body {
  margin: 0;
  font-family: Arial, sans-serif;
  background: #0f172a;
  color: white;
}

header {
  text-align: center;
  padding: 40px;
  background: #111827;
}

nav {
  display: flex;
  justify-content: center;
  gap: 10px;
  background: #1f2937;
  padding: 10px;
}

nav button {
  padding: 10px 15px;
  border: none;
  cursor: pointer;
  background: #374151;
  color: white;
  border-radius: 6px;
}

.tab { display: none; padding: 30px; }
.tab.active { display: block; }

.card {
  background: #1e293b;
  padding: 20px;
  margin: 15px 0;
  border-radius: 10px;
}

#chatbot {
  position: fixed;
  bottom: 20px;
  right: 20px;
  width: 280px;
  background: #111827;
  border: 1px solid #374151;
  border-radius: 10px;
  overflow: hidden;
}

#chat-header {
  background: #2563eb;
  padding: 10px;
  font-weight: bold;
}

#chat-box {
  height: 200px;
  overflow-y: auto;
  padding: 10px;
  font-size: 14px;
}

#chat-input { display: flex; }

#chat-input input {
  flex: 1;
  padding: 8px;
  border: none;
}

#chat-input button {
  background: #2563eb;
  color: white;
  border: none;
  padding: 8px;
}