.time-result {
            padding: 1rem 1.5rem;
            background: white;
            border-radius: 8px;
            border: 1px solid #e9ecef;
            font-family: 'Courier New', monospace;
            font-size: 2rem;
            text-align: center;
            margin: 0.5rem 0;
        }
        .time-unit-badge {
            background: rgba(70, 130, 180, 0.08);
            border-radius: 20px;
            padding: 0.2rem 0.8rem;
            font-size: 0.85rem;
            font-weight: 500;
            color: var(--primary-color);
        }
        .time-example-grid {
            display: flex;
            flex-wrap: wrap;
            gap: 0.6rem;
            margin: 1rem 0;
        }
        .time-example-btn {
            background: #f1f5f9;
            border: 1px solid #dee2e6;
            border-radius: 6px;
            padding: 0.4rem 0.9rem;
            font-size: 0.85rem;
            cursor: pointer;
            transition: all 0.2s;
            color: #1e293b;
        }
        .time-example-btn:hover {
            background: #e2e8f0;
            transform: translateY(-2px);
            box-shadow: 0 2px 6px rgba(0,0,0,0.06);
        }
        .timeline-canvas {
            width: 100%;
            height: 80px;
            background: #f8fafc;
            border-radius: 8px;
            border: 1px solid #e2e8f0;
            display: block;
            margin: 0.8rem 0;
        }
        .time-conversion-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
            gap: 0.5rem;
            margin: 1rem 0;
        }
        .time-conversion-card {
            background: #f8fafc;
            border-radius: 6px;
            padding: 0.6rem 0.8rem;
            text-align: center;
            border: 1px solid #e9ecef;
        }
        .time-conversion-card .value {
            font-weight: 700;
            font-size: 1.2rem;
            color: var(--primary-color);
        }
        .time-conversion-card .label {
            font-size: 0.75rem;
            color: #6c757d;
            text-transform: uppercase;
            letter-spacing: 0.03em;
        }
        .mode-tabs .nav-link {
            color: var(--text-color);
            border-radius: 6px 6px 0 0;
        }
        .mode-tabs .nav-link.active {
            background: var(--primary-color);
            color: white;
            border-color: var(--primary-color);
        }
        .math-notation {
            font-family: 'Cambria Math', 'Latin Modern Math', STIXGeneral, serif;
            font-size: 1.1rem;
        }
        .property-table {
            width: 100%;
            border-collapse: collapse;
            margin: 1.5rem 0;
        }
        .property-table th, .property-table td {
            padding: 0.75rem;
            text-align: left;
            border: 1px solid var(--border-color);
        }
        .property-table th {
            background: var(--light-gray);
            font-weight: 600;
        }
        .property-table tr:nth-child(even) {
            background: rgba(70, 130, 180, 0.04);
        }
        .authority-note {
            font-size: 0.85rem;
            color: var(--text-muted);
            border-top: 1px solid var(--border-color);
            padding-top: 1rem;
            margin-top: 1rem;
            text-align: right;
        }
        .case-study {
            background: #f0f7fa;
            border-radius: 8px;
            padding: 1.5rem;
            margin: 1.5rem 0;
            border-left: 5px solid var(--primary-color);
        }
        .key-point {
            font-weight: 500;
            color: var(--accent-color);
        }
        .math-box {
            background: rgba(70, 130, 180, 0.05);
            border-left: 3px solid var(--primary-color);
            padding: 1rem 1.2rem;
            border-radius: 0 4px 4px 0;
            margin: 1.5rem 0;
        }
        .privacy-note {
            font-size: 0.9rem;
            background: #e7f3ff;
            border: 1px solid #b8daff;
            color: #004085;
            padding: 0.5rem 1rem;
            border-radius: 4px;
            margin: 1rem 0;
        }
        .warning-note {
            background: #fff3cd;
            border: 1px solid #ffeeba;
            color: #856404;
            padding: 0.5rem 1rem;
            border-radius: 4px;
            margin: 1rem 0;
        }
        .author-bio {
            background: #f8f9fa;
            border-left: 4px solid var(--primary-color);
            padding: 1.2rem 1.5rem;
            margin: 2rem 0;
            border-radius: 0 8px 8px 0;
        }
        .unit-note {
            font-size: 0.9rem;
            color: #6c757d;
        }
        .legend-timeline {
            display: flex;
            justify-content: center;
            gap: 2rem;
            margin: 0.3rem 0 0.8rem 0;
            font-size: 0.85rem;
        }
        .legend-timeline .dot {
            display: inline-block;
            width: 14px;
            height: 14px;
            border-radius: 50%;
            margin-right: 0.3rem;
        }
        .legend-timeline .dot.start { background: #28a745; }
        .legend-timeline .dot.end { background: #dc3545; }
        .legend-timeline .dot.duration { background: #0d6efd; }
        .subsection-title {
            font-weight: 600;
            margin-top: 2rem;
            margin-bottom: 1rem;
            color: var(--accent-color);
            font-size: 1.2rem;
        }
        .deep-dive p {
            text-align: justify;
        }
        .time-input-group {
            display: flex;
            flex-wrap: wrap;
            gap: 0.5rem;
            align-items: center;
        }
        .time-input-group .form-control {
            width: 80px;
            display: inline-block;
        }
        @media (min-width: 576px) {
            .time-input-group .form-control {
                width: 100px;
            }
        }
        .result-row {
            font-size: 1.1rem;
            margin: 0.4rem 0;
        }
        .result-value {
            font-weight: 600;
            color: var(--primary-color);
        }
        .badge-time {
            background: rgba(13, 110, 253, 0.12);
            color: #0d6efd;
            font-weight: 500;
            padding: 0.3rem 0.8rem;
            border-radius: 20px;
            font-size: 0.85rem;
        }