:root {
    --primary-color: #4F46E5;
    --primary-dark: #4338CA;
    --primary-light: #6366F1;
    --secondary-color: #10B981;
    --danger-color: #EF4444;
    --warning-color: #FCD34D;
    --info-color: #3B82F6;
    --dark-color: #1F2937;
    --light-bg: #F9FAFB;
    --border-color: #E5E7EB;
    --text-primary: #111827;
    --text-secondary: #6B7280;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
}

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background: var(--light-bg);
    color: var(--text-primary);
    line-height: 1.6;
}

/* Modern Navbar */
.navbar {
    background: var(--primary-color) !important;
    box-shadow: var(--shadow-md);
    padding: 1rem 0 !important;
    border: none;
}

.navbar-brand {
    font-size: 1.5rem;
    font-weight: 700;
    letter-spacing: -0.02em;
    color: white !important;
    transition: transform 0.2s ease;
}

.navbar-brand:hover {
    transform: translateY(-2px);
}

.nav-link {
    color: rgba(255, 255, 255, 0.9) !important;
    font-weight: 500;
    padding: 0.5rem 1rem !important;
    border-radius: var(--radius-md);
    transition: all 0.3s ease;
}

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

/* Modern Cards */
.card {
    border: none;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
    transition: all 0.3s ease;
    background: white;
    overflow: hidden;
}

.card:hover {
    box-shadow: var(--shadow-lg);
    transform: translateY(-2px);
}

.card-header {
    background: var(--primary-color);
    color: white;
    border: none;
    padding: 1.25rem 1.5rem;
    font-weight: 600;
}

.card-body {
    padding: 1.5rem;
}

/* Modern Buttons */
.btn {
    border-radius: var(--radius-md);
    font-weight: 500;
    padding: 0.625rem 1.25rem;
    border: none;
    transition: all 0.3s ease;
    box-shadow: var(--shadow-sm);
}

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

.btn-primary:hover {
    background: var(--primary-dark);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.btn-success {
    background: var(--secondary-color);
}

.btn-success:hover {
    background: #059669;
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.btn-warning {
    background: var(--warning-color);
    color: #78350F;
}

.btn-warning:hover {
    background: #FDE047;
    color: #78350F;
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

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

.btn-danger:hover {
    background: #DC2626;
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.btn-light {
    background: white;
    color: var(--primary-color);
    border: 2px solid var(--border-color);
}

.btn-light:hover {
    background: var(--light-bg);
    border-color: var(--primary-color);
    transform: translateY(-2px);
}

/* Modern Forms */
.form-control, .form-select {
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 0.75rem 1rem;
    transition: all 0.3s ease;
    background: white;
}

.form-control:focus, .form-select:focus {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.1);
    outline: none;
}

.form-label {
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
}

/* Modern Alerts */
.alert {
    border: none;
    border-radius: var(--radius-md);
    padding: 1rem 1.25rem;
    box-shadow: var(--shadow-sm);
}

.alert-success {
    background: #D1FAE5;
    color: #065F46;
}

.alert-danger {
    background: #FEE2E2;
    color: #991B1B;
}

.alert-warning {
    background: #FEF3C7;
    color: #92400E;
}

.alert-info {
    background: #DBEAFE;
    color: #1E40AF;
}

/* Modern Tables */
.table {
    background: white;
    border-radius: var(--radius-lg);
    overflow: hidden;
}

.table thead th {
    background: #F3F4F6;
    color: var(--text-primary);
    font-weight: 600;
    border: none;
    padding: 1rem;
}

.table tbody tr {
    transition: all 0.2s ease;
    border-bottom: 1px solid var(--border-color);
}

.table tbody tr:hover {
    background: var(--light-bg);
}

.table tbody td {
    padding: 1rem;
    vertical-align: middle;
}

/* Modern Badges */
.badge {
    border-radius: var(--radius-sm);
    padding: 0.375rem 0.75rem;
    font-weight: 600;
    font-size: 0.75rem;
    letter-spacing: 0.02em;
}

/* Dashboard Stats Cards */
.stats-card {
    background: white;
    border-radius: var(--radius-lg);
    padding: 1.5rem;
    box-shadow: var(--shadow-md);
    transition: all 0.3s ease;
    border-left: 4px solid var(--primary-color);
}

.stats-card:hover {
    box-shadow: var(--shadow-lg);
    transform: translateY(-4px);
}

.stats-card h2 {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--text-primary);
    margin: 0;
}

.stats-card h5 {
    color: var(--text-secondary);
    font-weight: 600;
    margin: 0;
}

/* Auth Pages */
.auth-container {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--primary-color);
    position: relative;
    overflow: hidden;
}

.auth-container::before {
    content: '';
    position: absolute;
    width: 500px;
    height: 500px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 50%;
    top: -250px;
    right: -250px;
}

.auth-container::after {
    content: '';
    position: absolute;
    width: 300px;
    height: 300px;
    background: rgba(255, 255, 255, 0.05);
    border-radius: 50%;
    bottom: -150px;
    left: -150px;
}

.auth-card {
    background: white;
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-xl);
    padding: 2.5rem;
    max-width: 480px;
    width: 90%;
    margin: 2rem auto;
    position: relative;
    z-index: 1;
}

.auth-card h3 {
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
}

/* QR Scanner */
#qr-reader {
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow-md);
}

/* Animations */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.fade-in-up {
    animation: fadeInUp 0.5s ease-out;
}

/* Responsive */
@media (max-width: 768px) {
    .navbar-brand {
        font-size: 1.25rem;
    }
    
    .card-body {
        padding: 1rem;
    }
    
    .auth-card {
        padding: 1.5rem;
        margin: 1rem;
        width: calc(100% - 2rem);
        max-width: 100%;
    }
    
    .stats-card h2 {
        font-size: 2rem;
    }
}

@media (max-width: 576px) {
    .auth-card {
        padding: 1.25rem;
        margin: 0.75rem;
        width: calc(100% - 1.5rem);
    }
    
    .auth-card h3 {
        font-size: 1.5rem;
    }
}

/* Custom Scrollbar */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background: var(--light-bg);
}

::-webkit-scrollbar-thumb {
    background: var(--border-color);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--text-secondary);
}

/* Footer */
footer {
    background: white;
    border-top: 1px solid var(--border-color);
    margin-top: 4rem;
}

/* Dropdown Menu */
.dropdown-menu {
    border: none;
    box-shadow: var(--shadow-lg);
    border-radius: var(--radius-md);
    padding: 0.5rem;
}

.dropdown-item {
    border-radius: var(--radius-sm);
    padding: 0.75rem 1rem;
    transition: all 0.2s ease;
    color: var(--text-primary);
}

.dropdown-item:hover {
    background: var(--light-bg);
    color: var(--primary-color);
}

.dropdown-divider {
    border-color: var(--border-color);
    margin: 0.5rem 0;
}