28);
  z-index: 1001;
  transition: opacity 0.2s;
  opacity: 0;
}
.sidebar-overlay.show {
  display: block;
  opacity: 1;
}
@media (max-width: 600px) {
  header {
    justify-content: center;
    align-items: center;
    padding: 0.7rem 0.3rem;
    position: relative;
  }
  .burger {
    display: inline-block;
    z-index: 1004;
    font-size: 2rem;
    background: none;
    border: none;
    color: white;
    padding: 0 1rem 0 0;
    cursor: pointer;
    margin-right: 0;
  }
  .logo {
    display: none;
  }
  .logo-center {
    display: block;
    font-size: 1.35rem;
    font-weight: bold;
    letter-spacing: 2px;
    color: white;
    flex: 1;
    text-align: center;
  }
  nav ul {
    display: none;
  }
}