:root {
    --primary: #6366f1;
    --primary-hover: #4f46e5;
    --secondary: #64748b;
    --dark: #0f172a;
    --light: #f8fafc;
    --success: #10b981;
    --danger: #ef4444;
    --warning: #f59e0b;
    --white: #ffffff;
    --gray-100: #f1f5f9;
    --gray-200: #e2e8f0;
    --gray-300: #cbd5e1;
    --shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --radius: 12px;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Inter', -apple-system, sans-serif;
}

body {
    background-color: var(--gray-100);
    color: var(--dark);
    line-height: 1.5;
}

/* Glassmorphism utility */
.glass {
    background: rgba(255, 255, 255, 0.7);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: var(--radius);
}

/* Login Page Styles */
.login-container {
    height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, #6366f1 0%, #a855f7 100%);
}

.login-card {
    width: 100%;
    max-width: 400px;
    padding: 2.5rem;
    background: var(--white);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    animation: fadeIn 0.5s ease-out;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

.login-header {
    text-align: center;
    margin-bottom: 2rem;
}

.login-header h1 {
    font-size: 1.875rem;
    font-weight: 700;
    color: var(--dark);
    margin-bottom: 0.5rem;
}

.form-group {
    margin-bottom: 1.5rem;
}

.form-group label {
    display: block;
    font-size: 0.875rem;
    font-weight: 500;
    margin-bottom: 0.5rem;
}

.form-control {
    width: 100%;
    padding: 0.75rem 1rem;
    border: 1px solid var(--gray-300);
    border-radius: 8px;
    outline: none;
    transition: border-color 0.2s;
}

.form-control:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.75rem 1.5rem;
    font-weight: 600;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.2s;
    border: none;
    width: 100%;
}

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

.btn-primary:hover {
    background-color: var(--primary-hover);
    transform: translateY(-1px);
}

/* Dashboard Styles */
.dashboard-layout {
    display: grid;
    grid-template-columns: 260px 1fr;
    min-height: 100vh;
}

.sidebar {
    background-color: var(--dark);
    color: var(--white);
    padding: 2rem 1.5rem;
    position: sticky;
    top: 0;
    height: 100vh;
}

.nav-link {
    display: flex;
    align-items: center;
    padding: 0.75rem 1rem;
    color: var(--gray-300);
    text-decoration: none;
    border-radius: 8px;
    margin-bottom: 0.5rem;
    transition: all 0.2s;
}

.nav-link:hover, .nav-link.active {
    background-color: rgba(255, 255, 255, 0.1);
    color: var(--white);
}

.main-content {
    padding: 2rem;
    overflow-y: auto;
}

.header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 2rem;
}

.card {
    background: var(--white);
    padding: 1.5rem;
    border-radius: var(--radius);
    box-shadow: 0 1px 3px rgba(0,0,0,0.1);
    margin-bottom: 1.5rem;
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.stat-card {
    padding: 1.5rem;
    border-radius: var(--radius);
    background: var(--white);
    box-shadow: 0 1px 3px rgba(0,0,0,0.1);
    display: flex;
    flex-direction: column;
}

.stat-label {
    color: var(--secondary);
    font-size: 0.875rem;
    font-weight: 500;
}

.stat-value {
    font-size: 1.5rem;
    font-weight: 700;
    margin-top: 0.25rem;
}

/* Attendance Controls */
.attendance-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
}

#map-container {
    height: 300px;
    background: var(--gray-200);
    border-radius: var(--radius);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--secondary);
}

.time-display {
    font-size: 3rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 1rem;
    color: var(--primary);
}

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

table {
    width: 100%;
    border-collapse: collapse;
}

th {
    text-align: left;
    padding: 1rem;
    background: var(--gray-100);
    font-weight: 600;
    color: var(--secondary);
}

td {
    padding: 1rem;
    border-bottom: 1px solid var(--gray-200);
}

@media (max-width: 768px) {
    .dashboard-layout {
        grid-template-columns: 1fr;
    }
    .sidebar {
        display: none; /* In real app, implement a hamburger menu */
    }
    .attendance-grid {
        grid-template-columns: 1fr;
    }
}