/* ===== Reset & Base ===== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: "Helvetica Neue", Helvetica, Arial, "Microsoft YaHei", "PingFang SC", sans-serif;
    font-size: 15px;
    line-height: 1.8;
    color: #333;
    background: #fff;
}

a {
    color: #660874;
    text-decoration: none;
    transition: color 0.2s;
}

a:hover {
    color: #9b2fa8;
}

img {
    max-width: 100%;
    height: auto;
}

.container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 20px;
}

/* ===== Header ===== */
.site-header {
    background: linear-gradient(135deg, #4a0756 0%, #660874 50%, #7a0a8a 100%);
    color: #fff;
    padding: 28px 0 20px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.15);
}

.site-header .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
}

.site-logo {
    display: flex;
    align-items: center;
    gap: 15px;
}

.site-logo .logo-icon {
    width: 52px;
    height: 52px;
    background: rgba(255,255,255,0.15);
    border: 2px solid rgba(255,255,255,0.3);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 22px;
    font-weight: bold;
    color: #fff;
}

.site-logo-text h1 {
    font-size: 22px;
    font-weight: 600;
    margin: 0;
    letter-spacing: 0.5px;
}

.site-logo-text .university {
    font-size: 15px;
    opacity: 0.85;
    margin-top: 2px;
}

/* 副标题机构链接：固定淡色显示，悬停不变色，链接目标不变 */
.site-logo-text .university a {
    color: #fff;
}

.site-logo-text .university a:hover {
    color: #fff;
}

/* ===== Navigation ===== */
.nav-menu {
    display: flex;
    gap: 5px;
    list-style: none;
    flex-wrap: wrap;
}

.nav-menu li a {
    color: rgba(255,255,255,0.9);
    padding: 8px 16px;
    border-radius: 4px;
    font-size: 14px;
    transition: all 0.2s;
    display: block;
}

.nav-menu li a:hover,
.nav-menu li a.active {
    background: rgba(255,255,255,0.15);
    color: #fff;
}

/* Mobile nav toggle */
.nav-toggle {
    display: none;
    background: none;
    border: none;
    color: #fff;
    font-size: 24px;
    cursor: pointer;
    padding: 5px 10px;
}

/* ===== Main Content ===== */
.main-content {
    min-height: calc(100vh - 200px);
    padding: 40px 0 60px;
}

/* ===== Sections ===== */
.section {
    margin-bottom: 50px;
}

.section-title {
    font-size: 24px;
    font-weight: 600;
    color: #4a0756;
    border-bottom: 2px solid #e0d0e6;
    padding-bottom: 10px;
    margin-bottom: 25px;
}

.section-title .en {
    font-size: 14px;
    color: #999;
    font-weight: normal;
    margin-left: 10px;
}

/* ===== Intro Page ===== */
.intro-block {
    display: flex;
    gap: 40px;
    align-items: flex-start;
    flex-wrap: wrap;
}

.intro-text {
    flex: 1;
    min-width: 300px;
}

.intro-text p {
    margin-bottom: 16px;
    text-align: justify;
}

.intro-sidebar {
    width: 280px;
    flex-shrink: 0;
}

.info-card {
    background: #f8f5fa;
    border-left: 3px solid #660874;
    padding: 18px 20px;
    margin-bottom: 20px;
    border-radius: 0 4px 4px 0;
}

.info-card h3 {
    font-size: 15px;
    color: #4a0756;
    margin-bottom: 10px;
}

.info-card p {
    font-size: 14px;
    line-height: 1.7;
    color: #555;
}

/* ===== News List ===== */
.news-list {
    list-style: none;
}

.news-item {
    padding: 14px 0;
    border-bottom: 1px solid #eee;
    display: flex;
    gap: 15px;
    align-items: flex-start;
}

.news-date {
    color: #660874;
    font-weight: 600;
    font-size: 14px;
    white-space: nowrap;
    min-width: 90px;
}

.news-content {
    flex: 1;
}

.news-content .news-tag {
    display: inline-block;
    background: #f0e8f4;
    color: #660874;
    font-size: 12px;
    padding: 1px 8px;
    border-radius: 3px;
    margin-right: 6px;
}

/* ===== Research Areas ===== */
.research-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 25px;
}

.research-card {
    background: #fff;
    border: 1px solid #e8e8e8;
    border-radius: 8px;
    overflow: hidden;
    transition: box-shadow 0.3s;
}

.research-card:hover {
    box-shadow: 0 4px 20px rgba(102,8,116,0.1);
}

.research-card-header {
    background: linear-gradient(135deg, #660874, #7a0a8a);
    color: #fff;
    padding: 18px 22px;
}

.research-card-header h3 {
    font-size: 17px;
    margin: 0;
}

.research-card-body {
    padding: 18px 22px;
}

.research-card-body p {
    font-size: 14px;
    color: #555;
    line-height: 1.7;
}

.research-card-body .keywords {
    margin-top: 10px;
}

.research-card-body .keywords span {
    display: inline-block;
    background: #f0e8f4;
    color: #660874;
    font-size: 12px;
    padding: 2px 10px;
    border-radius: 3px;
    margin-right: 5px;
    margin-bottom: 5px;
}

/* ===== Publications ===== */
.pub-filter {
    margin-bottom: 25px;
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
}

.pub-filter button {
    background: #f5f5f5;
    border: 1px solid #ddd;
    color: #555;
    padding: 6px 16px;
    border-radius: 4px;
    cursor: pointer;
    font-size: 14px;
    transition: all 0.2s;
}

.pub-filter button:hover,
.pub-filter button.active {
    background: #660874;
    color: #fff;
    border-color: #660874;
}

.pub-list {
    list-style: none;
}

.pub-item {
    padding: 16px 0;
    border-bottom: 1px solid #eee;
}

.pub-item .pub-title {
    font-weight: 600;
    color: #333;
    font-size: 15px;
}

.pub-item .pub-authors {
    color: #666;
    font-size: 14px;
    margin-top: 3px;
}

.pub-item .pub-venue {
    color: #660874;
    font-size: 14px;
    font-style: italic;
    margin-top: 2px;
}

.pub-item .pub-links {
    margin-top: 6px;
}

.pub-item .pub-links a {
    font-size: 13px;
    margin-right: 12px;
}

/* ===== People ===== */
.people-section {
    margin-bottom: 40px;
}

.people-section h3 {
    font-size: 18px;
    color: #4a0756;
    margin-bottom: 20px;
    padding-bottom: 8px;
    border-bottom: 1px solid #e0d0e6;
}

.people-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 25px;
}

.person-card {
    text-align: center;
}

.person-avatar {
    width: 150px;
    height: 150px;
    border-radius: 50%;
    object-fit: cover;
    border: 3px solid #f0e8f4;
    margin-bottom: 12px;
    transition: border-color 0.3s;
}

.person-card:hover .person-avatar {
    border-color: #660874;
}

.person-name {
    font-size: 16px;
    font-weight: 600;
    color: #333;
}

.person-role {
    font-size: 13px;
    color: #888;
    margin-top: 3px;
}

.person-email {
    font-size: 13px;
    color: #660874;
    margin-top: 5px;
    word-break: break-all;
}

/* ===== Projects ===== */
.project-list {
    list-style: none;
}

.project-item {
    padding: 18px 22px;
    background: #f8f5fa;
    border-radius: 6px;
    margin-bottom: 12px;
    border-left: 3px solid #660874;
}

.project-item h4 {
    font-size: 15px;
    color: #333;
    margin-bottom: 5px;
}

.project-item .project-meta {
    font-size: 13px;
    color: #888;
}

.project-item .project-desc {
    font-size: 14px;
    color: #555;
    margin-top: 6px;
}

/* ===== Contact ===== */
.contact-block {
    display: flex;
    gap: 40px;
    flex-wrap: wrap;
}

.contact-info {
    flex: 1;
    min-width: 300px;
}

.contact-info dl {
    margin-top: 15px;
}

.contact-info dt {
    font-weight: 600;
    color: #4a0756;
    margin-top: 14px;
    font-size: 14px;
}

.contact-info dd {
    font-size: 14px;
    color: #555;
    margin-left: 0;
    margin-top: 3px;
}

.contact-map {
    flex: 1;
    min-width: 300px;
}

.contact-map iframe {
    width: 100%;
    height: 350px;
    border: 0;
    border-radius: 8px;
}

/* ===== Footer ===== */
.site-footer {
    background: #2d0435;
    color: rgba(255,255,255,0.7);
    padding: 30px 0 20px;
    font-size: 13px;
}

.site-footer .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 10px;
}

.footer-links a {
    color: rgba(255,255,255,0.6);
    margin-right: 15px;
}

.footer-links a:hover {
    color: #fff;
}

/* ===== Language Switch ===== */
.nav-menu li.lang-item a {
    border: 1px solid rgba(255,255,255,0.5);
    padding: 5px 14px;
    margin-left: 10px;
    font-weight: 600;
}

.nav-menu li.lang-item a:hover {
    background: rgba(255,255,255,0.2);
    color: #fff;
}

/* ===== Responsive ===== */
@media (max-width: 768px) {
    .nav-toggle {
        display: block;
    }

    .nav-menu {
        display: none;
        width: 100%;
        flex-direction: column;
        margin-top: 15px;
    }

    .nav-menu.open {
        display: flex;
    }

    .nav-menu li a {
        padding: 10px 16px;
    }

    .site-header .container {
        flex-direction: column;
        align-items: flex-start;
    }

    .site-logo {
        width: 100%;
        justify-content: space-between;
    }

    .intro-block {
        flex-direction: column;
    }

    .intro-sidebar {
        width: 100%;
    }

    .contact-block {
        flex-direction: column;
    }
}