body {
  margin: 0; 
  background: #b3afaf; /* Thêm bg nhẹ nếu có */
  font-family: Arial, Helvetica, sans-serif;
  font-size: 15px;
  color: #3d2101;
}
.topbar {
  background: #444;
  color: #fff;
  font-size: 13px;
  text-align: center;
  padding: 4px 0;
  letter-spacing: 0.5px;
}
.container {
  max-width: 640px;
  margin: 18px auto 0 auto;
  background: #ffe2c5;
  border-radius: 10px 10px 8px 8px;
  box-shadow: 0 6px 30px #0001;
  padding-bottom: 12px;
  border: 1.5px solid #c48337;
  min-height: 90vh;
}
.logo-bar {
  text-align: center;
  padding: 14px 0 10px 0;
}
.logo-bar img {
  max-height: 60px;
  filter: drop-shadow(1px 3px 4px #8e572e40);
}
nav {
  display: flex;
  background: #cf883b;
  border-radius: 7px;
  overflow: hidden;
  margin: 0 16px 12px 16px;
  box-shadow: 0 1px 4px #f6c08a30;
}
nav a {
  flex: 1;
  text-align: center;
  padding: 12px 0;
  color: #fff8f0;
  font-weight: bold;
  text-decoration: none;
  font-size: 16px;
  transition: 0.18s;
  border-right: 1px solid #e6b17666;
  background: none;
}
nav a:last-child { border-right: none; }
nav a.active, nav a:hover {
  background: #d4a25f;
  color: #6b3400;
  text-shadow: 0 1px 0 #fff7;
}

.footer {
  color: #664900;
  text-align: center;
  padding: 12px 16px 3px 16px;
  font-size: 14px;
  margin-top: 6px;
}
@media (max-width: 660px) {
  .container { border-radius: 0; box-shadow: none;}
}