:root {
    --primary: #6366F1;
    --primary-hover: #4F46E5;
    --secondary: #10B981;
    --secondary-hover: #059669;
    --danger: #EF4444;
    --danger-hover: #DC2626;
    --background: #F8FAFC;
    --surface: #FFFFFF;
    --text-main: #0F172A;
    --text-muted: #64748B;
    --border: #E2E8F0;
}

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

body {
    background-color: var(--background);
    color: var(--text-main);
    min-height: 100vh;
    display: flex;
}

/* Sidebar */
.sidebar {
    width: 280px;
    background: linear-gradient(180deg, #1E293B 0%, #0F172A 100%);
    color: white;
    display: flex;
    flex-direction: column;
    box-shadow: 4px 0 15px rgba(0,0,0,0.05);
}

.sidebar-header {
    padding: 2rem 1.5rem;
    font-size: 1.5rem;
    font-weight: 800;
    letter-spacing: -0.025em;
    background: rgba(255, 255, 255, 0.05);
    border-bottom: 1px solid rgba(255,255,255,0.1);
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.sidebar-menu {
    flex: 1;
    padding: 1.5rem 1rem;
}

.menu-item {
    display: flex;
    align-items: center;
    padding: 1rem 1.5rem;
    color: #CBD5E1;
    text-decoration: none;
    border-radius: 0.75rem;
    margin-bottom: 0.5rem;
    font-weight: 500;
    transition: all 0.3s ease;
}

.menu-item:hover, .menu-item.active {
    background: rgba(99, 102, 241, 0.15);
    color: white;
    transform: translateX(4px);
}

.sidebar-footer {
    padding: 1.5rem;
    border-top: 1px solid rgba(255,255,255,0.1);
}

.user-info {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 1rem;
}

.avatar {
    width: 40px;
    height: 40px;
    background: var(--primary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: bold;
    font-size: 1.2rem;
}

.user-details {
    font-size: 0.875rem;
    color: #94A3B8;
}

/* Main Content */
.main-content {
    flex: 1;
    padding: 2.5rem 3rem;
    max-width: calc(100vw - 280px);
    overflow-y: auto;
}

.page-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 2.5rem;
}

.page-title {
    font-size: 2rem;
    font-weight: 800;
    letter-spacing: -0.025em;
    color: var(--text-main);
}

/* Cards */
.card {
    background: var(--surface);
    border-radius: 1.25rem;
    box-shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.05), 0 8px 10px -6px rgba(0, 0, 0, 0.01);
    padding: 2rem;
    margin-bottom: 2.5rem;
    border: 1px solid var(--border);
}

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

.card-title {
    font-size: 1.25rem;
    font-weight: 700;
}

/* Upload Zone */
.upload-zone {
    border: 2px dashed #CBD5E1;
    border-radius: 1rem;
    padding: 3.5rem 2rem;
    text-align: center;
    background: #F8FAFC;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    cursor: pointer;
    display: block;
}

.upload-zone:hover {
    background: #EEF2FF;
    border-color: var(--primary);
    transform: scale(1.01);
}

.upload-icon {
    font-size: 3.5rem;
    margin-bottom: 1rem;
}

.upload-text {
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--text-main);
    margin-bottom: 0.5rem;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.6rem 1.2rem;
    font-weight: 600;
    font-size: 0.875rem;
    border-radius: 0.5rem;
    border: none;
    cursor: pointer;
    transition: all 0.2s;
    text-decoration: none;
    box-shadow: 0 4px 6px -1px rgba(0,0,0,0.1);
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-hover) 100%);
    color: white;
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 6px 12px rgba(99, 102, 241, 0.3); }

.btn-success {
    background: linear-gradient(135deg, var(--secondary) 0%, var(--secondary-hover) 100%);
    color: white;
}
.btn-success:hover { transform: translateY(-2px); box-shadow: 0 6px 12px rgba(16, 185, 129, 0.3); }

.btn-danger {
    background: linear-gradient(135deg, var(--danger) 0%, var(--danger-hover) 100%);
    color: white;
}
.btn-danger:hover { transform: translateY(-2px); box-shadow: 0 6px 12px rgba(239, 68, 68, 0.3); }

/* Table Styling Overrides */
.dataTables_wrapper .top { display: flex; justify-content: space-between; align-items: center; margin-bottom: 1rem; flex-wrap: wrap; gap: 1rem; }
.dt-buttons .dt-button { margin-right: 0.5rem; }
.dataTables_wrapper .dataTables_filter input {
    border: 1px solid var(--border);
    border-radius: 0.5rem;
    padding: 0.5rem 1rem;
    margin-left: 0.5rem;
    outline: none;
    transition: border-color 0.2s;
}
.dataTables_wrapper .dataTables_filter input:focus {
    border-color: var(--primary);
}
table.dataTable.display tbody tr.even>.sorting_1, table.dataTable.order-column.stripe tbody tr.even>.sorting_1 { background-color: transparent; }
table.dataTable.display tbody tr.odd>.sorting_1, table.dataTable.order-column.stripe tbody tr.odd>.sorting_1 { background-color: transparent; }
table.dataTable tbody tr { transition: background-color 0.2s; }
table.dataTable tbody tr:hover { background-color: #F1F5F9 !important; }

/* Badges */
.status-badge {
    padding: 0.35rem 0.85rem;
    border-radius: 2rem;
    font-size: 0.75rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}
.status-success { background: #D1FAE5; color: #065F46; }
.status-pending { background: #FEF3C7; color: #92400E; }
.status-failed { background: #FEE2E2; color: #991B1B; }

/* Alerts */
.alert { padding: 1.25rem; border-radius: 0.75rem; margin-bottom: 2rem; font-weight: 500; display: flex; align-items: center; gap: 1rem; }
.alert-success { background: #ECFDF5; color: #065F46; border-left: 4px solid var(--secondary); }
.alert-warning { background: #FFFBEB; color: #92400E; border-left: 4px solid #F59E0B; }
.alert-danger { background: #FEF2F2; color: #991B1B; border-left: 4px solid var(--danger); }

/* Auth page */
.auth-container { min-height: 100vh; display: flex; align-items: center; justify-content: center; background: url('https://images.unsplash.com/photo-1436491865332-7a61a109cc05?q=80&w=2074&auto=format&fit=crop') center/cover; position: relative; }
.auth-container::before { content: ''; position: absolute; inset: 0; background: rgba(15, 23, 42, 0.7); backdrop-filter: blur(8px); }
.auth-card { position: relative; background: rgba(255,255,255,0.95); padding: 3rem; border-radius: 1.5rem; box-shadow: 0 25px 50px -12px rgba(0,0,0,0.25); width: 100%; max-width: 420px; z-index: 10; }
.auth-header h1 { font-size: 1.875rem; color: #0F172A; margin-bottom: 0.5rem; }
.form-control { width: 100%; padding: 0.875rem 1rem; border: 1px solid #CBD5E1; border-radius: 0.5rem; transition: all 0.2s; background: #F8FAFC; }
.form-control:focus { background: white; border-color: var(--primary); box-shadow: 0 0 0 4px rgba(99,102,241,0.1); }