/* ===== Tokens ===== */
:root {
    --ink: #1F2937;
    --ink-soft: #4B5563;
    --muted: #6B7280;
    --hairline: #E5E7EB;
    --accent: #8B6F47;
    --navy: #1F2A44;
    --bg: #FFFFFF;
}

/* ===== Base ===== */
body, html {
    margin: 0;
    padding: 0;
    scroll-behavior: smooth;
    font-family: 'Inter', 'Helvetica Neue', Arial, sans-serif;
    font-weight: 400;
    background-color: var(--bg);
    color: var(--ink);
    width: 100%;
    min-width: 320px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

h1, h2, h3, .serif {
    font-family: 'Crimson Pro', 'EB Garamond', Georgia, serif;
    color: var(--ink);
    font-weight: 600;
    letter-spacing: -0.01em;
}

h1 {
    font-size: 2.4rem;
    margin: 0 0 24px 0;
    line-height: 1.15;
}

h3 {
    font-size: 1.35rem;
    line-height: 1.3;
    margin: 0 0 4px 0;
    font-weight: 600;
}

p {
    font-size: 1.02rem;
    line-height: 1.55;
    color: var(--ink);
    margin: 0.35em 0;
}

a {
    font-size: 1.02rem;
    color: var(--ink);
    text-decoration: none;
    border-bottom: 1px solid var(--hairline);
    transition: border-color 0.15s, color 0.15s;
}

a:hover {
    color: var(--accent);
    border-bottom-color: var(--accent);
}

section {
    padding: 64px 24px 48px;
    scroll-margin-top: 70px;
    max-width: 1100px;
    margin: 0 auto;
}

img {
    width: 100%;
    height: auto;
    border-radius: 4px;
}

/* ===== Section architecture ===== */
.section-divider {
    border: 0;
    border-top: 1px solid var(--hairline);
    width: 60px;
    margin: 0 0 18px 0;
}

.section-kicker {
    font-family: 'Inter', sans-serif;
    font-size: 0.72rem;
    letter-spacing: 0.18em;
    text-transform: uppercase;
    color: var(--muted);
    margin: 0 0 6px 0;
    font-weight: 500;
}

/* ===== Navbar ===== */
.navbar {
    position: fixed;
    top: 0;
    width: 100%;
    background-color: var(--navy);
    z-index: 10;
    display: flex;
    justify-content: center;
    gap: 8px;
    box-shadow: 0 1px 0 rgba(0,0,0,0.06);
}

.navbar a {
    color: #E5E7EB;
    padding: 18px 16px;
    text-decoration: none;
    border-bottom: none;
    font-size: 0.92rem;
    letter-spacing: 0.02em;
    transition: color 0.15s;
}

.navbar a:hover {
    color: #FFFFFF;
    border-bottom: none;
}

.hamburger {
    display: none;
    background-color: var(--navy);
    color: #FFFFFF;
    border: none;
    padding: 18px;
    font-size: 22px;
    cursor: pointer;
}

.top-link {
    display: inline-block;
    margin: 24px 0 0 0;
    padding: 0;
    font-size: 0.85rem;
    color: var(--muted);
    border-bottom: 1px solid transparent;
    background: none;
    text-transform: lowercase;
    letter-spacing: 0.05em;
}

.top-link:hover {
    color: var(--accent);
    border-bottom-color: var(--accent);
}

/* ===== Home section ===== */
#home {
    padding-top: 110px;
}

.container_a {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 40px;
    padding: 20px 0;
}

.photo_a {
    flex: 0 0 240px;
    max-width: 240px;
}

.photo_a img {
    border-radius: 6px;
}

.about_a {
    flex: 1 1 380px;
    text-align: left;
    padding: 0;
    background: none;
    border-left: 2px solid var(--hairline);
    padding-left: 24px;
}

.about_a h1 {
    margin-top: 0;
}

.contact-icon {
    display: flex;
    gap: 14px;
    flex-wrap: wrap;
    margin-top: 18px;
}

.contact-icon a {
    text-decoration: none;
    border: none;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 32px;
    height: 32px;
    opacity: 0.85;
    transition: opacity 0.15s;
}

.contact-icon a:hover { opacity: 1; }

.contact-icon img,
.contact-icon svg {
    width: 28px;
    height: 28px;
    border-radius: 4px;
}

.contact-icon svg { fill: var(--ink); }

/* ===== Publications / Working papers ===== */
.publication, .wp {
    padding: 18px 0;
    border-bottom: 1px solid var(--hairline);
    width: 100%;
    box-sizing: border-box;
}

.publication:last-of-type,
.wp:last-of-type {
    border-bottom: none;
}

.pub-meta {
    color: var(--ink-soft);
    font-size: 0.95rem;
    margin: 2px 0;
}

.pub-venue {
    color: var(--ink);
    font-size: 0.98rem;
    margin: 2px 0 6px 0;
}

.pub-links {
    font-size: 0.92rem;
    margin: 6px 0;
}

.pub-links a {
    font-size: 0.92rem;
    margin-right: 14px;
    color: var(--ink-soft);
    border-bottom: 1px solid var(--hairline);
}

.pub-links a:hover {
    color: var(--accent);
    border-bottom-color: var(--accent);
}

/* ===== Toggleable abstracts ===== */
details.abstract {
    margin-top: 8px;
    font-size: 0.96rem;
}

details.abstract summary {
    cursor: pointer;
    color: var(--muted);
    font-size: 0.85rem;
    letter-spacing: 0.05em;
    text-transform: uppercase;
    list-style: none;
    display: inline-flex;
    align-items: center;
    user-select: none;
    padding: 2px 0;
}

details.abstract summary::-webkit-details-marker { display: none; }

details.abstract summary::before {
    content: "▸";
    display: inline-block;
    margin-right: 6px;
    font-size: 0.7rem;
    transition: transform 0.15s;
}

details.abstract[open] summary::before {
    transform: rotate(90deg);
}

details.abstract summary:hover { color: var(--accent); }

details.abstract .abstract-body {
    color: var(--ink-soft);
    line-height: 1.6;
    margin-top: 10px;
    padding-left: 14px;
    border-left: 2px solid var(--hairline);
    font-size: 0.96rem;
    max-width: 70ch;
    text-align: justify;
    text-justify: inter-word;
    hyphens: auto;
    -webkit-hyphens: auto;
}

/* ===== Per-paper theme tags ===== */
.pub-tags {
    margin: 4px 0 8px 0;
    line-height: 1.8;
}

.pub-tag {
    display: inline-block;
    font-family: 'Inter', sans-serif;
    font-size: 0.7rem;
    letter-spacing: 0.08em;
    text-transform: lowercase;
    font-weight: 500;
    padding: 2px 9px;
    border-radius: 3px;
    margin-right: 5px;
    vertical-align: 1px;
}

.pub-tag-inst { background: #E9ECF1; color: #4A5568; }
.pub-tag-dev  { background: #ECEFE4; color: #5A6B43; }
.pub-tag-beh  { background: #F2ECDD; color: #7A5F33; }

/* ===== Teaching / Media rows ===== */
.row {
    display: flex;
    margin-bottom: 24px;
    flex-wrap: wrap;
    border-bottom: 1px solid var(--hairline);
    padding-bottom: 18px;
}

.row:last-child { border-bottom: none; }

.column-header, .column-content {
    flex: 1;
    padding: 0 10px 0 0;
}

.column-content { flex: 3; }

.column-header h3 {
    margin: 0;
    color: var(--ink);
    font-family: 'Crimson Pro', Georgia, serif;
    font-size: 1.1rem;
}

.column-content p {
    margin: 4px 0;
    color: var(--ink-soft);
}

.column-content a { font-size: 1rem; }

/* ===== YouTube iframe inside publication ===== */
.publication iframe {
    max-width: 100%;
    margin-top: 12px;
    border-radius: 4px;
}

/* ===== Responsive ===== */
@media (max-width: 768px) {
    .navbar { justify-content: flex-start; }
    .navbar a { display: none; }
    .hamburger { display: block; }
    .navbar {
        flex-direction: column;
        align-items: flex-start;
    }
    .navbar.responsive {
        display: flex;
        flex-direction: column;
        align-items: flex-start;
    }
    .navbar.responsive a {
        display: block;
        padding: 10px 18px;
        text-align: left;
    }
    .column-header, .column-content { flex: 1 1 100%; }
    h1 { font-size: 2rem; }
}

@media (max-width: 600px) {
    .container_a { flex-direction: column; gap: 24px; }
    .photo_a {
        flex: 0 0 auto;
        max-width: 200px;
    }
    .about_a {
        border-left: none;
        padding-left: 0;
        border-top: 1px solid var(--hairline);
        padding-top: 20px;
    }
}