/* Reset và CSS cơ bản */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body { 
  background: #f7fafd; 
  font-family: 'Segoe UI', Arial, sans-serif; 
  min-height: 100vh;
}

/* Sidebar styles */
.sidebar { 
  background: radial-gradient(120% 70% at -10% -15%, #eaf8ff 0 45%, transparent 46%), radial-gradient(90% 65% at 115% 110%, #e9fff3 0 50%, transparent 51%), linear-gradient(180deg, #ffffff 0%, #f7fbff 40%, #fafff7 100%); 
  border-right: 1px solid #e0e0e0; 
  min-height: 100vh; 
  padding: 0; 
  position: fixed;
  top: 0;
  left: 0;
  width: 250px;
  z-index: 1000;
  overflow-y: auto;
  overflow-x: hidden;
}

/* Sidebar scrollbar styling */
.sidebar::-webkit-scrollbar {
  width: 6px;
}

.sidebar::-webkit-scrollbar-track {
  background: rgba(0, 0, 0, 0.1);
  border-radius: 3px;
}

.sidebar::-webkit-scrollbar-thumb {
  background: rgba(0, 0, 0, 0.3);
  border-radius: 3px;
}

.sidebar::-webkit-scrollbar-thumb:hover {
  background: rgba(0, 0, 0, 0.5);
}

.sidebar .avatar { 
  width: 56px; 
  height: 56px; 
  object-fit: cover; 
  border-radius: 50%; 
  border: 2px solid #1976d2; 
  margin-bottom: 8px; 
}

.sidebar .sidebar-user { 
  text-align: center; 
  padding: 32px 0 16px 0; 
}

.sidebar .sidebar-user .name { 
  font-weight: 700; 
  color: #155CA2; 
  font-size: 14px;
  line-height: 1.2;
}

.sidebar .sidebar-user .role { 
  color: #155CA2; 
  font-size: 15px; 
}

.sidebar .nav-link { 
  color: #155CA2; 
  font-weight: 500; 
  border-radius: 8px; 
  margin-bottom: 2px; 
  padding: 12px 16px;
  text-decoration: none;
  display: block;
  transition: all 0.3s ease;
}

.sidebar .nav-link:hover { 
  background: #e3f0fa; 
  color: #155CA2; 
}

.sidebar .nav-link.active, 
.sidebar .nav-link:focus { 
  background: #e3f0fa; 
  color: #155CA2; 
  font-weight: 700; 
}

.sidebar .nav-link i { 
  margin-right: 8px; 
}

.sidebar .submenu { 
  padding-left: 24px; 
  background: #f8f9fa;
  border-radius: 8px;
  margin: 4px 16px;
}

.sidebar .submenu .nav-link {
  padding: 8px 16px;
  font-size: 14px;
}

.sidebar .logout-link { 
  color: #155CA2; 
  font-weight: 600; 
  margin-top: 24px; 
  display: flex; 
  align-items: center; 
  gap: 8px; 
  padding: 12px 16px;
  text-decoration: none;
  cursor: pointer;
}

.sidebar .logout-link:hover { 
  color: #e53935; 
}

/* Main content */
.main-content { 
  padding: 0 32px 0 282px; 
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

.header-bar { 
  background: #fff; 
  border-bottom: 1px solid #e0e0e0; 
  padding: 20px 0px 10px 20px;
  margin-bottom: 18px; 
  border-radius: 1.2rem;
}

.breadcrumb { 
  background: none; 
  padding: 0; 
  margin-bottom: 0; 
  font-size: 1.1rem; 
}

.breadcrumb-item+.breadcrumb-item::before { 
  content: '>'; 
  color: #1976d2; 
}

.page-title { 
  font-weight: 900; 
  color: #155CA2; 
  font-size: 2rem; 
  margin-bottom: 0; 
}

/* Footer */
.footer-bar { 
  background: #fff; 
  border-top: 1px solid #e0e0e0; 
  color: #155CA2; 
  font-size: 15px; 
  padding: 10px 32px 8px 32px; 
  display: flex; 
  justify-content: space-between; 
  align-items: center; 
  margin-top: auto;
}

.footer-bar .contact { 
  display: flex; 
  gap: 18px; 
  align-items: center; 
}

.footer-bar .help-link { 
  color: #155CA2; 
  text-decoration: underline; 
  font-weight: 500; 
}

/* Content area */
.content-area {
  flex: 1;
  padding: 20px 0;
}

/* Responsive */
@media (max-width: 900px) {
  .sidebar { 
    min-width: 100px; 
    width: 200px;
  }
  .main-content { 
    padding: 0 8px 0 208px; 
  }
  .footer-bar { 
    padding: 10px 8px 8px 8px; 
  }
}

@media (max-width: 768px) {
  .sidebar {
    transform: translateX(-100%);
    transition: transform 0.3s ease;
  }
  .sidebar.show {
    transform: translateX(0);
  }
  .main-content {
    padding: 0 8px;
  }
}

/* Loading states */
.loading {
  display: flex;
  justify-content: center;
  align-items: center;
  height: 200px;
  color: #155CA2;
}

/* Error states */
.error-message {
  background: #ffebee;
  color: #c62828;
  padding: 16px;
  border-radius: 8px;
  margin: 16px 0;
  border-left: 4px solid #c62828;
}

/* Success states */
.success-message {
  background: #e8f5e8;
  color: #2e7d32;
  padding: 16px;
  border-radius: 8px;
  margin: 16px 0;
  border-left: 4px solid #2e7d32;
}

/* Utility classes */
.text-center { text-align: center; }
.mt-3 { margin-top: 1rem; }
.mt-5 { margin-top: 3rem; }
.fw-bold { font-weight: bold; }
.lead { font-size: 1.25rem; font-weight: 300; }