/* Design System & Variables */
:root {
    --primary-color: #2563EB; /* Royal Blue */
    --primary-dark: #1E40AF;
    --accent-color: #06B6D4; /* Cyan */
    --text-main: #1E293B; /* Slate 800 */
    --text-secondary: #64748B; /* Slate 500 */
    --bg-body: #F1F5F9; /* Slate 100 */
    --bg-surface: #FFFFFF;
    --border-color: #E2E8F0;
    --success-color: #10B981;
    --warning-color: #F59E0B;
    --danger-color: #EF4444;
    
    --font-heading: 'Outfit', 'Inter', sans-serif;
    --font-body: 'Inter', sans-serif;
    
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
    
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
}

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

body {
    font-family: var(--font-body);
    background-color: var(--bg-body);
    color: var(--text-main);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-heading);
    color: #0F172A; /* Slate 900 */
    margin-bottom: 0.75rem;
    font-weight: 600;
}

/* Layout */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 2rem;
}

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

header h1 {
    font-size: 2.5rem;
    background: linear-gradient(135deg, var(--primary-color), var(--accent-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    margin-bottom: 0.5rem;
}

header p {
    color: var(--text-secondary);
    font-size: 1.1rem;
}

/* Tabs Navigation */
.tabs-nav {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin-bottom: 2rem;
    background: var(--bg-surface);
    padding: 0.5rem;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
    width: fit-content;
    margin-left: auto;
    margin-right: auto;
}

.tab-btn {
    padding: 0.75rem 1.5rem;
    border: none;
    background: transparent;
    font-family: var(--font-heading);
    font-weight: 500;
    color: var(--text-secondary);
    cursor: pointer;
    border-radius: var(--radius-md);
    transition: all 0.3s ease;
}

.tab-btn:hover {
    color: var(--primary-color);
    background-color: #EFF6FF;
}

.tab-btn.active {
    background-color: var(--primary-color);
    color: white;
    box-shadow: var(--shadow-sm);
}

/* Tab Content */
.tab-content {
    display: none;
    animation: fadeIn 0.4s ease;
}

.tab-content.active {
    display: block;
}

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

/* Dashboard Cards */
.card {
    background: var(--bg-surface);
    border-radius: var(--radius-lg);
    padding: 1.5rem;
    margin-bottom: 1.5rem;
    box-shadow: var(--shadow-md);
    border: 1px solid var(--border-color);
}

.card-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1.25rem;
    padding-bottom: 1rem;
    border-bottom: 1px solid var(--border-color);
}

.card-title {
    font-size: 1.25rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.card-title::before {
    content: '';
    display: block;
    width: 6px;
    height: 24px;
    background: var(--primary-color);
    border-radius: 4px;
}

/* Data Tables */
.table-container {
    overflow-x: auto;
}

table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.95rem;
}

th, td {
    padding: 1rem;
    text-align: left;
    border-bottom: 1px solid var(--border-color);
}

th {
    background-color: #F8FAFC;
    color: var(--text-secondary);
    font-weight: 600;
    text-transform: uppercase;
    font-size: 0.85rem;
    letter-spacing: 0.05em;
}

tr:hover td {
    background-color: #F8FAFC;
}

/* Badge/Tags */
.badge {
    display: inline-block;
    padding: 0.25rem 0.75rem;
    border-radius: 9999px;
    font-size: 0.75rem;
    font-weight: 600;
}

.badge-primary { background: #DBEAFE; color: #1E40AF; }
.badge-success { background: #D1FAE5; color: #065F46; }
.badge-warning { background: #FEF3C7; color: #92400E; }
.badge-danger { background: #FEE2E2; color: #991B1B; }

/* Grid Layouts */
.grid-2 {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
    gap: 1.5rem;
}

/* Footer */
footer {
    text-align: center;
    margin-top: 3rem;
    color: var(--text-secondary);
    font-size: 0.9rem;
    padding-bottom: 2rem;
}

/* Responsive */
@media (max-width: 768px) {
    .tabs-nav { flex-direction: column; width: 100%; }
    .grid-2 { grid-template-columns: 1fr; }
}