:root {
  /* Color Palette - Deep Professional Slate & Electric Indigo */
  --bg-main: #0f172a;
  --bg-card: #1e293b;
  --bg-accent: #334155;
  --text-primary: #f8fafc;
  --text-secondary: #94a3b8;
  --accent-color: #6366f1;
  --accent-hover: #818cf8;
  --success: #10b981;
  --warning: #f59e0b;
  --danger: #ef4444;
  --border-color: rgba(255, 255, 255, 0.1);
  
  /* Spacing & Sizing */
  --space-xs: 4px;
  --space-sm: 8px;
  --space-md: 16px;
  --space-lg: 24px;
  --space-xl: 48px;
  --space-2xl: 64px;
  --radius-sm: 6px;
  --radius-md: 12px;
  --radius-lg: 20px;
  
  /* Typography */
  --font-main: 'Plus Jakarta Sans', system-ui, -apple-system, sans-serif;
  --font-mono: 'JetBrains Mono', monospace;
}

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

body {
  background-color: var(--bg-main);
  color: var(--text-primary);
  font-family: var(--font-main);
  line-height: 1.5;
  min-height: 100vh;
  overflow-x: hidden;
}

/* Layout */
.app-container {
  display: flex;
  min-height: 100vh;
}

/* Sidebar */
.sidebar {
  width: 280px;
  background: var(--bg-card);
  border-right: 1px solid var(--border-color);
  padding: var(--space-lg);
  display: flex;
  flex-direction: column;
  gap: var(--space-xl);
  position: sticky;
  top: 0;
  height: 100vh;
}

.logo {
  font-size: 1.5rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  color: var(--accent-color);
}

.nav-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
}

.nav-link {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  padding: var(--space-md);
  text-decoration: none;
  color: var(--text-secondary);
  border-radius: var(--radius-md);
  transition: all 0.2s ease;
}

.nav-link:hover, .nav-link.active {
  background: rgba(99, 102, 241, 0.1);
  color: var(--text-primary);
}

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

/* Main Content */
.main-content {
  flex: 1;
  padding: var(--space-xl);
  max-width: 1400px;
  margin: 0 auto;
  width: 100%;
}

header {
  display: flex;
  justify-content: space-between;
  align-items: flex-end;
  margin-bottom: var(--space-2xl);
}

.header-title h1 {
  font-size: 2.5rem;
  font-weight: 700;
  letter-spacing: -0.04em;
  margin-bottom: var(--space-xs);
}

.header-title p {
  color: var(--text-secondary);
}

/* Stats Grid */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--space-lg);
  margin-bottom: var(--space-2xl);
}

.stat-card {
  background: var(--bg-card);
  padding: var(--space-lg);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-color);
  transition: transform 0.2s ease;
}

.stat-card:hover {
  transform: translateY(-4px);
}

.stat-label {
  color: var(--text-secondary);
  font-size: 0.875rem;
  margin-bottom: var(--space-sm);
  display: block;
}

.stat-value {
  font-size: 2rem;
  font-weight: 700;
  display: block;
}

.stat-trend {
  font-size: 0.75rem;
  margin-top: var(--space-sm);
  display: flex;
  align-items: center;
  gap: 4px;
}

.trend-up { color: var(--success); }
.trend-down { color: var(--danger); }

/* Layout Helpers */
.flex-between { display: flex; justify-content: space-between; align-items: center; }
.flex-end { display: flex; justify-content: flex-end; align-items: flex-end; }
.flex-center { display: flex; align-items: center; }
.gap-sm { gap: var(--space-sm); }
.gap-md { gap: var(--space-md); }
.gap-lg { gap: var(--space-lg); }
.mt-auto { margin-top: auto; }
.font-mono { font-family: var(--font-mono); }

/* Components */
.filter-tabs { display: flex; gap: var(--space-sm); }
.btn-sm { padding: 6px 12px; font-size: 0.75rem; }
.pagination { display: flex; gap: var(--space-sm); }
.progress-bar { width: 100px; height: 6px; background: var(--bg-accent); border-radius: 3px; overflow: hidden; }
.progress-fill { height: 100%; }
.dot { width: 6px; height: 6px; border-radius: 50%; }

/* Table Section */
.section-card {
  background: var(--bg-card);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-color);
  overflow: hidden;
}

.section-header {
  padding: var(--space-lg);
  border-bottom: 1px solid var(--border-color);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.table-container {
  overflow-x: auto;
}

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

th {
  padding: var(--space-lg);
  color: var(--text-secondary);
  font-weight: 600;
  font-size: 0.875rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  background: rgba(0,0,0,0.1);
}

td {
  padding: var(--space-lg);
  border-bottom: 1px solid var(--border-color);
}

tr:last-child td {
  border-bottom: none;
}

.user-cell {
  display: flex;
  align-items: center;
  gap: var(--space-md);
}

.avatar {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: var(--bg-accent);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  color: var(--accent-color);
  flex-shrink: 0;
}

.status-badge {
  padding: 6px 12px;
  border-radius: 100px;
  font-size: 0.75rem;
  font-weight: 600;
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.status-present { background: rgba(16, 185, 129, 0.1); color: var(--success); }
.status-absent { background: rgba(239, 68, 68, 0.1); color: var(--danger); }
.status-late { background: rgba(245, 158, 11, 0.1); color: var(--warning); }
.status-remote { background: rgba(99, 102, 241, 0.1); color: var(--accent-color); }

/* Form Elements */
.search-bar {
  background: var(--bg-accent);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 10px 16px;
  color: var(--text-primary);
  width: 300px;
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.search-bar input {
  background: none;
  border: none;
  color: inherit;
  width: 100%;
  outline: none;
}

.btn {
  padding: 10px 20px;
  border-radius: var(--radius-md);
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s;
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
  text-decoration: none;
}

.btn-primary {
  background: var(--accent-color);
  color: white;
  border: none;
}

.btn-primary:hover {
  background: var(--accent-hover);
  box-shadow: 0 0 20px rgba(99, 102, 241, 0.3);
}

.btn-outline {
  background: transparent;
  border: 1px solid var(--border-color);
  color: var(--text-primary);
}

.btn-outline:hover {
  background: var(--bg-accent);
}

/* Utility */
.text-bold { font-weight: 700; }
.text-muted { color: var(--text-secondary); font-size: 0.875rem; }

/* Placeholders */
.placeholder-avatar {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--accent-color), #4f46e5);
}