:root {
    --bg-main: #f8fafc;
    --bg-card: #ffffff;
    --border-color: #e2e8f0;
    --border-focus: #b8860b;
    --text-primary: #0f172a;
    --text-secondary: #475569;
    --text-muted: #64748b;
    
    --primary-color: #0f172a;
    --primary-hover: #1e293b;
    --gold-color: #b8860b;
    --gold-hover: #966c06;
    --gold-light: #fefce8;
    --gold-border: #fde047;

    --success-bg: #f0fdf4;
    --success-text: #166534;
    --success-border: #bbf7d0;

    --error-bg: #fef2f2;
    --error-text: #991b1b;
    --error-border: #fecaca;

    --border-radius: 12px;
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 14px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 30px rgba(0, 0, 0, 0.08);
}

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

body {
    font-family: 'Inter', system-ui, -apple-system, sans-serif;
    background-color: var(--bg-main);
    color: var(--text-primary);
    line-height: 1.5;
    -webkit-font-smoothing: antialiased;
}

.app-container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 24px;
}

/* Header */
.main-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 28px;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    margin-bottom: 20px;
    box-shadow: var(--shadow-sm);
}

.brand-title {
    display: flex;
    align-items: center;
    gap: 16px;
}

.brand-icon {
    width: 44px;
    height: 44px;
    border-radius: 10px;
    background: #0f172a;
    color: #d4af37;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 20px;
    font-weight: 700;
    border: 1px solid #d4af37;
}

.brand-title h1 {
    font-size: 20px;
    font-weight: 700;
    color: var(--text-primary);
    letter-spacing: -0.3px;
}

.brand-title p {
    font-size: 13px;
    color: var(--text-secondary);
    font-weight: 500;
}

/* Tab Navigation Bar */
.nav-tabs {
    display: flex;
    gap: 8px;
    background: #ffffff;
    padding: 8px 12px;
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    margin-bottom: 24px;
    box-shadow: var(--shadow-sm);
}

.nav-tab-btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 10px 18px;
    border-radius: 8px;
    border: 1px solid transparent;
    background: transparent;
    color: var(--text-secondary);
    font-weight: 600;
    font-size: 14px;
    cursor: pointer;
    transition: all 0.2s ease;
}

.nav-tab-btn:hover {
    color: var(--text-primary);
    background: #f1f5f9;
}

.nav-tab-btn.active {
    background: #0f172a;
    color: #ffffff;
    border-color: #0f172a;
}

.nav-tab-badge {
    background: rgba(255, 255, 255, 0.2);
    padding: 2px 8px;
    border-radius: 12px;
    font-size: 11px;
}

.nav-tab-btn:not(.active) .nav-tab-badge {
    background: #e2e8f0;
    color: var(--text-secondary);
}

/* Layout Grid */
.module-layout {
    display: grid;
    grid-template-columns: 420px 1fr;
    gap: 24px;
}

@media (max-width: 1024px) {
    .module-layout {
        grid-template-columns: 1fr;
    }
}

.white-panel {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    padding: 24px;
    box-shadow: var(--shadow-sm);
}

.panel-title {
    font-size: 16px;
    font-weight: 700;
    margin-bottom: 20px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    color: var(--text-primary);
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 12px;
}

/* Form Controls */
.form-group {
    margin-bottom: 16px;
}

.form-group label {
    display: block;
    font-size: 13px;
    font-weight: 600;
    color: var(--text-secondary);
    margin-bottom: 6px;
}

.form-control {
    width: 100%;
    padding: 10px 14px;
    background: #ffffff;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    color: var(--text-primary);
    font-size: 14px;
    outline: none;
    transition: all 0.2s ease;
}

.form-control:focus {
    border-color: var(--border-focus);
    box-shadow: 0 0 0 3px rgba(184, 134, 11, 0.12);
}

textarea.form-control {
    resize: vertical;
    min-height: 90px;
    font-family: 'Inter', monospace;
}

.btn-primary {
    width: 100%;
    padding: 12px 18px;
    background: var(--primary-color);
    color: #ffffff;
    font-weight: 600;
    font-size: 14px;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.2s ease;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
}

.btn-primary:hover {
    background: var(--primary-hover);
}

.btn-gold {
    background: var(--gold-color);
    color: #ffffff;
}

.btn-gold:hover {
    background: var(--gold-hover);
}

.btn-outline {
    background: #ffffff;
    border: 1px solid var(--border-color);
    color: var(--text-primary);
    padding: 10px 16px;
    border-radius: 8px;
    font-weight: 600;
    font-size: 13.5px;
    cursor: pointer;
    transition: all 0.15s ease;
}

.btn-outline:hover {
    background: #f8fafc;
    border-color: #cbd5e1;
}

.btn-icon {
    padding: 6px 12px;
    border-radius: 6px;
    border: 1px solid var(--border-color);
    background: #ffffff;
    color: var(--text-primary);
    font-size: 12px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.15s ease;
    display: inline-flex;
    align-items: center;
    gap: 6px;
}

.btn-icon:hover {
    background: #f8fafc;
    border-color: #cbd5e1;
}

.btn-danger {
    background: #fef2f2;
    color: #991b1b;
    border-color: #fecaca;
}

.btn-danger:hover {
    background: #fee2e2;
    border-color: #fca5a5;
}

.btn-success {
    background: #f0fdf4;
    color: #166534;
    border-color: #bbf7d0;
}

.btn-success:hover {
    background: #dcfce7;
}

/* Drag & Drop Zone */
.drop-zone {
    border: 2px dashed #cbd5e1;
    border-radius: 12px;
    padding: 32px 20px;
    text-align: center;
    background: #ffffff;
    cursor: pointer;
    transition: all 0.2s ease;
    margin-bottom: 20px;
}

.drop-zone:hover, .drop-zone.drag-over {
    border-color: var(--gold-color);
    background: var(--gold-light);
}

.drop-zone-icon {
    font-size: 32px;
    margin-bottom: 8px;
    color: var(--gold-color);
}

/* Certificate Preview Frame */
.cert-preview-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 20px;
}

.cert-frame {
    width: 100%;
    max-width: 850px;
    background: #ffffff;
    border-radius: 12px;
    padding: 8px;
    border: 1px solid var(--border-color);
    box-shadow: var(--shadow-md);
    overflow: hidden;
}

.action-row {
    display: flex;
    gap: 12px;
    width: 100%;
    max-width: 850px;
}

/* Table Styling */
.custom-table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 8px;
    font-size: 13.5px;
}

.custom-table th, .custom-table td {
    padding: 12px 16px;
    text-align: left;
    border-bottom: 1px solid var(--border-color);
}

.custom-table th {
    color: var(--text-muted);
    font-weight: 600;
    text-transform: uppercase;
    font-size: 11px;
    letter-spacing: 0.5px;
    background: #f8fafc;
}

.custom-table tr:hover {
    background: #f8fafc;
}

.badge {
    padding: 4px 8px;
    border-radius: 6px;
    font-size: 11.5px;
    font-weight: 600;
    background: #f1f5f9;
    color: var(--text-primary);
    border: 1px solid #e2e8f0;
}

.badge-success {
    background: var(--success-bg);
    color: var(--success-text);
    border: 1px solid var(--success-border);
}

.badge-failed {
    background: var(--error-bg);
    color: var(--error-text);
    border: 1px solid var(--error-border);
}

/* Modal Overlay */
.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(15, 23, 42, 0.4);
    backdrop-filter: blur(4px);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    padding: 20px;
}

.modal-card {
    background: #ffffff;
    border-radius: 16px;
    border: 1px solid var(--border-color);
    box-shadow: var(--shadow-lg);
    width: 100%;
    max-width: 560px;
    padding: 28px;
    animation: modalAppear 0.2s ease-out;
}

@keyframes modalAppear {
    from { opacity: 0; transform: scale(0.95); }
    to { opacity: 1; transform: scale(1); }
}

.filter-bar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 16px;
    flex-wrap: wrap;
    margin-bottom: 16px;
}

.filter-pills {
    display: flex;
    gap: 6px;
}

.filter-pill {
    padding: 6px 14px;
    border-radius: 20px;
    border: 1px solid var(--border-color);
    background: #ffffff;
    color: var(--text-secondary);
    font-size: 12.5px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.15s ease;
}

.filter-pill.active {
    background: #0f172a;
    color: #ffffff;
    border-color: #0f172a;
}