/* Leuven Gravity Institute — site styles.
   The accent colour is injected inline from content/site.yaml (site.accent);
   everything else lives here. The institute voice is a serif display face for
   headings over a sans body, on a wider measure than a personal site would
   use, so listings of people, publications, and events have room to breathe. */

:root {
    --bg: #ffffff;
    --surface: #f6f8f9;
    --surface-strong: #eef2f4;
    --border: #dfe5e9;
    --text: #16212b;
    --muted: #5a6a78;
    --link: var(--accent);
    --accent-soft: color-mix(in srgb, var(--accent) 12%, transparent);
    --radius: 10px;
    --maxw: 1080px;
    --measure: 68ch;
    --serif:
        'Iowan Old Style', 'Palatino Linotype', Palatino, 'Book Antiqua',
        Georgia, serif;
    --sans:
        -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial,
        'Apple Color Emoji', 'Segoe UI Emoji', sans-serif;
}

:root[data-theme='dark'] {
    --bg: #0d1418;
    --surface: #141d23;
    --surface-strong: #1b262e;
    --border: #26333c;
    --text: #e4ebef;
    --muted: #96a6b3;
}

@media (prefers-color-scheme: dark) {
    :root:not([data-theme='light']) {
        --bg: #0d1418;
        --surface: #141d23;
        --surface-strong: #1b262e;
        --border: #26333c;
        --text: #e4ebef;
        --muted: #96a6b3;
    }
}

* {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    scroll-padding-top: 84px;
}

body {
    margin: 0;
    font-family: var(--sans);
    font-size: 17px;
    line-height: 1.65;
    color: var(--text);
    background: var(--bg);
    -webkit-font-smoothing: antialiased;
    overflow-wrap: break-word;
}

h1,
h2,
h3 {
    font-family: var(--serif);
    font-weight: 600;
    letter-spacing: -0.01em;
}

a {
    color: var(--link);
    text-decoration: none;
}
a:hover {
    text-decoration: underline;
}

.wrap {
    max-width: var(--maxw);
    margin: 0 auto;
    padding: 0 1.5rem;
}

.skip-link {
    position: absolute;
    left: -9999px;
}
.skip-link:focus {
    left: 1rem;
    top: 0.6rem;
    z-index: 20;
    background: var(--bg);
    border: 1px solid var(--accent);
    border-radius: 8px;
    padding: 0.4rem 0.8rem;
}

/* Masthead */
.masthead {
    position: sticky;
    top: 0;
    z-index: 10;
    background: color-mix(in srgb, var(--bg) 90%, transparent);
    backdrop-filter: saturate(180%) blur(10px);
    border-bottom: 1px solid var(--border);
}
.masthead-inner {
    max-width: var(--maxw);
    margin: 0 auto;
    padding: 0.7rem 1.5rem;
    display: flex;
    align-items: center;
    gap: 1.25rem;
}
.brand {
    display: flex;
    align-items: center;
    gap: 0.6rem;
    color: var(--text);
}
.brand:hover {
    text-decoration: none;
}
.brand-mark {
    display: inline-flex;
    width: 34px;
    height: 34px;
    flex: none;
}
.brand-mark img {
    width: 100%;
    height: 100%;
    display: block;
}
.brand-text {
    display: flex;
    flex-direction: column;
    line-height: 1.15;
}
.brand-name {
    font-family: var(--serif);
    font-weight: 600;
    font-size: 1.05rem;
}
.brand-tagline {
    font-size: 0.76rem;
    color: var(--muted);
}
.nav-links {
    display: flex;
    gap: 1.05rem;
    margin-left: auto;
    flex-wrap: wrap;
}
.nav-links a {
    color: var(--muted);
    font-size: 0.92rem;
}
.nav-links a:hover {
    color: var(--text);
    text-decoration: none;
}
.nav-links a.active {
    color: var(--text);
    font-weight: 600;
    box-shadow: inset 0 -2px 0 var(--accent);
}
.nav-actions {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}
.icon-button {
    background: none;
    border: 1px solid var(--border);
    color: var(--text);
    border-radius: 8px;
    width: 36px;
    height: 36px;
    cursor: pointer;
    font-size: 1rem;
    line-height: 1;
}
.icon-button:hover {
    background: var(--surface);
}
.nav-toggle {
    display: none;
    align-items: center;
    justify-content: center;
    font-size: 1.15rem;
}

/* Layout primitives */
main {
    min-height: 60vh;
}
.section {
    padding: 2.6rem 0;
    border-top: 1px solid var(--border);
}
main > .section:first-child,
.hero + .section {
    border-top: none;
}
.section-title {
    font-size: 1.5rem;
    margin: 0 0 1.3rem;
}
.group-heading {
    font-family: var(--sans);
    font-size: 0.78rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: var(--muted);
    margin: 1.9rem 0 0.8rem;
}
.group-heading:first-child {
    margin-top: 0;
}
.muted {
    color: var(--muted);
    font-size: 0.92rem;
}
.more {
    margin: 1.2rem 0 0;
}
.more a {
    font-weight: 600;
    font-size: 0.92rem;
}
.prose {
    max-width: var(--measure);
}
.prose-wide {
    max-width: 76ch;
}
.prose p {
    margin: 0 0 0.8rem;
}
.prose p:last-child {
    margin-bottom: 0;
}

/* Page header */
.page-header {
    padding: 2.8rem 0 0.4rem;
    background: linear-gradient(180deg, var(--accent-soft), transparent);
}
.page-title {
    font-size: 2.1rem;
    margin: 0;
}
.page-lead {
    margin: 0.6rem 0 0;
    color: var(--muted);
    max-width: var(--measure);
}
.page-header + .section {
    border-top: none;
    padding-top: 1.6rem;
}
.breadcrumb {
    margin: 1.6rem 0 0;
    font-size: 0.9rem;
}

/* Hero */
.hero {
    background:
        radial-gradient(
            110% 120% at 12% 0%,
            var(--accent-soft),
            transparent 60%
        ),
        var(--surface);
    border-bottom: 1px solid var(--border);
}
.hero-inner {
    padding-top: 3.6rem;
    padding-bottom: 3.2rem;
}
.hero-eyebrow {
    margin: 0 0 0.7rem;
    font-size: 0.78rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--accent);
}
.hero-headline {
    font-size: clamp(2.2rem, 5vw, 3.2rem);
    line-height: 1.1;
    margin: 0 0 1rem;
}
.hero-intro {
    max-width: var(--measure);
    font-size: 1.06rem;
}
.hero-intro p {
    margin: 0 0 0.8rem;
}
.facts {
    list-style: none;
    display: flex;
    flex-wrap: wrap;
    gap: 2.4rem;
    padding: 1.6rem 0 0;
    margin: 1.6rem 0 0;
    border-top: 1px solid var(--border);
}
.fact {
    display: flex;
    flex-direction: column;
}
.fact-value {
    font-family: var(--serif);
    font-size: 1.9rem;
    line-height: 1.1;
}
.fact-label {
    font-size: 0.78rem;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: var(--muted);
}

/* Buttons and pills */
.link-row {
    display: flex;
    flex-wrap: wrap;
    gap: 0.6rem;
    margin-top: 1.4rem;
}
.button {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    background: var(--accent);
    color: #fff;
    border-radius: 999px;
    padding: 0.5rem 1.1rem;
    font-size: 0.94rem;
    font-weight: 600;
}
.button:hover {
    text-decoration: none;
    filter: brightness(1.08);
}
.button .icon {
    width: 16px;
    height: 16px;
}
.button-quiet {
    background: transparent;
    color: var(--text);
    border: 1px solid var(--border);
}
.button-quiet:hover {
    border-color: var(--accent);
    filter: none;
}
.pill-link {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    border: 1px solid var(--border);
    border-radius: 999px;
    padding: 0.32rem 0.8rem;
    color: var(--text);
    font-size: 0.88rem;
}
.pill-link:hover {
    background: var(--surface);
    border-color: var(--accent);
    text-decoration: none;
}
.pill-link .icon {
    color: var(--muted);
    width: 16px;
    height: 16px;
}
.icon {
    display: inline-block;
    vertical-align: middle;
}

/* Tags and badges */
.tags {
    list-style: none;
    display: flex;
    flex-wrap: wrap;
    gap: 0.45rem;
    padding: 0;
    margin: 0.9rem 0;
}
.tag {
    background: var(--surface-strong);
    border-radius: 999px;
    padding: 0.15rem 0.65rem;
    font-size: 0.82rem;
    color: var(--muted);
}
.tags.small .tag {
    font-size: 0.76rem;
}
.badge {
    display: inline-block;
    font-size: 0.7rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--muted);
    border: 1px solid var(--border);
    border-radius: 6px;
    padding: 0.05rem 0.42rem;
    vertical-align: 0.12em;
}
.badge-dataset,
.badge-license {
    color: var(--accent);
    border-color: color-mix(in srgb, var(--accent) 45%, var(--border));
}

/* Cards */
.cards {
    list-style: none;
    display: grid;
    grid-template-columns: 1fr;
    gap: 1rem;
    padding: 0;
    margin: 0;
}
.cards-2 {
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
}
.card {
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 1.2rem 1.3rem;
    background: var(--surface);
    display: flex;
    flex-direction: column;
}
.card-title {
    margin: 0 0 0.5rem;
    font-size: 1.12rem;
}
.card-summary {
    margin: 0 0 0.6rem;
    font-size: 0.94rem;
}
.card-summary p {
    margin: 0 0 0.5rem;
}
.card-people,
.release-people {
    margin: 0.4rem 0 0;
    font-size: 0.88rem;
    color: var(--muted);
}
.card-links {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin: 0.7rem 0 0;
}
.card-links a {
    font-size: 0.82rem;
    border: 1px solid var(--border);
    border-radius: 6px;
    padding: 0.1rem 0.5rem;
    color: var(--muted);
}
.card-links a:hover {
    color: var(--accent);
    border-color: var(--accent);
    text-decoration: none;
}
.card-closed {
    opacity: 0.65;
}
.opening-level {
    margin: 0 0 0.3rem;
    font-size: 0.75rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: var(--accent);
}
.opening-deadline {
    margin: auto 0 0;
    padding-top: 0.6rem;
    font-size: 0.88rem;
    color: var(--muted);
}
.openings {
    margin: 1.4rem 0;
}

/* People */

/* Only rendered once the site covers more than one research group; it sits a
   level above the category headings, so it needs more weight than they carry. */
.people-group-heading {
    font-size: 1.35rem;
    margin: 2.4rem 0 0.4rem;
    padding-bottom: 0.4rem;
    border-bottom: 2px solid var(--accent);
}
.people-group-heading:first-child {
    margin-top: 0;
}

.person-grid {
    list-style: none;
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(230px, 1fr));
    gap: 0.9rem;
    padding: 0;
    margin: 0;
}
.person-card-link {
    display: flex;
    align-items: center;
    gap: 0.85rem;
    padding: 0.75rem;
    border: 1px solid var(--border);
    border-radius: var(--radius);
    background: var(--surface);
    color: var(--text);
    height: 100%;
}
.person-card-link:hover {
    text-decoration: none;
    border-color: var(--accent);
}
.person-card-photo {
    width: 60px;
    height: 60px;
    border-radius: 50%;
    object-fit: cover;
    background: var(--surface-strong);
    flex: none;
}
.person-card-body {
    display: flex;
    flex-direction: column;
    min-width: 0;
}
.person-card-name {
    font-weight: 600;
}
.person-card-role,
.person-card-meta {
    font-size: 0.85rem;
    color: var(--muted);
}
.person-card-meta {
    font-size: 0.78rem;
}
.alumni-list {
    list-style: none;
    padding: 0;
    margin: 0;
}
.alumni-item {
    padding: 0.4rem 0;
    border-bottom: 1px dashed var(--border);
}
.alumni-item:last-child {
    border-bottom: none;
}
.alumni-role {
    color: var(--muted);
    font-size: 0.9rem;
    margin-left: 0.5rem;
}

/* Person profile page */
.person-page {
    padding-bottom: 1rem;
}
.person-header {
    display: grid;
    grid-template-columns: 150px 1fr;
    gap: 1.8rem;
    align-items: start;
    padding: 1.6rem 0 2rem;
}
.person-photo {
    width: 150px;
    height: 150px;
    border-radius: 50%;
    object-fit: cover;
    border: 1px solid var(--border);
    background: var(--surface);
}
.person-name {
    font-size: 2rem;
    margin: 0 0 0.15rem;
}
.person-role {
    margin: 0;
    font-size: 1.08rem;
    font-weight: 600;
}
.person-period {
    margin: 0.15rem 0 0;
    color: var(--muted);
    font-size: 0.92rem;
}
.person-page .link-row {
    margin-top: 1rem;
}

/* Publications */
.year-heading {
    font-family: var(--sans);
    font-size: 0.95rem;
    font-weight: 700;
    color: var(--muted);
    margin: 1.8rem 0 0.5rem;
    padding-bottom: 0.3rem;
    border-bottom: 1px solid var(--border);
}
.pub-list {
    list-style: none;
    padding: 0;
    margin: 0;
}
.pub {
    padding: 0.75rem 0;
    border-bottom: 1px dashed var(--border);
    position: relative;
}
.pub:last-child {
    border-bottom: none;
}
.pub-highlight {
    padding-left: 1.5rem;
}
.pub .star {
    position: absolute;
    left: 0;
    top: 0.85rem;
    color: var(--accent);
}
.pub-title {
    margin: 0;
    font-weight: 600;
}
.pub-authors {
    margin: 0.15rem 0;
    font-size: 0.94rem;
}
.pub-venue {
    margin: 0.15rem 0;
    color: var(--muted);
    font-size: 0.9rem;
    font-style: italic;
}
.pub-type {
    font-style: normal;
    text-transform: uppercase;
    font-size: 0.68rem;
    letter-spacing: 0.05em;
    border: 1px solid var(--border);
    border-radius: 6px;
    padding: 0.05rem 0.4rem;
}
.pub-note {
    margin: 0.3rem 0 0;
    font-size: 0.88rem;
    color: var(--muted);
}
.pub-links {
    margin: 0.4rem 0 0;
    display: flex;
    flex-wrap: wrap;
    gap: 0.45rem;
}
.pub-links a {
    font-size: 0.8rem;
    border: 1px solid var(--border);
    border-radius: 6px;
    padding: 0.08rem 0.5rem;
    color: var(--muted);
}
.pub-links a:hover {
    color: var(--accent);
    border-color: var(--accent);
    text-decoration: none;
}
.pub-links .pub-member {
    border-style: dashed;
    color: var(--accent);
}

/* News */
.news-list {
    list-style: none;
    padding: 0;
    margin: 0;
}
.news-item {
    display: grid;
    grid-template-columns: 120px 1fr;
    gap: 1.2rem;
    padding: 0.85rem 0;
    border-bottom: 1px dashed var(--border);
}
.news-item:last-child {
    border-bottom: none;
}
.news-date {
    color: var(--muted);
    font-variant-numeric: tabular-nums;
    font-size: 0.9rem;
    padding-top: 0.15rem;
}
.news-title {
    margin: 0 0 0.2rem;
    font-weight: 600;
}

/* Events */
.event-list {
    list-style: none;
    padding: 0;
    margin: 0;
}
.event {
    display: grid;
    grid-template-columns: 76px 1fr;
    gap: 1.2rem;
    padding: 0.85rem 0;
    border-bottom: 1px dashed var(--border);
}
.event:last-child {
    border-bottom: none;
}
.event-date {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    border: 1px solid var(--border);
    border-radius: var(--radius);
    background: var(--surface);
    padding: 0.35rem 0;
    height: fit-content;
}
.event-day {
    font-family: var(--serif);
    font-size: 1.4rem;
    line-height: 1.1;
}
.event-month {
    font-size: 0.7rem;
    color: var(--muted);
    font-variant-numeric: tabular-nums;
}
.event-title {
    margin: 0;
    font-weight: 600;
}
.event-meta {
    margin: 0.1rem 0;
    color: var(--muted);
    font-size: 0.9rem;
}
.event-summary {
    margin: 0.25rem 0 0;
    font-size: 0.92rem;
}
.event-list-past {
    opacity: 0.78;
}

/* Software and data releases */
.release-list {
    list-style: none;
    padding: 0;
    margin: 0;
}
.release {
    padding: 0.85rem 0;
    border-bottom: 1px dashed var(--border);
}
.release:last-child {
    border-bottom: none;
}
.release-title {
    margin: 0;
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 0.4rem;
}
.release-name {
    font-weight: 600;
    font-size: 1.02rem;
}
.release-summary {
    margin: 0.2rem 0 0;
    font-size: 0.94rem;
    max-width: var(--measure);
}

/* Plain lists (teaching) */
.plain-list {
    list-style: none;
    padding: 0;
    margin: 0;
}
.plain-item {
    padding: 0.7rem 0;
    border-bottom: 1px dashed var(--border);
}
.plain-item:last-child {
    border-bottom: none;
}
.plain-main {
    display: block;
    font-weight: 600;
}
.plain-meta,
.plain-note {
    display: block;
    color: var(--muted);
    font-size: 0.9rem;
}
.plain-note {
    margin-top: 0.15rem;
    max-width: var(--measure);
}

/* Contact */
.contact-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
    margin-top: 1.6rem;
}
.contact-address {
    font-style: normal;
    color: var(--muted);
}
.contact-address p {
    margin: 0;
    white-space: pre-line;
}

/* Footer */
.footer {
    border-top: 1px solid var(--border);
    background: var(--surface);
    margin-top: 3rem;
    color: var(--muted);
    font-size: 0.9rem;
}
.footer-inner {
    max-width: var(--maxw);
    margin: 0 auto;
    padding: 2.2rem 1.5rem 1.2rem;
    display: flex;
    flex-wrap: wrap;
    gap: 1.2rem 2rem;
    justify-content: space-between;
}
.footer p {
    margin: 0;
}
.footer-name {
    font-family: var(--serif);
    font-size: 1.05rem;
    color: var(--text);
}
.footer-links {
    display: flex;
    flex-wrap: wrap;
    gap: 0.9rem;
    align-items: flex-start;
}
.footer-links a {
    display: inline-flex;
    align-items: center;
    gap: 0.35rem;
    color: var(--muted);
}
.footer-links a:hover {
    color: var(--text);
    text-decoration: none;
}
.footer-links .icon {
    width: 16px;
    height: 16px;
}
.footer-legal {
    max-width: var(--maxw);
    margin: 0 auto;
    padding: 0 1.5rem 2.4rem;
    font-size: 0.82rem;
}

/* Responsive */
@media (max-width: 900px) {
    .masthead-inner {
        flex-wrap: wrap;
    }
    .nav-toggle {
        display: inline-flex;
    }
    .nav-actions {
        margin-left: auto;
    }
    .nav-links {
        display: none;
        order: 3;
        width: 100%;
        margin-left: 0;
        flex-direction: column;
        gap: 0;
        padding: 0.3rem 0 0.1rem;
    }
    .masthead.nav-open .nav-links {
        display: flex;
    }
    .nav-links a {
        padding: 0.7rem 0.1rem;
        border-top: 1px solid var(--border);
        font-size: 1rem;
        box-shadow: none;
    }
}

@media (max-width: 640px) {
    body {
        font-size: 16px;
    }
    .wrap,
    .masthead-inner,
    .footer-inner,
    .footer-legal {
        padding-left: 1.1rem;
        padding-right: 1.1rem;
    }
    .section {
        padding: 2rem 0;
    }
    .page-title {
        font-size: 1.7rem;
    }
    .hero-inner {
        padding-top: 2.6rem;
        padding-bottom: 2.4rem;
    }
    .facts {
        gap: 1.5rem;
    }
    .person-header {
        grid-template-columns: 1fr;
        gap: 1.1rem;
    }
    .person-photo {
        width: 116px;
        height: 116px;
    }
    .news-item {
        grid-template-columns: 1fr;
        gap: 0.2rem;
    }
    .event {
        grid-template-columns: 60px 1fr;
        gap: 0.9rem;
    }
}