:root {
    --black: #2E2D29;
    --gray-dark: #43423E;
    --gray-medium: #DBDCDE;
    --gray-light: #F4F4F4;
    --gray-well: #EDECE8;
    --white: #FFFFFF;
    --cardinal: #8C1515;
    --cardinal-dark: #6E1010;

    --font-sans: 'Source Sans 3', 'Helvetica Neue', Helvetica, Arial, sans-serif;
    --font-serif: Georgia, 'Times New Roman', serif;

    --shadow: 0 0.25rem 1.25rem rgba(46, 45, 41, .12);
    --radius: 6px;
}

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

body {
    font-family: var(--font-sans);
    color: var(--black);
    font-size: 18.5px;
    line-height: 1.6;
    background: var(--white);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

a {
    color: var(--cardinal);
    text-decoration: underline;
    text-decoration-color: rgba(140, 21, 21, .4);
    transition: color .15s ease, text-decoration-color .15s ease
}

a:hover {
    color: var(--cardinal-dark);
    text-decoration-color: var(--cardinal-dark)
}

@media (prefers-reduced-motion: reduce) {
    * {
        transition-duration: .01ms !important;
        scroll-behavior: auto !important
    }
}

/* ===== Top Navigation — solid cardinal band ===== */
.navbar {
    position: sticky;
    top: 0;
    z-index: 30;
    background: var(--cardinal);
    color: var(--white);
    padding: 1.1rem 1.6rem;
    display: grid;
    grid-template-columns: 1fr auto 1fr;
    align-items: center;
    box-shadow: 0 2px 10px rgba(0, 0, 0, .15);
}

.brand {
    font-family: var(--font-sans);
    font-weight: 700;
    font-size: 1.45rem;
    color: var(--white);
    justify-self: start
}

.nav-links {
    display: flex;
    gap: 2.2rem;
    justify-self: center
}

.nav-links a {
    color: rgba(255, 255, 255, .92);
    text-decoration: none;
    font-weight: 600;
    font-size: 1.16rem;
    position: relative;
    padding-bottom: 4px;
    transition: color .15s ease
}

.nav-links a:hover {
    color: var(--white)
}

.nav-links a::after {
    content: "";
    position: absolute;
    left: 0;
    right: 0;
    bottom: -4px;
    height: 2px;
    background: var(--white);
    transform: scaleX(0);
    transform-origin: center;
    transition: transform .2s ease
}

.nav-links a:hover::after,
.nav-links a:focus-visible::after {
    transform: scaleX(1)
}

.menu-toggle {
    display: none;
    align-items: center;
    gap: .5rem;
    background: transparent;
    border: 0;
    color: var(--white);
    font-weight: 600;
    font-size: 1rem;
    cursor: pointer;
    justify-self: end
}

.menu-icon,
.menu-icon::before,
.menu-icon::after {
    display: block;
    width: 22px;
    height: 2px;
    background: currentColor;
    content: ""
}

.menu-icon {
    position: relative
}

.menu-icon::before {
    position: absolute;
    top: -7px
}

.menu-icon::after {
    position: absolute;
    top: 7px
}

.site-menu {
    display: none;
    position: absolute;
    top: 100%;
    right: 1rem;
    background: var(--white);
    border-radius: var(--radius);
    width: 75vw;
    max-width: 300px;
    padding: .5rem;
    box-shadow: var(--shadow)
}

.site-menu.open {
    display: flex;
    flex-direction: column
}

.site-menu a {
    color: var(--black);
    font-weight: 600;
    font-size: 1rem;
    text-decoration: none;
    padding: .65rem .75rem;
    border-radius: var(--radius)
}

.site-menu a:hover {
    color: var(--white);
    background: var(--cardinal)
}

/* ===== Header ===== */
.site-header {
    max-width: 780px;
    margin: 2.4rem auto 2rem;
    padding: 0 2rem;
    display: flex;
    flex-direction: column;
    align-items: center;
}

.header-top {
    display: flex;
    flex-direction: row;
    align-items: center;
    justify-content: center;
    text-align: left;
    gap: 2rem;
    width: 100%;
}

.header-photo img {
    width: 148px;
    height: 148px;
    border-radius: 50%;
    object-fit: cover;
    border: 4px solid var(--white);
    box-shadow: 0 0 0 3px var(--cardinal);
}

.header-text {
    display: flex;
    flex-direction: column;
    gap: .4rem;
}

.role-kicker {
    display: inline-block;
    background: var(--cardinal);
    color: var(--white);
    font-size: .8rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: .5px;
    padding: .3rem .7rem;
    border-radius: 999px;
    width: fit-content;
}

.header-email {
    display: flex;
    align-items: center;
    gap: .4rem;
    margin-top: .3rem;
    font-size: 1.08rem;
}

.mail-icon {
    color: var(--gray-dark);
    flex-shrink: 0;
}

.header-email a {
    color: var(--gray-dark);
    font-weight: 600;
    text-decoration-color: var(--gray-medium);
}

.header-email a:hover {
    color: var(--cardinal);
}

.header-email:hover .mail-icon {
    color: var(--cardinal);
}

.site-header h1 {
    margin: 0;
    font-size: clamp(1.9rem, 3.2vw, 2.4rem);
    font-family: var(--font-sans);
    font-weight: 700;
    color: var(--black);
}

.tagline {
    position: relative;
    max-width: 560px;
    margin: 0 auto 1.7rem;
    padding: 0 0 22px;
    text-align: center;
    font-family: var(--font-serif);
    line-height: 1.35;
}

.tagline::before,
.tagline::after {
    content: "";
    position: absolute;
    left: 0;
    right: 0;
    height: 1px;
    background: rgba(255, 255, 255, .3)
}

.tagline::before {
    display: none
}

.tagline::after {
    bottom: 0
}

.tagline p {
    margin: .35rem 0
}

.tagline .en {
    font-size: 1.15rem;
    font-style: italic;
    color: var(--white)
}

.tagline .cn {
    font-size: 1.02rem;
    font-style: italic;
    color: rgba(255, 255, 255, .78)
}

.tagline .quote-left,
.tagline .quote-right {
    font-size: 1.3rem;
    color: rgba(255, 255, 255, .85);
    vertical-align: middle;
    line-height: 1
}

.tagline .quote-left {
    margin-right: .3rem
}

.tagline .quote-right {
    margin-left: .3rem
}

/* ===== Main ===== */
main {
    max-width: 1180px;
    margin: 0 auto 2rem;
    padding: 0 2rem;
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 2.6rem
}

article h2,
aside h3 {
    font-family: var(--font-sans);
    font-weight: 700;
    color: var(--black)
}

article h2 {
    font-size: 2.05rem;
    margin: 2rem 0 1rem;
    padding-bottom: .6rem;
    border-bottom: 3px solid var(--cardinal);
}

article h2:first-of-type {
    margin-top: 0
}

.intro {
    margin-bottom: 1.1rem;
    color: var(--black);
    font-size: 1.12rem;
}

figure {
    margin: 1.7rem 0;
}

figure img {
    max-width: 65%;
    margin: 0 auto;
    display: block;
    height: auto;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
}

figcaption {
    font-size: .92rem;
    color: var(--gray-dark);
    margin-top: .55rem;
    text-align: center
}


.pub-list {
    margin-top: 1.2rem
}

.pub-item {
    background: var(--white);
    padding: 1.05rem 1.3rem;
    margin-bottom: .8rem;
    border-radius: var(--radius);
    border-left: 5px solid var(--cardinal);
    box-shadow: var(--shadow);
    line-height: 1.4;
}

.pub-item strong {
    color: var(--black);
    font-size: 1.25rem;
    font-weight: 700;
}

.pub-item small {
    color: var(--gray-dark);
    font-size: 1.05rem;
}

.pub-label {
    display: inline-block;
    background: var(--cardinal);
    color: var(--white);
    font-size: .78rem;
    font-weight: 700;
    line-height: 1.3;
    text-transform: uppercase;
    letter-spacing: .4px;
    padding: .25rem .7rem;
    margin-right: .5rem;
    vertical-align: middle;
    border-radius: 8px;
}

.pub-item a {
    display: inline-block;
    margin-top: .5rem;
    margin-right: .6rem;
    background: var(--cardinal);
    color: var(--white);
    font-size: .92rem;
    font-weight: 700;
    line-height: 1;
    text-decoration: none;
    padding: .45rem 1.15rem;
    border-radius: 999px;
    transition: background .15s ease, transform .15s ease;
}

.pub-item a:hover {
    background: var(--cardinal-dark);
    transform: translateY(-1px);
}

/* ===== Talks ===== */
.talks-timeline {
    position: relative;
    margin: 1.4rem 0;
    padding-left: 1.6rem;
    border-left: 3px solid var(--cardinal);
}

.talks-item {
    position: relative;
    margin-bottom: 1.7rem;
    padding-left: .2rem;
}

.talks-item:last-child {
    margin-bottom: 0;
}

.talks-item::before {
    content: "";
    position: absolute;
    left: calc(-1.6rem - 1.5px);
    top: .45rem;
    width: 12px;
    height: 12px;
    background: var(--cardinal);
    border-radius: 50%;
    border: 2px solid var(--white);
    transform: translateX(-50%);
}

.talk-year {
    display: block;
    font-size: .84rem;
    color: var(--cardinal);
    font-weight: 700;
    letter-spacing: .3px;
    margin-bottom: .3rem;
}

.talks-item strong {
    display: block;
    font-family: var(--font-sans);
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--black);
    margin-bottom: .35rem
}

.talks-item p {
    font-size: .98rem;
    color: var(--gray-dark)
}

.talk-loc {
    color: var(--cardinal);
    font-weight: 600;
}

/* ===== Aside ===== */
aside h3 {
    margin-top: 1.3rem;
    font-size: 1.55rem;
    padding-bottom: .5rem;
    border-bottom: 3px solid var(--cardinal);
}

aside h3:first-child {
    margin-top: 0
}

.research-tags {
    display: flex;
    flex-wrap: wrap;
    gap: .5rem;
    margin-top: .8rem;
    margin-bottom: .8rem
}

.tag {
    padding: .3rem 1rem;
    background: var(--cardinal);
    color: var(--white);
    border-radius: 8px;
    font-size: .98rem;
    font-weight: 600;
    line-height: 1.3;
    transition: background .15s ease
}

.tag:hover {
    background: var(--cardinal-dark);
}

.research-photo {
    margin-top: .9rem
}

.research-photo img {
    width: min(80%, 400px);
    display: block;
    border-radius: var(--radius);
}

/* News */
.accordion {
    margin-top: 1.1rem
}

.accordion-item {
    margin-bottom: .6rem;
    border-radius: var(--radius);
    overflow: hidden;
    box-shadow: var(--shadow);
}

.accordion-header {
    width: 100%;
    text-align: left;
    background: var(--cardinal);
    color: var(--white);
    padding: .8rem 1.05rem;
    border: none;
    font-size: 1rem;
    font-weight: 700;
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    transition: background .15s ease;
}

.accordion-header:hover {
    background: var(--cardinal-dark);
}

.accordion-header .arrow {
    color: var(--white);
    transition: transform .2s ease
}

.accordion-item.active .accordion-header .arrow {
    transform: rotate(90deg)
}

.accordion-content {
    display: none;
    background: var(--gray-light);
    padding: .95rem 1.05rem;
}

.accordion-content .news-item {
    padding: .55rem 0;
    border-bottom: 1px solid var(--gray-medium);
}

.accordion-content .news-item:last-child {
    border-bottom: none;
    padding-bottom: 0;
}

.accordion-content .news-item time {
    font-size: .84rem;
    color: var(--cardinal);
    font-weight: 700;
    text-transform: uppercase;
}

.accordion-content .news-item h4 {
    color: var(--black);
    margin: .25rem 0;
    font-size: 1.05rem;
    font-weight: 700;
}

.accordion-content .news-item p {
    color: var(--gray-dark);
    font-size: .96rem
}

.accordion-content .news-item img {
    max-width: 100%;
    height: auto;
    display: block;
    border-radius: var(--radius);
    margin: .35rem 0;
}

.accordion-item.active .accordion-content {
    display: block
}

/* Education */
.education-timeline {
    position: relative;
    margin: 1.5rem 0;
    padding-left: 1.4rem;
    border-left: 3px solid var(--cardinal)
}

.education-item {
    position: relative;
    margin-bottom: 1.1rem;
    padding-left: 1rem
}

.education-item:last-child {
    margin-bottom: 0;
}

.education-item::before {
    content: "";
    position: absolute;
    left: calc(-1.4rem - 1.5px);
    top: .5rem;
    width: 12px;
    height: 12px;
    background: var(--cardinal);
    border-radius: 50%;
    border: 2px solid var(--white);
    transform: translateX(-50%);
}

.education-item h4 {
    margin: 0 0 .22rem;
    color: var(--black);
    font-size: 1.08rem;
    font-weight: 700;
}

.education-item .year {
    font-size: .88rem;
    color: var(--cardinal);
    font-weight: 700;
    margin-bottom: .3rem;
    display: block
}

.education-item p {
    color: var(--gray-dark)
}

/* Academic Services */
.service-quote {
    font-family: var(--font-serif);
    font-style: italic;
    color: var(--gray-dark);
    margin-top: .45rem;
    font-size: 1rem
}

ul {
    list-style-position: inside;
    padding-left: 0;
    margin-left: 0;
}

ul li {
    color: var(--black);
    margin-bottom: .45rem;
    font-size: 1.02rem;
}

/* Contact */
#contact ul li {
    margin-bottom: .5rem;
    color: var(--black)
}

#contact a {
    color: var(--cardinal);
    font-weight: 700
}

/* Footer — solid cardinal band */
footer {
    background: var(--cardinal);
    color: var(--white);
    text-align: center;
    padding: 2rem 1rem;
    margin-top: 2.4rem;
}

.footer-top {
    margin-bottom: 1rem
}

.footer-top strong {
    font-weight: 700;
    font-size: 1.05rem;
}

.footer-top a {
    color: var(--white);
    margin: 0 .6rem;
    text-decoration: none;
    font-weight: 700;
}

.footer-top a:hover {
    text-decoration: underline;
    text-decoration-color: rgba(255, 255, 255, .7);
}

.footer-bottom {
    font-size: 1rem;
    color: rgba(255, 255, 255, .85)
}

/* ===== Responsive ===== */
@media (max-width:900px) {
    main {
        grid-template-columns: 1fr
    }

    figure img {
        max-width: 100%
    }

    .nav-links {
        display: none
    }

    .menu-toggle {
        display: flex
    }

    .navbar {
        grid-template-columns: auto 1fr auto
    }

    .site-header {
        margin: 1.8rem auto 1.8rem;
    }

    .header-top {
        flex-direction: column;
        text-align: center;
        justify-content: center;
        gap: .9rem;
    }

    .header-photo img {
        width: 100px;
        height: 100px
    }

    .tagline {
        max-width: 480px
    }

    .research-photo img {
        margin: 0 auto
    }
}

@media (max-width:480px) {
    .talks-timeline {
        padding-left: 1.3rem;
    }
}