:root {
    /* Color Palette - Premium Dark Theme */
    --bg-dark: #0f172a;
    --bg-card: rgba(30, 41, 59, 0.7);
    --bg-sidebar: #1e293b;
    --accent: #38bdf8;
    --accent-glow: rgba(56, 189, 248, 0.3);
    --text-primary: #f8fafc;
    --text-secondary: #94a3b8;
    --border-color: rgba(255, 255, 255, 0.1);
    --sidebar-width: 260px;
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --glass-blur: blur(12px);
}

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

body {
    background-color: var(--bg-dark);
    color: var(--text-primary);
    overflow: hidden;
    height: 100vh;
}

.app-container {
    display: flex;
    height: 100vh;
    width: 100vw;
}

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

.sidebar-header {
    padding: 2rem 1.5rem;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--accent);
}

.logo-icon {
    width: 28px;
    height: 28px;
    filter: drop-shadow(0 0 8px var(--accent-glow));
}

.sidebar-nav {
    flex: 1;
    padding: 1rem 0.75rem;
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.nav-item {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 0.875rem 1rem;
    text-decoration: none;
    color: var(--text-secondary);
    border-radius: 12px;
    transition: var(--transition);
    font-weight: 500;
}

.nav-item:hover {
    background: rgba(255, 255, 255, 0.05);
    color: var(--text-primary);
    transform: translateX(4px);
}

.nav-item.active {
    background: var(--accent);
    color: white;
    box-shadow: 0 4px 15px var(--accent-glow);
}

.sidebar-footer {
    padding: 1.5rem;
    border-top: 1px solid var(--border-color);
}

.user-profile {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.avatar {
    width: 40px;
    height: 40px;
    background: linear-gradient(135deg, var(--accent), #818cf8);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 0.875rem;
}

.user-info {
    display: flex;
    flex-direction: column;
}

.user-name {
    font-size: 0.875rem;
    font-weight: 600;
}

.user-role {
    font-size: 0.75rem;
    color: var(--text-secondary);
}

/* Main Content Styling */
.main-content {
    flex: 1;
    overflow-y: auto;
    display: flex;
    flex-direction: column;
    position: relative;
    background: radial-gradient(circle at top right, rgba(56, 189, 248, 0.05), transparent);
}

.top-header {
    height: 80px;
    padding: 0 2.5rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
    border-bottom: 1px solid var(--border-color);
    background: rgba(15, 23, 42, 0.8);
    backdrop-filter: var(--glass-blur);
    position: sticky;
    top: 0;
    z-index: 90;
}

.top-header h1 {
    font-size: 1.5rem;
    font-weight: 700;
    letter-spacing: -0.02em;
}

.header-actions {
    display: flex;
    align-items: center;
    gap: 1.5rem;
}

.icon-btn {
    background: transparent;
    border: 1px solid var(--border-color);
    color: var(--text-secondary);
    width: 40px;
    height: 40px;
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: var(--transition);
}

.icon-btn:hover {
    border-color: var(--accent);
    color: var(--accent);
}

.date-display {
    padding: 0.5rem 1rem;
    background: rgba(255, 255, 255, 0.05);
    border-radius: 10px;
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--text-secondary);
}

.content-area {
    padding: 2.5rem;
    flex: 1;
}

/* Loader Styling */
.loader-container {
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
}

.spinner {
    width: 40px;
    height: 40px;
    border: 3px solid rgba(56, 189, 248, 0.1);
    border-radius: 50%;
    border-top-color: var(--accent);
    animation: spin 1s linear infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

/* Responsive Grid/Cards (to be used later) */
.glass-card {
    background: var(--bg-card);
    backdrop-filter: var(--glass-blur);
    border: 1px solid var(--border-color);
    border-radius: 20px;
    padding: 1.5rem;
    transition: var(--transition);
}

.glass-card:hover {
    border-color: rgba(56, 189, 248, 0.3);
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.2);
}

/* Dashboard Layout */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1.5rem;
    margin-bottom: 2rem;
}

@media (max-width: 768px) {
    .stats-grid {
        grid-template-columns: 1fr;
    }
}

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

.stat-card {
    display: flex;
    flex-direction: column;
    justify-content: center;
    gap: 0.75rem;
    min-height: 120px;
}

.stat-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 0.25rem;
}

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

.stat-icon {
    width: 36px;
    height: 36px;
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.stat-icon i {
    width: 20px;
    height: 20px;
}

.stat-value {
    font-size: 2rem;
    font-weight: 700;
    color: var(--text-primary);
    letter-spacing: -0.02em;
}

.chart-card {
    grid-column: span 2;
    min-height: 400px;
}

.chart-card.full-width {
    grid-column: 1 / -1;
}

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

@media (max-width: 1024px) {
    .chart-card {
        grid-column: 1 / -1;
    }
}

/* Modal System */
.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(15, 23, 42, 0.9);
    backdrop-filter: blur(8px);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 9999;
    opacity: 0;
    pointer-events: none;
    transition: var(--transition);
}

.modal-overlay.active {
    opacity: 1;
    pointer-events: all;
}

.modal-content {
    background: var(--bg-sidebar);
    width: 90%;
    max-width: 550px;
    border: 1px solid var(--border-color);
    border-radius: 24px;
    padding: 2.5rem;
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.5);
    transform: scale(0.9);
    transition: var(--transition);
}

.modal-overlay.active .modal-content {
    transform: scale(1);
}

/* Forms & Inputs */
.form-group {
    margin-bottom: 1.5rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--text-secondary);
}

.form-control {
    width: 100%;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 0.875rem 1.25rem;
    color: var(--text-primary);
    outline: none;
    transition: var(--transition);
}

.form-control:focus {
    border-color: var(--accent);
    box-shadow: 0 0 0 4px var(--accent-glow);
}

select.form-control {
    appearance: none;
    -webkit-appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='24' height='24' viewBox='0 0 24 24' fill='none' stroke='%2394a3b8' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='m6 9 6 6 6-6'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 1rem center;
    background-size: 1.2rem;
    padding-right: 3rem;
}

select.form-control option {
    background-color: var(--bg-sidebar);
    color: var(--text-primary);
    padding: 10px;
}

/* Utility Components */
.btn-primary {
    background: var(--accent);
    color: white;
    border: none;
    padding: 0.75rem 1.5rem;
    border-radius: 12px;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 25px var(--accent-glow);
}

.badge {
    padding: 0.35rem 0.75rem;
    border-radius: 100px;
    font-size: 0.75rem;
    font-weight: 700;
    text-transform: uppercase;
}

.badge-success { background: rgba(34, 197, 94, 0.1); color: #4ade80; border: 1px solid rgba(34, 197, 94, 0.2); }
.badge-error { background: rgba(239, 68, 68, 0.1); color: #f87171; border: 1px solid rgba(239, 68, 68, 0.2); }

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

th {
    text-align: left;
    padding: 1rem;
    color: var(--text-secondary);
    font-weight: 600;
    font-size: 0.875rem;
    border-bottom: 1px solid var(--border-color);
}

td {
    padding: 1.25rem 1rem;
    border-bottom: 1px solid var(--border-color);
}

/* Login Overlay & Card */
.login-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background: radial-gradient(circle at center, #1e293b 0%, #0f172a 100%);
    display: none;
    align-items: center;
    justify-content: center;
    z-index: 10000;
}

.login-overlay.active {
    display: flex;
}

.login-card {
    width: 100%;
    max-width: 420px;
    padding: 3rem;
    animation: fadeInScale 0.5s cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: 0 40px 100px rgba(0, 0, 0, 0.6);
}

@keyframes fadeInScale {
    from { opacity: 0; transform: scale(0.95) translateY(20px); }
    to { opacity: 1; transform: scale(1) translateY(0); }
}

.login-header {
    text-align: center;
    margin-bottom: 2.5rem;
}

.login-header .logo {
    justify-content: center;
    font-size: 2rem;
    margin-bottom: 1rem;
}

.login-header p {
    color: var(--text-secondary);
    font-size: 0.875rem;
    margin-top: -0.5rem;
}

.status-indicator {
    display: inline-block;
    padding: 4px 10px;
    background: rgba(56, 189, 248, 0.1);
    color: var(--accent);
    border-radius: 20px;
    font-size: 0.65rem;
    font-weight: 700;
    text-transform: uppercase;
    margin-top: 1rem;
    letter-spacing: 0.05em;
    border: 1px solid var(--accent-glow);
}

.login-footer {
    text-align: center;
    margin-top: 2.5rem;
    color: var(--text-secondary);
    font-size: 0.75rem;
    opacity: 0.6;
}

#login-form .btn-primary:active {
    transform: scale(0.98);
}