* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: Arial, sans-serif;
  background-color: #f5f5f5;
  color: #333;
  height: 100vh;
}

.app-layout {
  display: flex;
  height: 100vh;
}

.sidebar {
  width: 260px;
  background-color: #2c3e50;
  color: white;
  display: flex;
  flex-direction: column;
  padding: 1.5rem 1rem;
  box-shadow: 2px 0 8px rgba(0, 0, 0, 0.15);
}

.logo h2 {
  font-size: 1.25rem;
  margin-bottom: 2rem;
  text-align: center;
  color: #ecf0f1;
}

.menu {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.sidebar-footer {
  margin-top: auto;
  padding-top: 1rem;
  border-top: 1px solid #34495e;
}

.menu-btn {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  width: 100%;
  padding: 0.85rem 1rem;
  font-size: 1rem;
  color: #bdc3c7;
  background: transparent;
  border: none;
  border-radius: 6px;
  cursor: pointer;
  text-align: left;
  transition: background-color 0.2s, color 0.2s;
}

.menu-btn:hover {
  background-color: #34495e;
  color: #ffffff;
}

.menu-btn.active {
  background-color: #1abc9c;
  color: #ffffff;
  font-weight: bold;
}

.menu-btn .icon {
  font-size: 1.25rem;
}

.main-content {
  flex: 1;
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

.top-bar {
  background-color: #ffffff;
  padding: 1.5rem 2rem;
  border-bottom: 1px solid #e0e0e0;
  box-shadow: 0 1px 4px rgba(0, 0, 0, 0.05);
}

.top-bar h1 {
  color: #2c3e50;
  font-size: 1.5rem;
}

.section {
  display: none;
  flex: 1;
  padding: 2rem;
  overflow-y: auto;
}

.section.active {
  display: block;
}

.section p {
  color: #666;
  font-size: 1.1rem;
}