/* ============================================================
   孔学谦课题组 · 清新简洁主题
   ============================================================ */

:root {
  --ink: #17262e;
  --ink-2: #35505d;
  --muted: #6d8794;
  --line: #e2eaee;
  --line-soft: #eef3f5;
  --bg: #ffffff;
  --bg-soft: #f6f9fa;
  --bg-tint: #eef6f8;

  --accent: #2d7d9a;
  --accent-dark: #21617a;
  --accent-soft: #d9ecf2;
  --green: #4a7c59;
  --green-soft: #e2efe6;
  --amber: #c07a3c;
  --amber-soft: #f7ead9;

  --radius: 14px;
  --radius-sm: 9px;
  --shadow: 0 1px 2px rgba(23, 38, 46, .04), 0 8px 28px rgba(23, 38, 46, .06);
  --shadow-sm: 0 1px 3px rgba(23, 38, 46, .06);
  --maxw: 1120px;
  --font: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", "Source Han Sans SC", sans-serif;
  --font-serif: "Iowan Old Style", "Georgia", "Songti SC", "Source Han Serif SC", serif;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; scroll-padding-top: 74px; }

body {
  margin: 0;
  font-family: var(--font);
  color: var(--ink);
  background: var(--bg);
  font-size: 16px;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
}

img { max-width: 100%; display: block; }
a { color: var(--accent); text-decoration: none; transition: color .18s; }
a:hover { color: var(--accent-dark); }

.wrap { max-width: var(--maxw); margin: 0 auto; padding: 0 24px; }

/* ---------- 顶栏 ---------- */
.nav {
  position: sticky; top: 0; z-index: 50;
  background: rgba(255, 255, 255, .88);
  backdrop-filter: saturate(1.6) blur(12px);
  border-bottom: 1px solid var(--line);
}
.nav-in {
  max-width: var(--maxw); margin: 0 auto; padding: 0 24px;
  height: 66px; display: flex; align-items: center; gap: 28px;
}
.brand { display: flex; align-items: center; gap: 11px; flex-shrink: 0; }
.brand img { height: 32px; width: auto; }
.brand-txt strong { display: block; font-size: 15.5px; letter-spacing: .2px; color: var(--ink); line-height: 1.25; }
.brand-txt span { display: block; font-size: 10.5px; color: var(--muted); letter-spacing: 1.1px; text-transform: uppercase; }
.nav-links { display: flex; gap: 4px; margin-left: auto; flex-wrap: wrap; }
.nav-links a {
  color: var(--ink-2); font-size: 14.5px; padding: 7px 12px; border-radius: 8px;
  transition: background .18s, color .18s;
}
.nav-links a:hover { background: var(--bg-tint); color: var(--accent-dark); }
.nav-links a.active { color: var(--accent); background: var(--accent-soft); }
.nav-toggle {
  display: none; margin-left: auto; background: none; border: 1px solid var(--line);
  border-radius: 8px; width: 40px; height: 36px; cursor: pointer; color: var(--ink-2); font-size: 17px;
}

/* ---------- 通用区块 ---------- */
section { padding: 82px 0; }
section:nth-of-type(even) { background: var(--bg-soft); }
.sec-head { max-width: 760px; margin-bottom: 46px; }
.sec-kicker {
  font-size: 11.5px; letter-spacing: 2.2px; text-transform: uppercase;
  color: var(--accent); font-weight: 600; margin-bottom: 10px;
}
.sec-head h2 {
  font-size: 32px; line-height: 1.3; margin: 0 0 14px; font-weight: 650;
  letter-spacing: -.3px; color: var(--ink);
}
.sec-head p { margin: 0; color: var(--muted); font-size: 16.5px; }

/* ---------- Hero ---------- */
.hero { padding: 78px 0 68px; background:
  radial-gradient(1000px 420px at 12% -8%, #eaf5f8 0%, rgba(234,245,248,0) 62%),
  radial-gradient(760px 380px at 92% 4%, #f2f7ee 0%, rgba(242,247,238,0) 60%), #fff; }
.hero-grid { display: grid; grid-template-columns: 1.08fr .92fr; gap: 54px; align-items: center; }
.hero-badge {
  display: inline-block; font-size: 12.5px; color: var(--accent-dark);
  background: var(--accent-soft); border-radius: 999px; padding: 5px 14px;
  letter-spacing: .3px; margin-bottom: 20px;
}
.hero h1 { font-size: 44px; line-height: 1.18; margin: 0 0 8px; font-weight: 680; letter-spacing: -.8px; }
.hero .sub {
  font-family: var(--font-serif); font-size: 18px; color: var(--muted);
  letter-spacing: .6px; margin: 0 0 22px; font-style: italic;
}
.hero .lead { font-size: 18.5px; color: var(--ink-2); margin: 0 0 18px; line-height: 1.72; }
.hero .intro { color: var(--muted); margin: 0 0 30px; font-size: 15.5px; }
.hero-cta { display: flex; gap: 12px; flex-wrap: wrap; }
.btn {
  display: inline-flex; align-items: center; gap: 7px; border-radius: 10px;
  padding: 11px 22px; font-size: 15px; font-weight: 500; cursor: pointer;
  border: 1px solid transparent; transition: all .18s; font-family: inherit;
}
.btn-primary { background: var(--accent); color: #fff; }
.btn-primary:hover { background: var(--accent-dark); color: #fff; }
.btn-ghost { background: #fff; border-color: var(--line); color: var(--ink-2); }
.btn-ghost:hover { border-color: var(--accent); color: var(--accent); }
.hero-media { position: relative; }
.hero-media img { border-radius: var(--radius); box-shadow: var(--shadow); }
.hero-stats {
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 1px;
  background: var(--line); border: 1px solid var(--line);
  border-radius: var(--radius); overflow: hidden; margin-top: 46px;
}
.hero-stats div { background: #fff; padding: 20px 16px; text-align: center; }
.hero-stats b { display: block; font-size: 24px; color: var(--accent); font-weight: 650; letter-spacing: -.4px; }
.hero-stats span { font-size: 12.5px; color: var(--muted); }

/* ---------- About ---------- */
.about-grid { display: grid; grid-template-columns: 1.25fr .75fr; gap: 52px; align-items: start; }
.about-grid p { color: var(--ink-2); margin: 0 0 18px; }
.about-media img {
  border-radius: var(--radius); border: 1px solid var(--line);
  background: #fff; padding: 18px;
}

/* ---------- 研究方向 ---------- */
.rs-list { display: grid; gap: 22px; }
.rs-card {
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  overflow: hidden; box-shadow: var(--shadow-sm); transition: box-shadow .22s, transform .22s;
}
.rs-card:hover { box-shadow: var(--shadow); transform: translateY(-2px); }
.rs-inner { display: grid; grid-template-columns: 190px 1fr; gap: 0; }
.rs-thumb {
  background: var(--bg-tint); display: flex; align-items: center; justify-content: center;
  padding: 26px; border-right: 1px solid var(--line-soft);
}
.rs-thumb img { max-height: 130px; width: auto; object-fit: contain; }
.rs-body { padding: 28px 30px; }
.rs-tag {
  display: inline-block; font-size: 11.5px; letter-spacing: 1.4px; text-transform: uppercase;
  font-weight: 600; padding: 3px 10px; border-radius: 6px; margin-bottom: 11px;
}
.rs-body h3 { margin: 0 0 6px; font-size: 22px; font-weight: 640; letter-spacing: -.2px; }
.rs-body h3 small { font-weight: 400; font-size: 14px; color: var(--muted); margin-left: 9px; font-family: var(--font-serif); }
.rs-sum { color: var(--ink-2); font-size: 16px; margin: 0 0 12px; font-weight: 500; }
.rs-detail { color: var(--muted); font-size: 15px; margin: 0 0 16px; }
.rs-points { list-style: none; padding: 0; margin: 0; display: grid; gap: 9px; }
.rs-points li {
  position: relative; padding-left: 20px; font-size: 14.8px; color: var(--ink-2); line-height: 1.65;
}
.rs-points li::before {
  content: ""; position: absolute; left: 3px; top: 10px; width: 6px; height: 6px;
  border-radius: 50%; background: currentColor; opacity: .45;
}

/* ---------- 文献 ---------- */
.pub-bar {
  display: flex; gap: 12px; flex-wrap: wrap; align-items: center;
  margin-bottom: 24px; padding-bottom: 22px; border-bottom: 1px solid var(--line);
}
.pub-search {
  flex: 1 1 250px; min-width: 200px; border: 1px solid var(--line); border-radius: 10px;
  padding: 10px 14px; font-size: 14.5px; font-family: inherit; color: var(--ink);
  background: #fff; transition: border-color .18s;
}
.pub-search:focus { outline: none; border-color: var(--accent); }
.chips { display: flex; gap: 7px; flex-wrap: wrap; }
.chip {
  border: 1px solid var(--line); background: #fff; border-radius: 999px;
  padding: 6px 15px; font-size: 13.5px; cursor: pointer; color: var(--ink-2);
  font-family: inherit; transition: all .16s; white-space: nowrap;
}
.chip:hover { border-color: var(--accent); color: var(--accent); }
.chip.on { background: var(--accent); border-color: var(--accent); color: #fff; }
.pub-meta-bar { font-size: 13.5px; color: var(--muted); display: flex; gap: 16px; flex-wrap: wrap; align-items: center; }
.sync-dot { display: inline-block; width: 7px; height: 7px; border-radius: 50%; background: var(--green); margin-right: 5px; }

.pub-year-group { margin-bottom: 34px; }
.pub-year-label {
  font-size: 13px; font-weight: 650; color: var(--accent); letter-spacing: 1.6px;
  padding-bottom: 8px; margin-bottom: 16px; border-bottom: 1px solid var(--line-soft);
}
.pub {
  display: grid; grid-template-columns: 1fr auto; gap: 18px;
  padding: 20px 22px; border: 1px solid var(--line); border-radius: var(--radius);
  background: #fff; margin-bottom: 12px; transition: border-color .18s, box-shadow .18s;
}
.pub:hover { border-color: #c9dde5; box-shadow: var(--shadow-sm); }
.pub.is-featured { border-left: 3px solid var(--accent); }
.pub h4 { margin: 0 0 7px; font-size: 16.5px; line-height: 1.5; font-weight: 600; color: var(--ink); }
.pub h4 a { color: inherit; }
.pub h4 a:hover { color: var(--accent); }
.pub .authors { font-size: 13.5px; color: var(--muted); margin: 0 0 5px; }
.pub .venue { font-size: 13.5px; color: var(--ink-2); margin: 0 0 11px; }
.pub .venue em { font-style: normal; font-weight: 600; }
.pub .summary {
  font-size: 14.6px; color: var(--ink-2); background: var(--bg-tint);
  border-radius: var(--radius-sm); padding: 12px 15px; margin: 0; line-height: 1.72;
  border-left: 2px solid var(--accent-soft);
}
.pub .summary.draft { background: #fdf6e9; border-left-color: #f0d9ac; }
.pub-side { display: flex; flex-direction: column; align-items: flex-end; gap: 8px; min-width: 78px; }
.cite-box { text-align: center; }
.cite-box b { display: block; font-size: 19px; color: var(--accent); font-weight: 650; line-height: 1.2; }
.cite-box span { font-size: 11px; color: var(--muted); }
.topic-pills { display: flex; flex-direction: column; gap: 5px; align-items: flex-end; }
.pill { font-size: 11px; padding: 2px 8px; border-radius: 5px; white-space: nowrap; }
.badge-star { font-size: 11px; color: var(--amber); background: var(--amber-soft); padding: 2px 8px; border-radius: 5px; }
.pub-more { text-align: center; margin-top: 26px; }

/* ---------- PI / 团队 ---------- */
.pi-card {
  display: grid; grid-template-columns: 230px 1fr; gap: 38px;
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  padding: 34px; box-shadow: var(--shadow-sm); margin-bottom: 46px;
}
.pi-photo img { width: 100%; border-radius: var(--radius); box-shadow: var(--shadow-sm); object-fit: cover; }
.pi-photo .pi-mail {
  display: block; text-align: center; margin-top: 14px; font-size: 14px;
  background: var(--bg-tint); border-radius: 8px; padding: 8px;
}
.pi-info h3 { margin: 0 0 4px; font-size: 27px; font-weight: 650; letter-spacing: -.3px; }
.pi-info h3 small { font-family: var(--font-serif); font-weight: 400; font-size: 16px; color: var(--muted); margin-left: 10px; }
.pi-role { color: var(--accent); font-size: 15px; font-weight: 550; margin: 0 0 14px; }
.pi-aff { list-style: none; padding: 0; margin: 0 0 18px; font-size: 14.3px; color: var(--muted); }
.pi-aff li { padding: 1px 0; }
.pi-bio { color: var(--ink-2); font-size: 15.3px; margin: 0 0 22px; }
.pi-cols { display: grid; grid-template-columns: repeat(2, 1fr); gap: 22px 34px; }
.pi-block h5 {
  margin: 0 0 9px; font-size: 12px; letter-spacing: 1.6px; text-transform: uppercase;
  color: var(--accent); font-weight: 650;
}
.pi-block ul { list-style: none; padding: 0; margin: 0; font-size: 14.2px; color: var(--ink-2); }
.pi-block li { display: flex; gap: 11px; padding: 3px 0; line-height: 1.6; }
.pi-block li .k { color: var(--muted); flex-shrink: 0; min-width: 76px; font-variant-numeric: tabular-nums; font-size: 13.5px; }
.pi-note { margin-top: 18px; font-size: 14px; color: var(--muted); border-top: 1px dashed var(--line); padding-top: 14px; }

.team-group { margin-bottom: 34px; }
.team-group h4 {
  font-size: 13px; letter-spacing: 1.8px; text-transform: uppercase; color: var(--accent);
  margin: 0 0 18px; font-weight: 650;
}
.people { display: grid; grid-template-columns: repeat(auto-fill, minmax(148px, 1fr)); gap: 20px; }
.person { text-align: center; }
.person .ph {
  width: 100%; aspect-ratio: 1/1; border-radius: 50%; overflow: hidden;
  background: var(--bg-tint); margin-bottom: 11px; border: 1px solid var(--line-soft);
}
.person .ph img { width: 100%; height: 100%; object-fit: cover; }
.person b { display: block; font-size: 15px; font-weight: 600; }
.person span { display: block; font-size: 12.5px; color: var(--muted); }
.person em { display: block; font-size: 12px; color: var(--accent); font-style: normal; margin-top: 2px; }

.alumni-box {
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius); padding: 26px 30px;
}
.alumni-list { display: grid; grid-template-columns: repeat(auto-fill, minmax(216px, 1fr)); gap: 9px 22px; margin-top: 14px; }
.alumni-list div { font-size: 14.2px; color: var(--ink-2); display: flex; justify-content: space-between; gap: 10px; padding: 4px 0; border-bottom: 1px dashed var(--line-soft); }
.alumni-list em { font-style: normal; color: var(--muted); font-size: 13px; text-align: right; }

/* ---------- 平台 ---------- */
.fac-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(232px, 1fr)); gap: 20px; margin-bottom: 34px; }
.fac {
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  padding: 26px 24px; text-align: center; transition: transform .2s, box-shadow .2s;
}
.fac:hover { transform: translateY(-3px); box-shadow: var(--shadow); }
.fac .ic { height: 62px; display: flex; align-items: center; justify-content: center; margin-bottom: 15px; }
.fac .ic img { max-height: 58px; width: auto; }
.fac b { display: block; font-size: 16.5px; margin-bottom: 2px; font-weight: 620; }
.fac span { display: block; font-size: 12px; color: var(--muted); font-family: var(--font-serif); margin-bottom: 10px; letter-spacing: .3px; }
.fac p { margin: 0; font-size: 14.2px; color: var(--ink-2); line-height: 1.68; }
.cap-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(232px, 1fr)); gap: 1px; background: var(--line); border: 1px solid var(--line); border-radius: var(--radius); overflow: hidden; }
.cap-grid div { background: #fff; padding: 22px 24px; }
.cap-grid b { display: block; color: var(--accent); font-size: 15.5px; margin-bottom: 6px; }
.cap-grid p { margin: 0; font-size: 14.2px; color: var(--ink-2); }

/* ---------- 新闻 / 相册 ---------- */
.news-list { display: grid; gap: 2px; background: var(--line); border: 1px solid var(--line); border-radius: var(--radius); overflow: hidden; }
.news-item { background: #fff; padding: 18px 24px; display: grid; grid-template-columns: 92px 1fr; gap: 18px; align-items: baseline; }
.news-item time { font-size: 13px; color: var(--accent); font-variant-numeric: tabular-nums; font-weight: 600; }
.news-item b { display: block; font-size: 15.5px; font-weight: 600; margin-bottom: 2px; }
.news-item p { margin: 0; font-size: 14.2px; color: var(--muted); }

.gal { display: grid; grid-template-columns: repeat(auto-fit, minmax(248px, 1fr)); gap: 18px; }
.gal figure { margin: 0; border-radius: var(--radius); overflow: hidden; border: 1px solid var(--line); background: #fff; }
.gal img { width: 100%; height: 208px; object-fit: cover; transition: transform .45s ease; }
.gal figure:hover img { transform: scale(1.045); }
.gal figcaption { padding: 12px 16px; font-size: 13.8px; color: var(--ink-2); display: flex; justify-content: space-between; gap: 10px; }
.gal figcaption span { color: var(--muted); font-size: 12.5px; }

/* ---------- 加入 / 联系 ---------- */
.join-box { display: grid; grid-template-columns: 1fr 1fr; gap: 44px; align-items: start; }
.join-box > p { font-size: 16.5px; color: var(--ink-2); margin: 0; }
.join-notes { list-style: none; padding: 0; margin: 0; display: grid; gap: 13px; }
.join-notes li {
  background: #fff; border: 1px solid var(--line); border-left: 3px solid var(--green);
  border-radius: var(--radius-sm); padding: 14px 18px; font-size: 14.5px; color: var(--ink-2);
}
.contact-grid { display: grid; grid-template-columns: 1.4fr .6fr; gap: 44px; align-items: start; }
.contact-grid h3 { margin: 0 0 5px; font-size: 19px; font-weight: 620; }
.contact-grid .en { color: var(--muted); font-size: 14px; margin: 0 0 18px; font-family: var(--font-serif); }
.c-row { display: flex; gap: 13px; padding: 9px 0; border-bottom: 1px dashed var(--line); font-size: 15px; }
.c-row .k { color: var(--muted); min-width: 62px; flex-shrink: 0; }
.qr { text-align: center; }
.qr img { border-radius: var(--radius); border: 1px solid var(--line); }
.qr span { display: block; font-size: 13px; color: var(--muted); margin-top: 9px; }

/* ---------- 页脚 ---------- */
footer { background: #14252d; color: #a9c2cc; padding: 42px 0 32px; font-size: 14px; }
footer .f-in { display: flex; justify-content: space-between; gap: 22px; flex-wrap: wrap; align-items: center; }
footer a { color: #cfe3ea; }
footer a:hover { color: #fff; }
footer .f-links { display: flex; gap: 20px; flex-wrap: wrap; }

/* ---------- 载入 / 提示 ---------- */
.loading { text-align: center; padding: 60px 0; color: var(--muted); font-size: 15px; }
.err {
  max-width: 620px; margin: 60px auto; padding: 22px 26px; border-radius: var(--radius);
  border: 1px solid #f0c9c9; background: #fdf3f3; color: #8c3a3a; font-size: 14.5px;
}
.to-top {
  position: fixed; right: 22px; bottom: 22px; width: 42px; height: 42px; border-radius: 50%;
  background: #fff; border: 1px solid var(--line); box-shadow: var(--shadow); cursor: pointer;
  color: var(--accent); font-size: 17px; display: none; align-items: center; justify-content: center;
  z-index: 40;
}
.to-top.show { display: flex; }

/* ---------- 响应式 ---------- */
@media (max-width: 940px) {
  .hero-grid, .about-grid, .join-box, .contact-grid { grid-template-columns: 1fr; gap: 34px; }
  .pi-card { grid-template-columns: 1fr; gap: 26px; }
  .pi-photo { max-width: 220px; }
  .rs-inner { grid-template-columns: 1fr; }
  .rs-thumb { border-right: none; border-bottom: 1px solid var(--line-soft); padding: 22px; }
  .rs-thumb img { max-height: 106px; }
  .hero h1 { font-size: 34px; }
  section { padding: 62px 0; }
  .nav-links {
    display: none; position: absolute; top: 66px; left: 0; right: 0; background: #fff;
    border-bottom: 1px solid var(--line); flex-direction: column; padding: 10px 16px; gap: 2px;
  }
  .nav-links.open { display: flex; }
  .nav-toggle { display: block; }
  .pi-cols { grid-template-columns: 1fr; }
  .hero-stats { grid-template-columns: repeat(2, 1fr); }
  .pub { grid-template-columns: 1fr; }
  .pub-side { flex-direction: row; align-items: center; justify-content: flex-start; gap: 14px; }
  .topic-pills { flex-direction: row; }
}
@media (max-width: 560px) {
  .sec-head h2 { font-size: 25px; }
  .hero h1 { font-size: 29px; }
  .news-item { grid-template-columns: 1fr; gap: 3px; }
  .pi-card { padding: 22px; }
}

/* ---------- 打印 ---------- */
@media print {
  .nav, .to-top, .pub-bar, footer { display: none; }
  section { padding: 20px 0; page-break-inside: avoid; }
}