:root {
    --primary-color: #172033;
    --secondary-color: #5d6676;
    --accent-color: #1f5fbf;
    --text-color: #232b3a;
    --bg-color: #f5f7fa;
    --subtle-bg: #eef2f7;
    --white: #ffffff;
    --border-color: #dfe4ea;
    --hover-color: #174ea6;
    --surface-shadow: 0 8px 24px rgba(23, 32, 51, 0.06);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Helvetica', 'Arial',
                 'Noto Sans JP', sans-serif;
    line-height: 1.65;
    color: var(--text-color);
    background-color: var(--bg-color);
    -webkit-font-smoothing: antialiased;
}

.container {
    width: min(100%, 1280px);
    margin: 0 auto;
    padding: 0 clamp(18px, 3vw, 32px);
}

.site-header {
    border-bottom: 1px solid var(--border-color);
    padding: 0.9rem 0;
    background-color: rgba(255, 255, 255, 0.96);
}

.header-top {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    gap: 1rem;
}

.header-actions {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    flex-wrap: wrap;
}

.nav-actions {
    justify-content: flex-start;
}

.language-actions {
    justify-content: flex-end;
    margin-left: auto;
}

.header-link,
#language-toggle {
    background-color: var(--white);
    color: var(--text-color);
    border: 1px solid var(--border-color);
    padding: 0.42rem 0.85rem;
    border-radius: 999px;
    cursor: pointer;
    font-size: 0.9rem;
    font-weight: 600;
    transition: background-color 0.2s ease, border-color 0.2s ease, color 0.2s ease;
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    justify-content: center;
}

.header-link:hover,
#language-toggle:hover {
    background-color: var(--subtle-bg);
    border-color: #bdbdbd;
}

.header-link:focus-visible,
#language-toggle:focus-visible,
.sidebar-link-button:focus-visible {
    outline: 2px solid var(--hover-color);
    outline-offset: 2px;
}

.toggle-label {
    display: none;
}

body[data-lang="en"] .toggle-label[data-lang="en"],
body[data-lang="ja"] .toggle-label[data-lang="ja"] {
    display: inline;
}

body[data-lang="en"] [lang="ja"] {
    display: none !important;
}

body[data-lang="ja"] [lang="en"] {
    display: none !important;
}

body[data-lang="en"] .talk-event-native[lang="ja"] {
    display: block !important;
}

.page-layout {
    display: grid;
    grid-template-columns: clamp(230px, 21vw, 300px) minmax(0, 1fr);
    gap: clamp(1.25rem, 2.5vw, 2.25rem);
    align-items: start;
    padding-top: 2rem;
    padding-bottom: 3rem;
}

.content-page {
    padding-top: 2rem;
    padding-bottom: 3rem;
}

.sidebar {
    position: sticky;
    top: 20px;
    border: 1px solid var(--border-color);
    border-radius: 16px;
    overflow: hidden;
    background-color: var(--white);
    box-shadow: var(--surface-shadow);
}

.sidebar-inner {
    padding: clamp(1rem, 1.8vw, 1.35rem);
}

.sidebar-image {
    width: 100%;
    max-width: 100%;
    margin-bottom: 1rem;
}

.sidebar-image img {
    display: block;
    width: 100%;
    aspect-ratio: 16 / 10;
    object-fit: cover;
    object-position: center 12%;
    border-radius: 12px;
    border: 1px solid var(--border-color);
}

.sidebar-text h1 {
    font-size: clamp(1.5rem, 2vw, 1.8rem);
    line-height: 1.2;
    margin-bottom: 0.65rem;
}

.sidebar-text h1 span {
    display: block;
    font-size: 1em;
    color: var(--primary-color);
    margin-top: 0;
}

.sidebar-links {
    margin-top: 1rem;
    padding-top: 1rem;
    border-top: 1px solid var(--border-color);
}

.sidebar-links h2 {
    font-size: 0.95rem;
    font-weight: 700;
    letter-spacing: 0.04em;
    margin-bottom: 0.85rem;
    color: var(--secondary-color);
}

.lead {
    font-size: 0.92rem;
    line-height: 1.55;
    color: var(--secondary-color);
    margin-bottom: 0.35rem;
}

.main-content {
    min-width: 0;
}

.content-section-inner {
    padding: 0;
}

main {
    padding: 0;
}

.section {
    padding: clamp(1.25rem, 2vw, 1.75rem);
    background-color: var(--white);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    box-shadow: 0 2px 10px rgba(23, 32, 51, 0.035);
}

.section.alt {
    background-color: var(--white);
}

.sidebar.section {
    padding: 0;
    box-shadow: var(--surface-shadow);
}

.section + .section {
    margin-top: 1rem;
}

.section h2 {
    font-size: clamp(1.28rem, 1.6vw, 1.5rem);
    line-height: 1.25;
    letter-spacing: -0.015em;
    margin-bottom: 1rem;
    padding-bottom: 0.65rem;
    border-bottom: 1px solid var(--border-color);
}

.section p,
.section li {
    font-size: 1rem;
}

.sidebar .lead {
    font-size: 0.92rem;
}

.content-section-inner > p {
    max-width: 75ch;
}

.profile-list,
.career-list,
.links-list,
.publications-list {
    padding-left: 1.25rem;
}

.profile-list {
    margin-top: 0.75rem;
}

.profile-list li,
.career-list li,
.links-list li,
.publications-list li {
    margin-bottom: 0.55rem;
}

.profile-list li::marker,
.career-list li::marker,
.publications-list li::marker {
    color: var(--accent-color);
}

.sidebar-links-list {
    list-style: none;
    padding-left: 0;
    display: flex;
    flex-wrap: nowrap;
    justify-content: center;
    gap: 0.35rem;
}

.sidebar-links-list li {
    margin-bottom: 0;
}

.sidebar-link-button {
    display: flex;
    align-items: center;
    justify-content: center;
    width: auto;
    min-height: 2rem;
    padding: 0.3rem 0.4rem;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    background-color: var(--white);
    color: var(--text-color);
    text-decoration: none;
    font-size: 0.68rem;
    line-height: 1.15;
    letter-spacing: -0.01em;
    white-space: nowrap;
    font-weight: 600;
    transition: transform 0.15s ease, background-color 0.2s ease, border-color 0.2s ease, box-shadow 0.2s ease;
    box-shadow: 0 1px 2px rgba(17, 17, 17, 0.04);
}

.sidebar-link-button:hover {
    transform: translateY(-1px);
    background-color: var(--white);
    border-color: #bdbdbd;
    color: var(--text-color);
    box-shadow: 0 4px 12px rgba(17, 17, 17, 0.08);
}

.sidebar-link-icon {
    display: none;
}

.organization-grid,
.preprints-grid,
.published-grid,
.talks-grid {
    display: grid;
    gap: 0.8rem;
}

.organization-card,
.preprint-card,
.published-card,
.talk-card {
    border: 1px solid var(--border-color);
    border-radius: 12px;
    background-color: #fbfcfe;
    padding: 1rem 1.1rem;
    box-shadow: none;
}

.organization-card-link {
    color: inherit;
    text-decoration: none;
    transition: background-color 0.2s ease, border-color 0.2s ease, box-shadow 0.2s ease;
}

.organization-card-link:hover {
    color: inherit;
    background-color: var(--white);
    border-color: #bcc8d8;
    box-shadow: 0 6px 18px rgba(23, 32, 51, 0.07);
}

.organization-title {
    font-size: 1rem;
    line-height: 1.5;
    margin-bottom: 0.5rem;
}

.organization-meta {
    color: var(--secondary-color);
    font-size: 0.92em;
}

.organization-meta strong {
    font-size: 0.95em;
}

.preprint-card::before {
    content: "#" attr(data-order);
    display: inline-flex;
    align-items: center;
    border-radius: 999px;
    padding: 0.12rem 0.55rem;
    margin-top: 0.1rem;
    background-color: #edf3ff;
    border: 1px solid #cddcff;
    color: var(--accent-color);
    font-size: 0.82rem;
    font-weight: 600;
    line-height: 1.3;
    grid-column: 1;
    grid-row: 1;
}

.preprint-card {
    display: grid;
    grid-template-columns: auto minmax(0, 1fr);
    column-gap: 0.65rem;
    align-items: start;
}

.preprint-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    gap: 0.8rem;
    grid-column: 2;
    grid-row: 1;
    min-width: 0;
}

.preprint-title {
    font-size: 1rem;
    line-height: 1.5;
}

.preprint-year {
    border: 1px solid var(--border-color);
    border-radius: 999px;
    padding: 0.12rem 0.55rem;
    font-size: 0.85rem;
    color: var(--secondary-color);
    line-height: 1.3;
    white-space: nowrap;
}

.preprint-authors {
    margin-top: 0.65rem;
    color: var(--secondary-color);
    grid-column: 1 / -1;
}

.preprint-links {
    margin-top: 0.75rem;
    grid-column: 1 / -1;
}

.published-card {
    border-color: #c8d0de;
    background: linear-gradient(180deg, #fbfcff 0%, #ffffff 100%);
    padding: 1.15rem 1.2rem;
    display: grid;
    grid-template-columns: auto minmax(0, 1fr);
    column-gap: 0.65rem;
    row-gap: 0.4rem;
    align-items: start;
}

.published-card::before {
    content: "#" attr(data-order);
    display: inline-flex;
    align-items: center;
    border-radius: 999px;
    padding: 0.12rem 0.55rem;
    background-color: #edf3ff;
    border: 1px solid #cddcff;
    color: var(--accent-color);
    font-size: 0.82rem;
    font-weight: 600;
    line-height: 1.3;
    width: fit-content;
    margin-top: 0.1rem;
    grid-column: 1;
    grid-row: 1;
}

.published-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    gap: 0.8rem;
    grid-column: 2;
    grid-row: 1;
    min-width: 0;
}

.published-title {
    font-size: 1rem;
    line-height: 1.5;
    margin: 0;
}

.published-year {
    border: 1px solid var(--border-color);
    border-radius: 999px;
    padding: 0.12rem 0.55rem;
    font-size: 0.85rem;
    color: var(--secondary-color);
    line-height: 1.3;
    white-space: nowrap;
}

.published-authors {
    margin: 0;
    color: var(--secondary-color);
    line-height: 1.45;
    grid-column: 1 / -1;
}

.published-venue {
    margin: 0;
    font-size: 0.95rem;
    font-weight: 600;
    color: var(--secondary-color);
    line-height: 1.35;
    grid-column: 1 / -1;
}

.published-links {
    margin-top: 0.05rem;
    display: flex;
    flex-wrap: wrap;
    gap: 0.45rem;
    grid-column: 1 / -1;
}

.talk-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    gap: 0.8rem;
}

.talk-title {
    font-size: 1rem;
    line-height: 1.5;
}

.talk-date {
    border: 1px solid var(--border-color);
    border-radius: 999px;
    padding: 0.12rem 0.55rem;
    font-size: 0.85rem;
    color: var(--secondary-color);
    line-height: 1.3;
    white-space: nowrap;
}

.talk-speakers {
    margin-top: 0.5rem;
    color: var(--secondary-color);
    font-size: 0.95em;
}

.talk-event {
    margin-top: 0.3rem;
    color: var(--secondary-color);
    font-size: 0.92em;
}

.section .organization-meta,
.section .preprint-authors,
.section .published-authors,
.section .published-venue,
.section .talk-speakers,
.section .talk-event,
.section .talk-location {
    font-size: 1rem;
    line-height: 1.5;
}

.organization-meta strong {
    font-size: inherit;
}

.badge-arxiv {
    display: inline-flex;
    align-items: center;
    border-radius: 999px;
    padding: 0.2rem 0.65rem;
    background-color: #edf3ff;
    border: 1px solid #cddcff;
    font-size: 0.88rem;
    font-weight: 600;
    text-decoration: none;
}

a {
    color: var(--accent-color);
}

a:hover {
    color: var(--hover-color);
}

.site-footer {
    border-top: 1px solid var(--border-color);
    padding: 1.5rem 0;
    color: var(--secondary-color);
    background-color: var(--white);
}

.page-hero h1 {
    font-size: clamp(2.2rem, 5vw, 3.2rem);
    line-height: 1.1;
}

@media (max-width: 900px) {
    .page-layout {
        grid-template-columns: 1fr;
        gap: 1.25rem;
        padding-top: 1.25rem;
    }

    .sidebar {
        position: static;
    }

    .sidebar-inner {
        display: grid;
        grid-template-columns: minmax(160px, 220px) minmax(0, 1fr);
        column-gap: 1.25rem;
        align-items: center;
    }

    .sidebar-image {
        max-width: 220px;
        margin-bottom: 0;
        grid-row: 1 / span 2;
    }

    .sidebar-links {
        grid-column: 2;
        margin-top: 0.75rem;
        padding-top: 0.75rem;
    }
}

@media (max-width: 768px) {
    .container {
        width: 100%;
        padding: 0 18px;
    }

    .container.content-page {
        padding-top: 1.25rem;
        padding-bottom: 2rem;
    }

    .header-top {
        flex-direction: column;
        align-items: stretch;
    }

    .language-actions {
        justify-content: flex-start;
        margin-left: 0;
    }

    .site-header {
        padding: 0.8rem 0;
    }

    .section {
        padding: 1.1rem;
    }

    .section + .section {
        margin-top: 0.5rem;
    }

    .content-section-inner {
        padding: 0;
    }
}

@media (max-width: 600px) {
    .preprint-card,
    .published-card {
        grid-template-columns: minmax(0, 1fr) auto;
        row-gap: 0.65rem;
        padding: 1rem;
    }

    .preprint-card::before,
    .published-card::before {
        grid-column: 1;
        grid-row: 1;
        margin-top: 0;
    }

    .preprint-header,
    .published-header {
        display: contents;
    }

    .preprint-title,
    .published-title {
        grid-column: 1 / -1;
        grid-row: 2;
    }

    .preprint-year,
    .published-year {
        grid-column: 2;
        grid-row: 1;
        justify-self: end;
    }

    .preprint-authors,
    .preprint-links,
    .published-links {
        margin-top: 0;
    }

    .sidebar-inner {
        display: block;
    }

    .sidebar-image {
        max-width: min(220px, 100%);
        margin: 0 auto 1rem;
    }

    .sidebar-text {
        text-align: center;
    }

    .sidebar-links {
        margin-top: 0.85rem;
    }
}

@media (max-width: 480px) {
    .sidebar-image {
        max-width: min(220px, 100%);
    }

    .sidebar-text h1 {
        font-size: 1.55rem;
    }

    .page-hero h1 {
        font-size: 2rem;
    }

    .section p,
    .section li,
    .header-link,
    #language-toggle {
        font-size: 0.95rem;
    }

    .talk-header {
        flex-direction: column-reverse;
        gap: 0.4rem;
    }

}