/* ===== Design Tokens & Variables ===== */
:root {
    --bg-primary: #0a0a0f;
    --bg-secondary: #12121a;
    --bg-card: rgba(255, 255, 255, 0.03);
    --bg-card-hover: rgba(255, 255, 255, 0.06);
    --bg-input: rgba(0, 0, 0, 0.2);
    
    --border-color: rgba(255, 255, 255, 0.08);
    --border-color-hover: rgba(255, 255, 255, 0.15);
    
    --text-primary: #e2e8f0;
    --text-secondary: #94a3b8;
    --text-muted: #64748b;
    
    --accent-primary: #6366f1;
    --accent-secondary: #8b5cf6;
    --accent-gradient: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
    
    --success: #10b981;
    --warning: #f59e0b;
    --danger: #ef4444;
    --info: #3b82f6;
    
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-xl: 24px;
    
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.5);
    --shadow-glow: 0 0 15px rgba(99, 102, 241, 0.3);
    
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --sidebar-width: 260px;
    --sidebar-collapsed-width: 70px;
}

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.5;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
}

a {
    color: var(--accent-primary);
    text-decoration: none;
    transition: var(--transition);
}

a:hover {
    color: var(--accent-secondary);
}

h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.2;
    margin-bottom: 1rem;
}

.hidden {
    display: none !important;
}

/* Scrollbar */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}
::-webkit-scrollbar-track {
    background: var(--bg-primary);
}
::-webkit-scrollbar-thumb {
    background: var(--bg-secondary);
    border-radius: var(--radius-sm);
}
::-webkit-scrollbar-thumb:hover {
    background: var(--text-muted);
}

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

/* ===== Sidebar ===== */
.sidebar {
    width: var(--sidebar-width);
    background-color: var(--bg-secondary);
    border-right: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    position: fixed;
    top: 0;
    left: 0;
    height: 100vh;
    transition: width var(--transition);
    z-index: 100;
}

.sidebar.collapsed {
    width: var(--sidebar-collapsed-width);
}

.sidebar-header {
    height: 70px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 20px;
    border-bottom: 1px solid var(--border-color);
}

.brand-text {
    font-size: 1.2rem;
    font-weight: 700;
    background: var(--accent-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    margin: 0;
    white-space: nowrap;
    transition: opacity var(--transition);
}

.sidebar.collapsed .brand-text {
    opacity: 0;
    width: 0;
    display: none;
}

.icon-btn {
    background: transparent;
    border: none;
    color: var(--text-secondary);
    font-size: 1.5rem;
    cursor: pointer;
    transition: var(--transition);
    display: flex;
    align-items: center;
    justify-content: center;
    width: 32px;
    height: 32px;
    border-radius: var(--radius-sm);
}

.icon-btn:hover {
    color: var(--text-primary);
    background-color: var(--bg-card);
}

.sidebar-nav {
    flex: 1;
    padding: 20px 0;
    overflow-y: auto;
}

.nav-link {
    display: flex;
    align-items: center;
    padding: 12px 20px;
    color: var(--text-secondary);
    transition: var(--transition);
    border-left: 3px solid transparent;
    margin-bottom: 4px;
}

.nav-link:hover {
    background-color: var(--bg-card);
    color: var(--text-primary);
}

.nav-link.active {
    background-color: var(--bg-card-hover);
    color: var(--text-primary);
    border-left-color: var(--accent-primary);
}

.nav-icon {
    font-size: 1.2rem;
    min-width: 30px;
}

.nav-text {
    margin-left: 10px;
    white-space: nowrap;
    transition: opacity var(--transition);
}

.sidebar.collapsed .nav-text {
    opacity: 0;
    width: 0;
    display: none;
}

.sidebar-footer {
    padding: 20px;
    border-top: 1px solid var(--border-color);
}

.user-info {
    display: flex;
    align-items: center;
}

.user-avatar {
    width: 36px;
    height: 36px;
    background: var(--accent-gradient);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.2rem;
    min-width: 36px;
}

.user-details {
    margin-left: 12px;
    display: flex;
    flex-direction: column;
    white-space: nowrap;
    transition: opacity var(--transition);
}

.sidebar.collapsed .user-details {
    opacity: 0;
    width: 0;
    display: none;
}

.username {
    font-weight: 500;
    font-size: 0.9rem;
}

.logout-link {
    font-size: 0.8rem;
    color: var(--text-muted);
}
.logout-link:hover {
    color: var(--danger);
}

/* ===== Main Content ===== */
.main-content {
    flex: 1;
    margin-left: var(--sidebar-width);
    padding: 32px 40px;
    transition: margin-left var(--transition);
    min-height: 100vh;
}

.sidebar.collapsed ~ .main-content {
    margin-left: var(--sidebar-collapsed-width);
}

.page-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 32px;
    position: relative;
    padding-bottom: 16px;
}

.page-header::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 60px;
    height: 4px;
    background: var(--accent-gradient);
    border-radius: 2px;
}

.page-title h2 {
    font-size: 1.8rem;
    margin-bottom: 4px;
}

.page-subtitle {
    color: var(--text-secondary);
    font-size: 0.95rem;
}

.page-actions {
    display: flex;
    gap: 12px;
}

/* ===== Components ===== */

/* Glass Cards */
.glass-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 24px;
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    transition: var(--transition);
    box-shadow: var(--shadow-sm);
}

.glass-card:hover {
    background: var(--bg-card-hover);
    border-color: var(--border-color-hover);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

/* Grid Layouts */
.grid-4 {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
    margin-bottom: 32px;
}

.grid-2 {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
    margin-bottom: 32px;
}

/* KPI Cards */
.kpi-card {
    display: flex;
    align-items: center;
}

.kpi-icon {
    width: 50px;
    height: 50px;
    border-radius: var(--radius-md);
    background: rgba(99, 102, 241, 0.1);
    color: var(--accent-primary);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    margin-right: 16px;
}

.kpi-content {
    flex: 1;
}

.kpi-label {
    color: var(--text-secondary);
    font-size: 0.85rem;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-bottom: 4px;
}

.kpi-value {
    font-size: 1.8rem;
    font-weight: 700;
    line-height: 1;
}

.kpi-trend {
    display: flex;
    align-items: center;
    font-size: 0.8rem;
    margin-top: 6px;
}

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

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 10px 20px;
    font-size: 0.95rem;
    font-weight: 500;
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: var(--transition);
    border: none;
    outline: none;
    font-family: 'Inter', sans-serif;
    gap: 8px;
}

.btn-primary {
    background: var(--accent-gradient);
    color: white;
    box-shadow: 0 4px 15px rgba(99, 102, 241, 0.4);
}

.btn-primary:hover {
    transform: translateY(-1px);
    box-shadow: 0 6px 20px rgba(99, 102, 241, 0.6);
    color: white;
}

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

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

.btn-danger {
    background: rgba(239, 68, 68, 0.1);
    color: var(--danger);
    border: 1px solid rgba(239, 68, 68, 0.2);
}

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

.btn-icon {
    padding: 8px;
    background: transparent;
    border: 1px solid transparent;
    color: var(--text-secondary);
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: var(--transition);
    display: inline-flex;
    align-items: center;
    justify-content: center;
}

.btn-icon:hover {
    background: var(--bg-card);
    color: var(--text-primary);
    border-color: var(--border-color);
}

.btn-sm {
    padding: 6px 12px;
    font-size: 0.85rem;
}

.btn-block {
    width: 100%;
}

/* Forms */
.form-group {
    margin-bottom: 20px;
}

label {
    display: block;
    margin-bottom: 8px;
    color: var(--text-secondary);
    font-size: 0.9rem;
    font-weight: 500;
}

input[type="text"],
input[type="password"],
input[type="number"],
input[type="email"],
select,
textarea {
    width: 100%;
    padding: 12px 16px;
    background-color: var(--bg-input);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    color: var(--text-primary);
    font-family: 'Inter', sans-serif;
    font-size: 0.95rem;
    transition: var(--transition);
}

input:focus,
select:focus,
textarea:focus {
    outline: none;
    border-color: var(--accent-primary);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.2);
}

/* Custom Range Slider */
input[type="range"] {
    -webkit-appearance: none;
    width: 100%;
    height: 6px;
    background: var(--bg-input);
    border-radius: 3px;
    outline: none;
}

input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background: var(--accent-primary);
    cursor: pointer;
    box-shadow: 0 0 10px rgba(99, 102, 241, 0.5);
    transition: var(--transition);
}

input[type="range"]::-webkit-slider-thumb:hover {
    transform: scale(1.2);
}

/* Tables */
.table-container {
    width: 100%;
    overflow-x: auto;
    border-radius: var(--radius-md);
    border: 1px solid var(--border-color);
    background: var(--bg-card);
}

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

th {
    padding: 16px 20px;
    background-color: var(--bg-secondary);
    color: var(--text-secondary);
    font-size: 0.8rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    border-bottom: 1px solid var(--border-color);
}

td {
    padding: 16px 20px;
    border-bottom: 1px solid var(--border-color);
    font-size: 0.95rem;
    color: var(--text-primary);
    vertical-align: middle;
}

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

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

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

/* Badges */
.badge {
    display: inline-block;
    padding: 4px 10px;
    border-radius: 20px;
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.badge-success { background: rgba(16, 185, 129, 0.1); color: var(--success); border: 1px solid rgba(16, 185, 129, 0.2); }
.badge-danger { background: rgba(239, 68, 68, 0.1); color: var(--danger); border: 1px solid rgba(239, 68, 68, 0.2); }
.badge-warning { background: rgba(245, 158, 11, 0.1); color: var(--warning); border: 1px solid rgba(245, 158, 11, 0.2); }
.badge-info { background: rgba(59, 130, 246, 0.1); color: var(--info); border: 1px solid rgba(59, 130, 246, 0.2); }
.badge-default { background: rgba(100, 116, 139, 0.1); color: var(--text-secondary); border: 1px solid rgba(100, 116, 139, 0.2); }

.badge-pulse {
    position: relative;
}
.badge-pulse::before {
    content: '';
    position: absolute;
    left: -4px;
    top: 50%;
    transform: translateY(-50%);
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background-color: currentColor;
    animation: pulse 2s infinite;
}

/* Modals */
.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background: rgba(0, 0, 0, 0.6);
    backdrop-filter: blur(5px);
    z-index: 1000;
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    visibility: hidden;
    transition: var(--transition);
}

.modal-overlay.active {
    opacity: 1;
    visibility: visible;
}

.modal-content {
    background: var(--bg-secondary);
    width: 90%;
    max-width: 500px;
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-color);
    box-shadow: var(--shadow-lg);
    transform: translateY(20px);
    transition: transform 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
    max-height: 90vh;
    display: flex;
    flex-direction: column;
}

.modal-overlay.active .modal-content {
    transform: translateY(0);
}

.modal-header {
    padding: 20px 24px;
    border-bottom: 1px solid var(--border-color);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.modal-header h3 {
    margin: 0;
    font-size: 1.25rem;
}

.modal-close {
    background: transparent;
    border: none;
    color: var(--text-secondary);
    font-size: 1.5rem;
    cursor: pointer;
    transition: var(--transition);
}

.modal-close:hover {
    color: var(--text-primary);
}

.modal-body {
    padding: 24px;
    overflow-y: auto;
}

.modal-footer {
    padding: 20px 24px;
    border-top: 1px solid var(--border-color);
    display: flex;
    justify-content: flex-end;
    gap: 12px;
}

/* Toast Notifications */
.toast-container {
    position: fixed;
    top: 24px;
    right: 24px;
    z-index: 9999;
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.toast {
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    padding: 16px 20px;
    color: var(--text-primary);
    box-shadow: var(--shadow-md);
    min-width: 300px;
    display: flex;
    align-items: flex-start;
    animation: slideInRight 0.3s forwards;
    position: relative;
    overflow: hidden;
}

.toast.toast-success { border-left: 4px solid var(--success); }
.toast.toast-error { border-left: 4px solid var(--danger); }
.toast.toast-warning { border-left: 4px solid var(--warning); }
.toast.toast-info { border-left: 4px solid var(--info); }

.toast-message {
    flex: 1;
    font-size: 0.9rem;
}

.toast-progress {
    position: absolute;
    bottom: 0;
    left: 0;
    height: 3px;
    background: rgba(255, 255, 255, 0.2);
    width: 100%;
}

.toast.toast-success .toast-progress { background: var(--success); }
.toast.toast-error .toast-progress { background: var(--danger); }

/* Login Page */
.login-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background: linear-gradient(-45deg, #0a0a0f, #12121a, #1a1a2e, #0f172a);
    background-size: 400% 400%;
    animation: gradientBG 15s ease infinite;
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 9999;
}

.login-card {
    width: 100%;
    max-width: 400px;
    padding: 40px;
}

.login-header {
    text-align: center;
    margin-bottom: 32px;
}

.login-header h2 {
    font-size: 2rem;
    margin-bottom: 8px;
    background: var(--accent-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.error-message {
    color: var(--danger);
    font-size: 0.85rem;
    background: rgba(239, 68, 68, 0.1);
    border: 1px solid rgba(239, 68, 68, 0.2);
    padding: 10px;
    border-radius: var(--radius-sm);
    margin-bottom: 16px;
    text-align: center;
}

/* Utility Classes & Animations */
.text-center { text-align: center; }
.text-right { text-align: right; }
.mt-4 { margin-top: 16px; }
.mb-4 { margin-bottom: 16px; }
.flex { display: flex; }
.items-center { align-items: center; }
.justify-between { justify-content: space-between; }
.gap-2 { gap: 8px; }

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

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

@keyframes slideInRight {
    from { opacity: 0; transform: translateX(50px); }
    to { opacity: 1; transform: translateX(0); }
}

@keyframes pulse {
    0% { transform: translateY(-50%) scale(0.95); box-shadow: 0 0 0 0 rgba(59, 130, 246, 0.7); }
    70% { transform: translateY(-50%) scale(1); box-shadow: 0 0 0 6px rgba(59, 130, 246, 0); }
    100% { transform: translateY(-50%) scale(0.95); box-shadow: 0 0 0 0 rgba(59, 130, 246, 0); }
}

@keyframes gradientBG {
    0% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
    100% { background-position: 0% 50%; }
}

.animate-fade-in { animation: fadeIn 0.5s ease forwards; }
.animate-slide-up { animation: slideUp 0.5s cubic-bezier(0.175, 0.885, 0.32, 1.275) forwards; }

.delay-100 { animation-delay: 0.1s; }
.delay-200 { animation-delay: 0.2s; }
.delay-300 { animation-delay: 0.3s; }

/* Shimmer Loading */
.skeleton {
    background: linear-gradient(90deg, var(--bg-card) 25%, var(--bg-card-hover) 50%, var(--bg-card) 75%);
    background-size: 200% 100%;
    animation: shimmer 1.5s infinite;
    border-radius: var(--radius-sm);
}

@keyframes shimmer {
    0% { background-position: 200% 0; }
    100% { background-position: -200% 0; }
}

/* Charts container */
.chart-container {
    height: 300px;
    width: 100%;
    position: relative;
    margin-top: 16px;
}

/* Progress bar (Device split) */
.progress-bar-container {
    height: 12px;
    background: var(--bg-input);
    border-radius: 6px;
    overflow: hidden;
    display: flex;
}

.progress-bar-fill {
    height: 100%;
    background: var(--accent-gradient);
    transition: width 1s ease-in-out;
}

/* Media Queries */
@media (max-width: 1200px) {
    .grid-4 { grid-template-columns: repeat(3, 1fr); }
}

@media (max-width: 992px) {
    .sidebar { width: var(--sidebar-collapsed-width); }
    .sidebar .brand-text, .sidebar .nav-text, .sidebar .user-details { display: none; }
    .main-content { margin-left: var(--sidebar-collapsed-width); }
    .grid-4 { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 768px) {
    .grid-2 { grid-template-columns: 1fr; }
    .main-content { padding: 20px; }
}

@media (max-width: 576px) {
    .grid-4 { grid-template-columns: 1fr; }
    .page-header { flex-direction: column; gap: 16px; }
}