:root {
    --primary: #667eea;
    --primary-dark: #5a67d8;
    --secondary: #764ba2;
    --success: #48bb78;
    --warning: #ed8936;
    --danger: #f56565;
    --dark: #1a202c;
    --gray-100: #f7fafc;
    --gray-200: #edf2f7;
    --gray-300: #e2e8f0;
    --gray-400: #cbd5e0;
    --gray-500: #a0aec0;
    --gray-600: #718096;
    --gray-700: #4a5568;
    --gray-800: #2d3748;
    --sidebar-width: 260px;
}

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: var(--gray-100);
    color: var(--gray-800);
    line-height: 1.6;
}

/* ========== LAYOUT ========== */
.admin-wrapper {
    display: flex;
    min-height: 100vh;
}

/* Sidebar */
.sidebar {
    width: var(--sidebar-width);
    background: linear-gradient(180deg, var(--dark) 0%, #2d3748 100%);
    color: white;
    position: fixed;
    height: 100vh;
    overflow-y: auto;
    z-index: 100;
}

.sidebar-header {
    padding: 25px 20px;
    border-bottom: 1px solid rgba(255,255,255,0.1);
}

.sidebar-header h1 {
    font-size: 20px;
    font-weight: 700;
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.sidebar-header span {
    font-size: 11px;
    color: var(--gray-500);
    text-transform: uppercase;
    letter-spacing: 1px;
}

.sidebar-nav {
    padding: 20px 0;
}

.nav-section {
    margin-bottom: 25px;
}

.nav-section-title {
    font-size: 11px;
    text-transform: uppercase;
    letter-spacing: 1px;
    color: var(--gray-500);
    padding: 0 20px 10px;
}

.nav-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px 20px;
    color: var(--gray-400);
    text-decoration: none;
    transition: all 0.2s;
    border-left: 3px solid transparent;
}

.nav-item:hover {
    background: rgba(255,255,255,0.05);
    color: white;
}

.nav-item.active {
    background: rgba(102, 126, 234, 0.15);
    color: var(--primary);
    border-left-color: var(--primary);
}

.nav-item svg { width: 20px; height: 20px; }

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

.topbar {
    background: white;
    padding: 15px 30px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-bottom: 1px solid var(--gray-200);
    position: sticky;
    top: 0;
    z-index: 50;
}

.topbar-title h2 {
    font-size: 20px;
    font-weight: 600;
}

.topbar-title p {
    font-size: 13px;
    color: var(--gray-500);
}

.topbar-actions {
    display: flex;
    align-items: center;
    gap: 15px;
}

.user-menu {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 8px 15px;
    background: var(--gray-100);
    border-radius: 8px;
    cursor: pointer;
}

.user-menu img {
    width: 32px;
    height: 32px;
    border-radius: 50%;
}

.content {
    padding: 30px;
}

/* ========== CARDS ========== */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 20px;
    margin-bottom: 30px;
}

.stat-card {
    background: white;
    border-radius: 12px;
    padding: 25px;
    box-shadow: 0 1px 3px rgba(0,0,0,0.1);
}

.stat-card.gradient-1 { background: linear-gradient(135deg, #667eea 0%, #764ba2 100%); color: white; }
.stat-card.gradient-2 { background: linear-gradient(135deg, #f093fb 0%, #f5576c 100%); color: white; }
.stat-card.gradient-3 { background: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%); color: white; }
.stat-card.gradient-4 { background: linear-gradient(135deg, #43e97b 0%, #38f9d7 100%); color: white; }

.stat-card h3 {
    font-size: 13px;
    font-weight: 500;
    opacity: 0.9;
    margin-bottom: 10px;
}

.stat-card .value {
    font-size: 32px;
    font-weight: 700;
}

.stat-card .change {
    font-size: 12px;
    margin-top: 10px;
    opacity: 0.8;
}

/* ========== TABLES ========== */
.card {
    background: white;
    border-radius: 12px;
    box-shadow: 0 1px 3px rgba(0,0,0,0.1);
    margin-bottom: 20px;
}

.card-header {
    padding: 20px 25px;
    border-bottom: 1px solid var(--gray-200);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.card-header h3 {
    font-size: 16px;
    font-weight: 600;
}

.card-body { padding: 25px; }

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

th, td {
    padding: 12px 15px;
    text-align: left;
    border-bottom: 1px solid var(--gray-200);
}

th {
    font-size: 12px;
    font-weight: 600;
    text-transform: uppercase;
    color: var(--gray-500);
    background: var(--gray-50);
}

tr:hover { background: var(--gray-50); }

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

.form-group label {
    display: block;
    font-size: 14px;
    font-weight: 500;
    margin-bottom: 8px;
    color: var(--gray-700);
}

.form-group input,
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 12px 15px;
    border: 2px solid var(--gray-200);
    border-radius: 8px;
    font-size: 14px;
    transition: border-color 0.2s;
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary);
}

.form-group .help {
    font-size: 12px;
    color: var(--gray-500);
    margin-top: 5px;
}

.form-row {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 20px;
}

/* ========== BUTTONS ========== */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 10px 20px;
    border: none;
    border-radius: 8px;
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s;
    text-decoration: none;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    color: white;
}
.btn-primary:hover { opacity: 0.9; transform: translateY(-1px); }

.btn-success { background: var(--success); color: white; }
.btn-danger { background: var(--danger); color: white; }
.btn-outline {
    background: transparent;
    border: 2px solid var(--gray-300);
    color: var(--gray-700);
}
.btn-outline:hover { border-color: var(--primary); color: var(--primary); }

.btn-sm { padding: 6px 12px; font-size: 12px; }
.btn-lg { padding: 15px 30px; font-size: 16px; }

/* ========== BADGES ========== */
.badge {
    display: inline-block;
    padding: 4px 10px;
    border-radius: 20px;
    font-size: 11px;
    font-weight: 600;
    text-transform: uppercase;
}

.badge-success { background: #c6f6d5; color: #22543d; }
.badge-warning { background: #feebc8; color: #744210; }
.badge-danger { background: #fed7d7; color: #822727; }
.badge-info { background: #bee3f8; color: #2a4365; }

/* ========== ALERTS ========== */
.alert {
    padding: 15px 20px;
    border-radius: 8px;
    margin-bottom: 20px;
    display: flex;
    align-items: center;
    gap: 10px;
}

.alert-success { background: #c6f6d5; color: #22543d; }
.alert-danger { background: #fed7d7; color: #822727; }
.alert-warning { background: #feebc8; color: #744210; }
.alert-info { background: #bee3f8; color: #2a4365; }

/* ========== LOGIN ========== */
.login-container {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
}

.login-box {
    background: white;
    padding: 40px;
    border-radius: 16px;
    box-shadow: 0 20px 60px rgba(0,0,0,0.3);
    width: 100%;
    max-width: 400px;
}

.login-box h1 {
    text-align: center;
    margin-bottom: 30px;
    font-size: 24px;
}

.login-box .btn { width: 100%; justify-content: center; }

/* ========== UTILITIES ========== */
.text-center { text-align: center; }
.text-right { text-align: right; }
.text-muted { color: var(--gray-500); }
.text-success { color: var(--success); }
.text-danger { color: var(--danger); }
.mb-0 { margin-bottom: 0; }
.mb-2 { margin-bottom: 10px; }
.mb-4 { margin-bottom: 20px; }
.mt-4 { margin-top: 20px; }

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