:root {
    --primary-color: #2563eb;
    --secondary-color: #64748b;
    --success-color: #10b981;
    --danger-color: #ef4444;
    --warning-color: #f59e0b;
    --info-color: #3b82f6;
    --dark-bg: #0f172a;
    --card-bg: #1e293b;
    --border-color: #334155;
    --text-primary: #f1f5f9;
    --text-secondary: #94a3b8;
    --hover-bg: #334155;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: linear-gradient(135deg, #0f172a 0%, #1e293b 100%);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
}

.navbar {
    background: rgba(15, 23, 42, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color);
    padding: 1rem 0;
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

.navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-brand h1 {
    font-size: 1.5rem;
    color: var(--primary-color);
    margin-bottom: 0.25rem;
}

.nav-brand .subtitle {
    font-size: 0.875rem;
    color: var(--text-secondary);
}

.nav-links {
    display: flex;
    gap: 1rem;
}

.nav-link {
    color: var(--text-secondary);
    text-decoration: none;
    padding: 0.5rem 1rem;
    border-radius: 0.5rem;
    transition: all 0.3s ease;
    font-weight: 500;
}

.nav-link:hover {
    color: var(--text-primary);
    background: var(--hover-bg);
}

.nav-link.active {
    color: var(--primary-color);
    background: rgba(37, 99, 235, 0.1);
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1.5rem;
}

main.container {
    padding: 2rem 1.5rem;
}

.section {
    display: none;
    animation: fadeIn 0.3s ease;
}

.section.active {
    display: block;
}

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

.section-header {
    margin-bottom: 2rem;
}

.section-header h2 {
    font-size: 2rem;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
}

.section-header p {
    color: var(--text-secondary);
    font-size: 1.125rem;
}

.card {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 0.75rem;
    margin-bottom: 1.5rem;
    overflow: hidden;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.card:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 12px rgba(0, 0, 0, 0.2);
}

.card-header {
    padding: 1.25rem 1.5rem;
    border-bottom: 1px solid var(--border-color);
    background: rgba(30, 41, 59, 0.5);
}

.card-header h3 {
    font-size: 1.25rem;
    color: var(--text-primary);
}

.card-body {
    padding: 1.5rem;
}

.form-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.25rem;
}

.form-group {
    display: flex;
    flex-direction: column;
}

.form-group label {
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--text-secondary);
    margin-bottom: 0.5rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.form-group input,
.form-group select {
    padding: 0.75rem;
    background: var(--dark-bg);
    border: 1px solid var(--border-color);
    border-radius: 0.5rem;
    color: var(--text-primary);
    font-size: 1rem;
    transition: all 0.3s ease;
}

.form-group input:focus,
.form-group select:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.form-group input:hover,
.form-group select:hover {
    border-color: var(--primary-color);
}

.btn {
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: 0.5rem;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    text-decoration: none;
}

.btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
}

.btn:active {
    transform: translateY(0);
}

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

.btn-primary:hover {
    background: #1d4ed8;
}

.btn-success {
    background: var(--success-color);
    color: white;
}

.btn-success:hover {
    background: #059669;
}

.btn-danger {
    background: var(--danger-color);
    color: white;
}

.btn-danger:hover {
    background: #dc2626;
}

.btn-secondary {
    background: var(--secondary-color);
    color: white;
}

.btn-secondary:hover {
    background: #475569;
}

.button-group {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
    margin-bottom: 1.5rem;
}

.drives-container {
    display: grid;
    gap: 1.5rem;
    margin-bottom: 1.5rem;
}

.drive-card {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 0.75rem;
    padding: 1.5rem;
    position: relative;
}

.drive-card-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
}

.drive-card-header h4 {
    color: var(--primary-color);
    font-size: 1.125rem;
}

.config-preview {
    background: var(--dark-bg);
    border: 1px solid var(--border-color);
    border-radius: 0.5rem;
    padding: 1.5rem;
    color: var(--text-primary);
    font-family: 'Courier New', monospace;
    font-size: 0.875rem;
    overflow-x: auto;
    white-space: pre-wrap;
    line-height: 1.5;
}

.alert {
    padding: 1rem 1.25rem;
    border-radius: 0.5rem;
    margin-top: 1rem;
    border-left: 4px solid;
}

.alert-info {
    background: rgba(59, 130, 246, 0.1);
    border-color: var(--info-color);
    color: var(--text-primary);
}

.alert-success {
    background: rgba(16, 185, 129, 0.1);
    border-color: var(--success-color);
    color: var(--text-primary);
}

.alert-warning {
    background: rgba(245, 158, 11, 0.1);
    border-color: var(--warning-color);
    color: var(--text-primary);
}

.alert-danger {
    background: rgba(239, 68, 68, 0.1);
    border-color: var(--danger-color);
    color: var(--text-primary);
}

.footer {
    background: rgba(15, 23, 42, 0.95);
    border-top: 1px solid var(--border-color);
    padding: 2rem 0;
    margin-top: 4rem;
    text-align: center;
}

.footer p {
    color: var(--text-secondary);
    font-size: 0.875rem;
}

.footer a {
    color: var(--primary-color);
    text-decoration: none;
    transition: color 0.3s ease;
}

.footer a:hover {
    color: #1d4ed8;
}

.tape-table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 1rem;
}

.tape-table th,
.tape-table td {
    padding: 0.75rem;
    text-align: left;
    border-bottom: 1px solid var(--border-color);
}

.tape-table th {
    background: rgba(37, 99, 235, 0.1);
    color: var(--primary-color);
    font-weight: 600;
    text-transform: uppercase;
    font-size: 0.875rem;
    letter-spacing: 0.05em;
}

.tape-table tbody tr {
    transition: background-color 0.2s;
}

.tape-table tbody tr:hover {
    background: var(--hover-bg);
}

.tape-table .tape-barcode {
    font-family: 'Courier New', monospace;
    font-weight: 600;
    color: var(--info-color);
}

.tape-table .tape-size {
    color: var(--text-secondary);
}

.tape-table .tape-date {
    color: var(--text-secondary);
    font-size: 0.875rem;
}

.tape-actions {
    display: flex;
    gap: 0.5rem;
}

.btn-small {
    padding: 0.375rem 0.75rem;
    font-size: 0.875rem;
}

@media (max-width: 768px) {
    .navbar .container {
        flex-direction: column;
        gap: 1rem;
    }

    .nav-links {
        width: 100%;
        justify-content: center;
        flex-wrap: wrap;
    }

    .form-grid {
        grid-template-columns: 1fr;
    }

    .button-group {
        flex-direction: column;
    }

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

    .tape-table {
        font-size: 0.875rem;
    }
}

/* Library Visualizer Styles */
.library-viz {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.viz-section h4 {
    margin-bottom: 0.75rem;
    color: var(--text-secondary);
    text-transform: uppercase;
    font-size: 0.875rem;
    letter-spacing: 0.05em;
}

.viz-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(100px, 1fr));
    gap: 0.75rem;
}

.viz-slot {
    background: var(--dark-bg);
    border: 1px solid var(--border-color);
    border-radius: 0.5rem;
    padding: 0.75rem 0.5rem;
    text-align: center;
    transition: all 0.2s;
    cursor: default;
    position: relative;
    box-shadow: 0 1px 2px rgba(0,0,0,0.1);
}

.viz-slot:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 6px rgba(0,0,0,0.2);
}

.viz-slot.full {
    background: rgba(16, 185, 129, 0.1);
    border-color: var(--success-color);
}

.viz-slot .slot-icon {
    font-size: 1.5rem;
    margin-bottom: 0.25rem;
    display: block;
}

.viz-slot .slot-id {
    font-size: 0.75rem;
    color: var(--text-secondary);
    margin-bottom: 0.25rem;
    font-weight: 500;
}

.viz-slot .tape-label {
    font-size: 0.75rem;
    font-weight: 600;
    font-family: 'Courier New', monospace;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    color: var(--text-secondary);
}

.viz-slot.full .tape-label {
    color: var(--success-color);
}

.viz-slot.empty .tape-label {
    color: var(--text-secondary);
    font-style: italic;
    opacity: 0.5;
}

/* Drive specific styling */
.drive-slot {
    border-color: var(--info-color);
}

.drive-slot.full {
    background: rgba(59, 130, 246, 0.1);
    border-color: var(--info-color);
}

.drive-slot.full .tape-label {
    color: var(--info-color);
}