body { font-family: 'Inter', sans-serif; }
        .chart-container { position: relative; width: 100%; max-width: 500px; margin-left: auto; margin-right: auto; height: 300px; max-height: 40vh; }
        @media (min-width: 768px) { .chart-container { height: 350px; } }
        .section-hidden { display: none; }
        .timeline-item .timeline-content {
            transform: translateX(1.5rem);
            opacity: 0;
            transition: transform 0.4s ease-out, opacity 0.4s ease-out;
        }
        .timeline-item.active .timeline-content {
            transform: translateX(0);
            opacity: 1;
        }
        .nav-link.active {
            border-color: #3b82f6; /* blue-500 */
            color: #3b82f6;
            background-color: #eff6ff; /* blue-50 */
        }
        .nav-link {
            transition: all 0.2s ease-in-out;
        }