:root {
  /* Color Palette - Modern Corporate Professional */
  --primary: #0f172a;
  --primary-light: #1e293b;
  --accent: #3b82f6;
  --accent-hover: #2563eb;
  --success: #10b981;
  --warning: #f59e0b;
  --danger: #ef4444;
  --bg-main: #f8fafc;
  --bg-card: #ffffff;
  --border: #e2e8f0;
  --text-main: #1e293b;
  --text-muted: #64748b;
  --sidebar-w: 260px;
  
  /* Shadows */
  --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
  --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
  --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);

  /* Radius */
  --radius: 12px;
}

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

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  background-color: var(--bg-main);
  color: var(--text-main);
  line-height: 1.5;
  min-height: 100vh;
  display: flex;
}

/* Layout */
.app-container {
  display: flex;
  width: 100%;
}

.sidebar {
  width: var(--sidebar-w);
  background: var(--primary);
  color: white;
  height: 100vh;
  position: fixed;
  left: 0;
  top: 0;
  display: flex;
  flex-direction: column;
  z-index: 100;
}

.main-content {
  margin-left: var(--sidebar-w);
  flex: 1;
  padding: 2rem;
  min-height: 100vh;
}

/* Sidebar Styling */
.sidebar-header {
  padding: 2rem 1.5rem;
  font-size: 1.25rem;
  font-weight: 700;
  display: flex;
  align-items: center;
  gap: 0.75rem;
  border-bottom: 1px solid rgba(255,255,255,0.1);
}

.nav-list {
  list-style: none;
  padding: 1.5rem 0.75rem;
  flex: 1;
}

.nav-item {
  margin-bottom: 0.5rem;
}

.nav-link {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.75rem 1rem;
  color: #94a3b8;
  text-decoration: none;
  border-radius: var(--radius);
  transition: all 0.2s;
}

.nav-link:hover {
  background: rgba(255,255,255,0.05);
  color: white;
}

.nav-link.active {
  background: var(--accent);
  color: white;
}

.sidebar-footer {
  padding: 1.5rem;
  border-top: 1px solid rgba(255,255,255,0.1);
}

/* Cards & Components */
.card {
  background: var(--bg-card);
  border-radius: var(--radius);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
  padding: 1.5rem;
  margin-bottom: 1.5rem;
}

.grid {
  display: grid;
  gap: 1.5rem;
}

.grid-cols-4 { grid-template-columns: repeat(4, 1fr); }
.grid-cols-3 { grid-template-columns: repeat(3, 1fr); }
.grid-cols-2 { grid-template-columns: repeat(2, 1fr); }

/* Typography */
h1 { font-size: 1.875rem; font-weight: 700; margin-bottom: 0.5rem; }
h2 { font-size: 1.25rem; font-weight: 600; margin-bottom: 1rem; }
.text-muted { color: var(--text-muted); font-size: 0.875rem; }

/* Dashboard Widgets */
.stat-card {
  padding: 1.5rem;
  border-radius: var(--radius);
  background: var(--bg-card);
  border: 1px solid var(--border);
  display: flex;
  flex-direction: column;
}

.stat-label { font-size: 0.875rem; color: var(--text-muted); margin-bottom: 0.5rem; }
.stat-value { font-size: 1.5rem; font-weight: 700; }

/* Tables */
.table-container {
  overflow-x: auto;
}

table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
}

th {
  background: #f1f5f9;
  padding: 0.75rem 1rem;
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-muted);
  border-bottom: 1px solid var(--border);
}

td {
  padding: 1rem;
  border-bottom: 1px solid var(--border);
  font-size: 0.875rem;
}

/* Badges */
.badge {
  padding: 0.25rem 0.625rem;
  border-radius: 9999px;
  font-size: 0.75rem;
  font-weight: 500;
}

.badge-pending { background: #fef3c7; color: #92400e; }
.badge-approved { background: #dcfce7; color: #166534; }
.badge-rejected { background: #fee2e2; color: #991b1b; }

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.625rem 1.25rem;
  border-radius: 8px;
  font-weight: 600;
  font-size: 0.875rem;
  cursor: pointer;
  border: none;
  transition: all 0.2s;
  text-decoration: none;
}

.btn-primary { background: var(--accent); color: white; }
.btn-primary:hover { background: var(--accent-hover); }

.btn-outline { background: transparent; border: 1px solid var(--border); color: var(--text-main); }
.btn-outline:hover { background: #f1f5f9; }

/* Form Elements */
.form-group { margin-bottom: 1.25rem; }
.label { display: block; font-size: 0.875rem; font-weight: 500; margin-bottom: 0.5rem; }
.input {
  width: 100%;
  padding: 0.75rem;
  border: 1px solid var(--border);
  border-radius: 8px;
  font-size: 0.875rem;
}

.input:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}

/* Icons Placeholder */
.icon {
  width: 20px;
  height: 20px;
  flex-shrink: 0;
}

/* Profile Section */
.profile-pill {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.5rem;
  border-radius: 9999px;
  background: #f1f5f9;
}

.avatar {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background: var(--accent);
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-weight: 600;
  font-size: 0.75rem;
}

/* Responsive */
@media (max-width: 1024px) {
  .sidebar { width: 80px; }
  .sidebar-header span, .nav-link span, .sidebar-footer span { display: none; }
  .main-content { margin-left: 80px; }
  .grid-cols-4 { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 640px) {
  .grid-cols-4, .grid-cols-3, .grid-cols-2 { grid-template-columns: 1fr; }
}