:root {
    /* Color Palette */
    --primary-gradient: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --secondary-gradient: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
    --success-gradient: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%);
    --warning-gradient: linear-gradient(135deg, #fa709a 0%, #fee140 100%);
    
    /* Dark Theme Colors */
    --bg-primary: #0f0f23;
    --bg-secondary: #1a1a2e;
    --bg-tertiary: #16213e;
    --bg-card: #1e1e3f;
    
    --text-primary: #ffffff;
    --text-secondary: #b4b4c8;
    --text-muted: #6b6b8c;
    
    --border-color: #2a2a4a;
    --border-hover: #3a3a6a;
    
    --accent-primary: #667eea;
    --accent-secondary: #764ba2;
    
    --success: #00f2fe;
    --warning: #fee140;
    --error: #f5576c;
    
    /* Spacing */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
    
    /* Border Radius */
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    
    /* Shadows */
    --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.5);
    --shadow-glow: 0 0 20px rgba(102, 126, 234, 0.3);
    
    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-base: 250ms ease;
    --transition-slow: 350ms ease;
}

/* Reset & Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* Login Page */
.login-page {
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 100vh;
    background: radial-gradient(ellipse at top, #1a1a2e 0%, #0f0f23 100%);
    position: relative;
    overflow: hidden;
}

.login-page::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle, rgba(102, 126, 234, 0.1) 0%, transparent 70%);
    animation: pulse 15s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% { transform: scale(1); opacity: 0.5; }
    50% { transform: scale(1.1); opacity: 0.8; }
}

.login-container {
    position: relative;
    z-index: 1;
    width: 100%;
    max-width: 420px;
    padding: var(--spacing-lg);
}

.login-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-xl);
    padding: var(--spacing-2xl);
    box-shadow: var(--shadow-lg);
    backdrop-filter: blur(10px);
    animation: slideUp 0.5s ease;
}

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

.login-header {
    text-align: center;
    margin-bottom: var(--spacing-xl);
}

.logo-large {
    margin: 0 auto var(--spacing-lg);
    width: 64px;
    height: 64px;
    animation: float 3s ease-in-out infinite;
}

@keyframes float {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-10px); }
}

.login-header h1 {
    font-size: 1.75rem;
    font-weight: 700;
    background: var(--primary-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: var(--spacing-sm);
}

.login-header p {
    color: var(--text-secondary);
    font-size: 0.875rem;
}

.login-form {
    margin-bottom: var(--spacing-lg);
}

.form-group {
    margin-bottom: var(--spacing-lg);
}

.form-group label {
    display: block;
    margin-bottom: var(--spacing-sm);
    font-weight: 500;
    font-size: 0.875rem;
    color: var(--text-secondary);
}

.form-group input {
    width: 100%;
    padding: 0.75rem 1rem;
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    color: var(--text-primary);
    font-size: 1rem;
    transition: all var(--transition-base);
}

.form-group input:focus {
    outline: none;
    border-color: var(--accent-primary);
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

.btn-primary {
    width: 100%;
    padding: 0.875rem 1.5rem;
    background: var(--primary-gradient);
    border: none;
    border-radius: var(--radius-md);
    color: white;
    font-weight: 600;
    font-size: 1rem;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    transition: all var(--transition-base);
    box-shadow: var(--shadow-md);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg), var(--shadow-glow);
}

.btn-primary:active {
    transform: translateY(0);
}

.error-message {
    padding: 0.75rem 1rem;
    background: rgba(245, 87, 108, 0.1);
    border: 1px solid var(--error);
    border-radius: var(--radius-md);
    color: var(--error);
    font-size: 0.875rem;
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-lg);
    animation: shake 0.5s ease;
}

@keyframes shake {
    0%, 100% { transform: translateX(0); }
    25% { transform: translateX(-10px); }
    75% { transform: translateX(10px); }
}

.login-footer {
    text-align: center;
    padding-top: var(--spacing-lg);
    border-top: 1px solid var(--border-color);
}

.login-footer p {
    color: var(--text-muted);
    font-size: 0.75rem;
}

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

/* Sidebar */
.sidebar {
    width: 260px;
    background: var(--bg-secondary);
    border-right: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    position: fixed;
    height: 100vh;
    z-index: 100;
}

.sidebar-header {
    padding: var(--spacing-xl);
    border-bottom: 1px solid var(--border-color);
}

.logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.logo svg {
    color: var(--accent-primary);
}

.logo h1 {
    font-size: 1.25rem;
    font-weight: 700;
    background: var(--primary-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.sidebar-nav {
    flex: 1;
    padding: var(--spacing-lg);
    overflow-y: auto;
}

.nav-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    padding: 0.75rem 1rem;
    color: var(--text-secondary);
    text-decoration: none;
    border-radius: var(--radius-md);
    transition: all var(--transition-base);
    margin-bottom: var(--spacing-sm);
    font-weight: 500;
    font-size: 0.9375rem;
}

.nav-item:hover {
    background: var(--bg-tertiary);
    color: var(--text-primary);
    transform: translateX(4px);
}

.nav-item.active {
    background: var(--primary-gradient);
    color: white;
    box-shadow: var(--shadow-glow);
}

.sidebar-footer {
    padding: var(--spacing-lg);
    border-top: 1px solid var(--border-color);
}

.nav-item.logout {
    color: var(--error);
}

.nav-item.logout:hover {
    background: rgba(245, 87, 108, 0.1);
}

/* Main Content */
.main-content {
    flex: 1;
    margin-left: 260px;
    padding: var(--spacing-xl);
    background: var(--bg-primary);
}

.view {
    display: none;
    animation: fadeIn 0.3s ease;
}

.view.active {
    display: block;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

/* Cards */
.card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: var(--spacing-xl);
    box-shadow: var(--shadow-sm);
    margin-bottom: var(--spacing-lg);
    transition: all var(--transition-base);
}

.card:hover {
    border-color: var(--border-hover);
    box-shadow: var(--shadow-md);
}

.card-header {
    margin-bottom: var(--spacing-lg);
}

.card-title {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: var(--spacing-sm);
}

.card-subtitle {
    color: var(--text-secondary);
    font-size: 0.875rem;
}

/* Stats Grid */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-xl);
}

.stat-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    position: relative;
    overflow: hidden;
    transition: all var(--transition-base);
}

.stat-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 4px;
    height: 100%;
    background: var(--primary-gradient);
}

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

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

.stat-value {
    font-size: 2rem;
    font-weight: 700;
    background: var(--primary-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

/* Table */
.table-container {
    overflow-x: auto;
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-color);
}

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

thead {
    background: var(--bg-secondary);
}

th {
    padding: 1rem;
    text-align: left;
    font-weight: 600;
    font-size: 0.875rem;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

td {
    padding: 1rem;
    border-top: 1px solid var(--border-color);
}

tbody tr {
    transition: background var(--transition-fast);
}

tbody tr:hover {
    background: var(--bg-tertiary);
}

/* Badges */
.badge {
    display: inline-flex;
    align-items: center;
    padding: 0.25rem 0.75rem;
    border-radius: 9999px;
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.badge-success {
    background: rgba(0, 242, 254, 0.1);
    color: var(--success);
    border: 1px solid var(--success);
}

.badge-warning {
    background: rgba(254, 225, 64, 0.1);
    color: var(--warning);
    border: 1px solid var(--warning);
}

.badge-error {
    background: rgba(245, 87, 108, 0.1);
    color: var(--error);
    border: 1px solid var(--error);
}

.badge-info {
    background: rgba(102, 126, 234, 0.1);
    color: var(--accent-primary);
    border: 1px solid var(--accent-primary);
}

/* Buttons */
.btn {
    padding: 0.625rem 1.25rem;
    border-radius: var(--radius-md);
    font-weight: 600;
    font-size: 0.875rem;
    cursor: pointer;
    transition: all var(--transition-base);
    border: none;
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.btn-secondary {
    background: var(--bg-tertiary);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
}

.btn-secondary:hover {
    background: var(--bg-secondary);
    border-color: var(--border-hover);
}

.btn-success {
    background: var(--success-gradient);
    color: white;
    box-shadow: var(--shadow-sm);
}

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

/* Progress Bar */
.progress-bar {
    height: 8px;
    background: var(--bg-secondary);
    border-radius: 9999px;
    overflow: hidden;
    position: relative;
}

.progress-fill {
    height: 100%;
    background: var(--primary-gradient);
    border-radius: 9999px;
    transition: width var(--transition-slow);
    position: relative;
    overflow: hidden;
}

.progress-fill::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.3), transparent);
    animation: shimmer 2s infinite;
}

@keyframes shimmer {
    0% { transform: translateX(-100%); }
    100% { transform: translateX(100%); }
}

/* Responsive */
@media (max-width: 768px) {
    .sidebar {
        transform: translateX(-100%);
    }
    
    .main-content {
        margin-left: 0;
    }
    
    .stats-grid {
        grid-template-columns: 1fr;
    }
}