/* ── Section Jump Navigation ────────────────────────────────────────── */

.section-nav {
    position: sticky;
    top: 0;
    z-index: 100;
    background: #ffffff;
    border-bottom: 1px solid #e2e8f0;
    box-shadow: 0 1px 4px rgba(0, 0, 0, 0.06);
}

.nav-inner {
    max-width: 1440px;
    margin: 0 auto;
    padding: 0 18px;
    display: flex;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    scrollbar-width: none;
}

.nav-inner::-webkit-scrollbar {
    display: none;
}

.nav-link {
    color: #475569;
    text-decoration: none;
    font-size: 0.875rem;
    font-weight: 500;
    padding: 10px 14px;
    white-space: nowrap;
    display: block;
    border-bottom: 2px solid transparent;
    transition: color 0.15s, border-color 0.15s;
    flex-shrink: 0;
}

.nav-link:hover {
    color: #1e293b;
    border-bottom-color: #3b82f6;
}

/* Offset anchor targets so sticky nav doesn't obscure the section header */
[id^="section-"] {
    scroll-margin-top: 52px;
}

/* ── Responsive / Mobile Styles ────────────────────────────────────── */

/* dcc.Graph: always fill the card width */
.js-plotly-plot,
.plotly-graph-div {
    width: 100% !important;
}

/* About section: side-by-side on desktop, stacked on mobile */
.about-flex {
    display: flex;
    gap: 24px;
    align-items: flex-start;
}

@media (max-width: 640px) {
    .about-flex {
        flex-direction: column;
        align-items: center;
    }

    .about-image-col {
        margin-right: 0 !important;
        display: flex;
        flex-direction: column;
        align-items: center;
    }
}

/* Main content: tighter horizontal padding on small screens */
@media (max-width: 640px) {
    .main-content {
        padding-left: 10px !important;
        padding-right: 10px !important;
    }

    /* Header: reduce vertical padding */
    .site-header {
        padding: 12px 10px !important;
        margin-bottom: 16px !important;
    }

    /* Section headers: slightly smaller title */
    .site-header h1 {
        font-size: 1.15rem;
    }
}