/* ============================================================
   王健 Jian Wang — Academic Homepage
   风格参考 huihongxun.github.io：白底 · 学术蓝 · 衬线标题 · 内容优先
   v2 — 字体升级 Source Serif 4 · 排版精修 · 滚动渐入 · 微交互
   ============================================================ */

:root{
  /* ---- Color ---- */
  --c-bg:        #fcfcfd;
  --c-bg-alt:    #f5f7fa;
  --c-bg-warm:   #faf9f7;
  --c-ink:       #1a1f2e;
  --c-ink-soft:  #4a5366;
  --c-mute:      #8893a8;
  --c-line:      #e8ecf2;
  --c-line-soft: #f0f3f8;
  --c-blue:      #1a56a8;
  --c-blue-deep: #154478;
  --c-blue-soft: #2f7bc8;
  --c-blue-bg:   #eef3fb;
  --c-blue-tint: #f5f8fc;
  --c-gold:      #a67c00;
  --c-gold-bg:   #fbf6e9;
  --c-purple:    #6b4f9a;
  --c-purple-bg: #f3eff9;
  --c-green:     #2d8c5c;
  --c-green-bg:  #eaf5ef;

  /* ---- Shadow ---- */
  --shadow-xs: 0 1px 2px rgba(26,31,46,.04);
  --shadow-sm: 0 1px 3px rgba(26,31,46,.05), 0 4px 12px rgba(26,31,46,.04);
  --shadow-md: 0 6px 24px rgba(26,31,46,.08);
  --shadow-lg: 0 12px 40px rgba(26,31,46,.1);

  /* ---- Radius ---- */
  --radius-sm: 6px;
  --radius:    10px;
  --radius-lg: 14px;
  --radius-xl: 20px;

  /* ---- Layout ---- */
  --maxw:    1100px;
  --maxw-rd: 72ch;  /* 阅读最佳宽度 */

  /* ---- Type ---- */
  --font-sans:  'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Microsoft YaHei', sans-serif;
  --font-serif: 'Source Serif 4', Georgia, 'Songti SC', 'SimSun', serif;
  --font-mono:  'JetBrains Mono', ui-monospace, 'Cascadia Code', monospace;

  /* ---- Spacing ---- */
  --sp-section: 80px;
  --sp-elem:    24px;
}

/* ===================== RESET ===================== */
*{box-sizing:border-box;margin:0;padding:0}
*::selection{background:var(--c-blue-bg);color:var(--c-blue-deep)}

html{
  scroll-behavior:smooth;
  scroll-padding-top:76px;
}
body{
  font-family:var(--font-sans);
  color:var(--c-ink);
  background:var(--c-bg);
  line-height:1.72;
  font-size:16px;
  font-feature-settings:'kern' 1, 'liga' 1, 'cv05' 1;
  -webkit-font-smoothing:antialiased;
  -moz-osx-font-smoothing:grayscale;
  text-rendering:optimizeLegibility;
  overflow-x:hidden;
}
a{color:var(--c-blue);text-decoration:none;transition:color .2s ease}
a:hover{color:var(--c-blue-soft)}
img{max-width:100%;display:block}
strong{font-weight:600;color:var(--c-ink)}

.container{max-width:var(--maxw);margin:0 auto;padding:0 28px}
.container.narrow{max-width:800px}

/* ===================== SCROLL REVEAL ===================== */
[data-reveal]{
  opacity:0;
  transform:translateY(24px);
  transition:opacity .6s cubic-bezier(.16,1,.3,1), transform .6s cubic-bezier(.16,1,.3,1);
}
[data-reveal].revealed{
  opacity:1;
  transform:translateY(0);
}

/* ===================== NAV ===================== */
.nav{
  position:sticky;top:0;z-index:100;
  background:rgba(252,252,253,.85);
  backdrop-filter:saturate(180%) blur(14px);
  -webkit-backdrop-filter:saturate(180%) blur(14px);
  border-bottom:1px solid var(--c-line);
  transition:box-shadow .3s ease;
}
.nav.scrolled{box-shadow:var(--shadow-sm)}

.nav-inner{
  max-width:var(--maxw);margin:0 auto;padding:0 28px;
  height:62px;display:flex;align-items:center;justify-content:space-between;
}
.brand{display:flex;align-items:baseline;gap:9px;font-family:var(--font-serif);font-weight:600;letter-spacing:.01em}
.brand-name{color:var(--c-ink);font-size:1.12rem}
.brand-cn{color:var(--c-mute);font-size:.85rem;font-weight:400}

.nav-links{display:flex;gap:2px;align-items:center}
.nav-links a{
  position:relative;
  color:var(--c-ink-soft);font-size:.9rem;font-weight:500;
  padding:8px 14px;border-radius:var(--radius-sm);transition:all .2s ease;
  letter-spacing:.01em;
}
.nav-links a::after{
  content:"";position:absolute;bottom:4px;left:50%;transform:translateX(-50%);
  width:0;height:2px;background:var(--c-blue);border-radius:1px;transition:width .25s ease;
}
.nav-links a:hover{color:var(--c-blue)}
.nav-links a:hover::after,.nav-links a.active::after{width:18px}
.nav-links a.active{color:var(--c-blue);font-weight:600}

.nav-toggle{display:none;flex-direction:column;gap:5px;background:none;border:0;cursor:pointer;padding:6px}
.nav-toggle span{width:22px;height:2px;background:var(--c-ink);border-radius:2px;transition:.25s}
.nav-toggle.open span:nth-child(1){transform:translateY(7px) rotate(45deg)}
.nav-toggle.open span:nth-child(2){opacity:0}
.nav-toggle.open span:nth-child(3){transform:translateY(-7px) rotate(-45deg)}

/* ===================== HERO ===================== */
.hero{
  padding:64px 0 48px;
  background:
    radial-gradient(ellipse 600px 300px at 80% 0%, var(--c-blue-tint), transparent 70%),
    linear-gradient(180deg, var(--c-bg) 0%, var(--c-bg-alt) 100%);
  position:relative;
}
.hero::before{
  content:"";position:absolute;inset:0;
  background-image:
    linear-gradient(var(--c-line-soft) 1px, transparent 1px),
    linear-gradient(90deg, var(--c-line-soft) 1px, transparent 1px);
  background-size:48px 48px;
  opacity:.5;pointer-events:none;
  mask-image:radial-gradient(ellipse 70% 50% at 50% 30%, #000 30%, transparent 80%);
  -webkit-mask-image:radial-gradient(ellipse 70% 50% at 50% 30%, #000 30%, transparent 80%);
}
.hero-grid{
  position:relative;
  display:grid;grid-template-columns:300px 1fr;gap:52px;align-items:start;
}

/* ---- Sidebar ---- */
.side{
  position:sticky;top:80px;
  display:flex;flex-direction:column;align-items:center;text-align:center;
  background:#fff;border:1px solid var(--c-line);
  border-radius:var(--radius-lg);padding:30px 24px 24px;
  box-shadow:var(--shadow-sm);
  transition:box-shadow .3s ease;
}
.side:hover{box-shadow:var(--shadow-md)}

.avatar{
  position:relative;width:132px;height:168px;border-radius:var(--radius);
  display:flex;align-items:center;justify-content:center;
  background:linear-gradient(135deg,var(--c-blue-bg),var(--c-bg-alt));
  box-shadow:0 4px 16px rgba(26,86,168,.15);
  margin-bottom:18px;overflow:hidden;
  border:1px solid var(--c-line);
}
.avatar-img{
  width:100%;height:100%;object-fit:cover;
  object-position:center 20%;
  border-radius:var(--radius);display:block;
  transition:transform .4s ease;
}
.side:hover .avatar-img{transform:scale(1.03)}
.avatar-initials{
  color:var(--c-blue);font-family:var(--font-serif);font-size:2.6rem;
  font-weight:600;letter-spacing:.04em;
}
.avatar-ring{
  position:absolute;inset:-7px;border:2px solid var(--c-blue-bg);
  border-radius:calc(var(--radius) + 7px);pointer-events:none;
}

.welcome{
  font-family:var(--font-serif);font-size:1.02rem;color:var(--c-ink);
  font-weight:500;margin-bottom:10px;letter-spacing:.01em;
}
.address p{
  font-size:.82rem;color:var(--c-ink-soft);line-height:1.55;
}
.address .addr-cn{color:var(--c-mute);margin-top:4px}

.follow{display:flex;justify-content:center;gap:14px;margin:20px 0}
.flink{
  display:flex;align-items:center;justify-content:center;
  width:42px;height:42px;border-radius:50%;
  color:var(--c-ink-soft);
  background:var(--c-bg-alt);border:1px solid var(--c-line);
  transition:all .2s cubic-bezier(.16,1,.3,1);
}
.flink:hover{
  color:#fff;background:var(--c-blue);border-color:var(--c-blue);
  transform:translateY(-3px);box-shadow:0 6px 16px rgba(26,86,168,.25);
}
.flink svg{flex-shrink:0;transition:transform .2s ease}
.flink:hover svg{transform:scale(1.1)}

/* scholar stats */
.scholar-stats{
  display:flex;justify-content:space-around;width:100%;position:relative;
  border-top:1px solid var(--c-line);padding:16px 0 24px;margin-top:6px;
}
.scholar-stats::after{
  content:attr(data-stamp);
  position:absolute;bottom:-20px;left:50%;transform:translateX(-50%);
  font-size:.58rem;color:var(--c-mute);white-space:nowrap;letter-spacing:.02em;
  font-family:var(--font-mono);
}
.stat{display:flex;flex-direction:column;align-items:center;gap:3px}
.stat-num{
  font-family:var(--font-serif);font-size:1.4rem;font-weight:600;
  color:var(--c-blue);line-height:1;
  font-feature-settings:'tnum' 1;
}
.stat-lbl{
  font-size:.62rem;color:var(--c-mute);
  text-transform:uppercase;letter-spacing:.08em;font-weight:500;
}
.stat-live{position:relative}
.stat-live::after{
  content:"";position:absolute;top:2px;right:-10px;width:6px;height:6px;border-radius:50%;
  background:var(--c-green);box-shadow:0 0 0 0 rgba(45,140,92,.6);
  animation:stat-pulse 2s infinite;
}
@keyframes stat-pulse{
  0%{box-shadow:0 0 0 0 rgba(45,140,92,.5)}
  70%{box-shadow:0 0 0 6px rgba(45,140,92,0)}
  100%{box-shadow:0 0 0 0 rgba(45,140,92,0)}
}

/* ---- Hero main ---- */
.hero-main{padding-top:2px}
.eyebrow{
  color:var(--c-blue);font-weight:600;font-size:.8rem;
  letter-spacing:.12em;text-transform:uppercase;
  margin-bottom:14px;
  display:inline-flex;align-items:center;gap:8px;
}
.eyebrow::before{
  content:"";width:24px;height:2px;background:var(--c-blue);
  border-radius:1px;display:inline-block;
}
.hero-main h1{
  font-family:var(--font-serif);font-size:2.85rem;font-weight:700;
  color:var(--c-ink);line-height:1.12;margin-bottom:8px;
  letter-spacing:-.015em;
}
.name-cn{
  font-size:1.6rem;color:var(--c-mute);font-weight:400;
  margin-left:8px;letter-spacing:.05em;
}
.aff{
  color:var(--c-ink-soft);font-size:1.02rem;margin-bottom:24px;
  font-weight:400;
}
.bio-en,.bio-cn{
  font-size:.94rem;color:var(--c-ink-soft);margin-bottom:14px;
  max-width:680px;
}
.bio-en{
  font-family:var(--font-sans);line-height:1.72;
}
.bio-cn{line-height:1.85}

.hero-cta{display:flex;gap:12px;margin-top:22px;flex-wrap:wrap}
.btn{
  display:inline-flex;align-items:center;gap:6px;
  font-weight:600;font-size:.88rem;padding:11px 24px;
  border-radius:var(--radius-sm);transition:all .25s cubic-bezier(.16,1,.3,1);
  letter-spacing:.01em;
}
.btn-primary{
  background:var(--c-blue);color:#fff;
  box-shadow:0 2px 8px rgba(26,86,168,.2);
}
.btn-primary:hover{
  background:var(--c-blue-deep);color:#fff;
  transform:translateY(-2px);box-shadow:0 6px 20px rgba(26,86,168,.3);
}
.btn-ghost{
  border:1.5px solid var(--c-blue);color:var(--c-blue);
  background:transparent;
}
.btn-ghost:hover{
  background:var(--c-blue-bg);transform:translateY(-1px);
}

/* ===================== SECTIONS ===================== */
.section{padding:var(--sp-section) 0}
.section-alt{background:var(--c-bg-alt)}
.section-head{
  display:flex;align-items:center;gap:18px;margin-bottom:36px;
}
.section-head h2{
  font-family:var(--font-serif);font-size:1.72rem;font-weight:600;
  color:var(--c-ink);white-space:nowrap;
  letter-spacing:-.01em;
}
.section-line{
  flex:1;height:1px;
  background:linear-gradient(90deg,var(--c-line) 0%,transparent 100%);
}

/* ---- About cards ---- */
.about-grid{
  display:grid;grid-template-columns:repeat(3,1fr);gap:22px;
}
.about-card{
  background:#fff;border:1px solid var(--c-line);
  border-radius:var(--radius);padding:26px 24px;
  box-shadow:var(--shadow-xs);
  transition:all .3s cubic-bezier(.16,1,.3,1);
}
.about-card:hover{
  box-shadow:var(--shadow-md);transform:translateY(-3px);
  border-color:var(--c-blue-bg);
}
.about-card h3{
  font-family:var(--font-serif);font-size:1.08rem;
  color:var(--c-blue);margin-bottom:10px;font-weight:600;
}
.about-card p{
  font-size:.88rem;color:var(--c-ink-soft);line-height:1.65;
}

/* ---- Research tags ---- */
.research-list{
  display:flex;flex-wrap:wrap;gap:10px;margin-bottom:20px;
}
.ri-tag{
  display:inline-flex;align-items:center;
  font-size:.86rem;font-weight:500;color:var(--c-blue);
  background:#fff;border:1px solid var(--c-blue-bg);border-radius:24px;
  padding:8px 18px;transition:all .2s ease;
  letter-spacing:.01em;
}
.ri-tag::before{
  content:"";width:6px;height:6px;border-radius:50%;
  background:var(--c-blue);margin-right:8px;flex-shrink:0;
  transition:transform .2s ease;
}
.ri-tag:hover{
  background:var(--c-blue);color:#fff;border-color:var(--c-blue);
  transform:translateY(-2px);box-shadow:0 4px 12px rgba(26,86,168,.2);
}
.ri-tag:hover::before{background:#fff;transform:scale(1.3)}
.research-cn{
  font-size:.88rem;color:var(--c-ink-soft);line-height:1.85;
  max-width:800px;
}

/* ===================== PUBLICATIONS ===================== */
.pub-note{
  font-size:.88rem;color:var(--c-mute);
  margin:-18px 0 20px;line-height:1.6;
}
.pub-filter{
  display:flex;gap:8px;flex-wrap:wrap;margin-bottom:24px;
}
.chip{
  font-size:.8rem;font-weight:500;color:var(--c-ink-soft);
  background:#fff;border:1px solid var(--c-line);
  border-radius:20px;padding:7px 16px;cursor:pointer;
  transition:all .2s ease;letter-spacing:.01em;
}
.chip:hover{border-color:var(--c-blue);color:var(--c-blue);transform:translateY(-1px)}
.chip.active{
  background:var(--c-blue);color:#fff;border-color:var(--c-blue);
  box-shadow:0 2px 8px rgba(26,86,168,.2);
}

.pub-list{list-style:none}
.pub-year{
  font-family:var(--font-serif);font-size:1.28rem;font-weight:600;
  color:var(--c-blue);
  margin:32px 0 6px;padding-bottom:8px;
  border-bottom:2px solid var(--c-blue-bg);
  list-style:none;letter-spacing:-.005em;
  display:flex;align-items:baseline;gap:10px;
}
.pub-year::after{
  content:"";flex:1;height:1px;
  background:linear-gradient(90deg,transparent,var(--c-line));
}
.pub-year:first-child{margin-top:0}
.pub-year.hidden{display:none}

.pub-item{
  display:flex;gap:16px;padding:20px 0;
  border-bottom:1px solid var(--c-line-soft);
  align-items:flex-start;
  transition:background .2s ease;
}
.pub-item:hover{background:var(--c-blue-tint)}
.pub-item.hidden{display:none}
.pub-kind{
  display:inline-block;font-size:.62rem;font-weight:600;
  color:var(--c-purple);background:var(--c-purple-bg);
  border-radius:var(--radius-sm);padding:2px 7px;
  margin-left:8px;vertical-align:middle;
  letter-spacing:.02em;text-transform:uppercase;
}
.pub-num{
  flex-shrink:0;width:32px;height:32px;border-radius:50%;
  background:var(--c-bg-alt);color:var(--c-mute);
  display:flex;align-items:center;justify-content:center;
  font-family:var(--font-mono);font-size:.78rem;font-weight:500;
  transition:all .2s ease;
}
.pub-item.first .pub-num{
  background:var(--c-blue-bg);color:var(--c-blue);font-weight:600;
}
.pub-main{flex:1;min-width:0}
.pub-title{
  font-size:.96rem;color:var(--c-ink);font-weight:600;
  line-height:1.5;margin-bottom:6px;letter-spacing:-.005em;
}
.pub-title-link{
  color:inherit;text-decoration:none;
  transition:color .15s ease;
}
.pub-title-link:hover{color:var(--c-blue)}
.pub-ext{
  display:inline-block;vertical-align:baseline;
  margin-left:3px;color:var(--c-mute);
  transition:color .15s ease;
}
.pub-title-link:hover .pub-ext{color:var(--c-blue)}
.pub-authors{
  font-size:.82rem;color:var(--c-mute);line-height:1.55;margin-bottom:5px;
}
.pub-authors .me{color:var(--c-blue);font-weight:600}
.pub-meta{
  font-size:.82rem;color:var(--c-ink-soft);line-height:1.55;
}
.pub-meta em{font-style:italic;color:var(--c-ink)}
.pub-cite{
  flex-shrink:0;font-family:var(--font-mono);font-size:.76rem;
  color:var(--c-gold);background:var(--c-gold-bg);
  border-radius:var(--radius-sm);padding:4px 10px;
  font-weight:500;white-space:nowrap;
  transition:transform .2s ease;
}
.pub-item:hover .pub-cite{transform:scale(1.05)}

.pub-stamp{
  margin-top:20px;text-align:center;
  font-size:.72rem;color:var(--c-mute);
  font-family:var(--font-mono);
  letter-spacing:.01em;opacity:.7;
  transition:opacity .3s ease;
}
.pub-stamp:empty{display:none}

/* ===================== TIMELINE ===================== */
.timeline{position:relative;padding-left:8px}
.timeline::before{
  content:"";position:absolute;left:8px;top:6px;bottom:6px;
  width:2px;background:linear-gradient(180deg,var(--c-blue) 0%,var(--c-line) 100%);
}
.tl-item{position:relative;padding:0 0 28px 40px}
.tl-item:last-child{padding-bottom:0}
.tl-date{
  position:absolute;left:40px;top:-2px;
  font-size:.74rem;font-weight:600;color:var(--c-blue);
  background:var(--c-bg-alt);padding:2px 0;
  font-family:var(--font-mono);letter-spacing:.01em;
}
.tl-item:first-child .tl-date{
  position:relative;left:auto;top:auto;display:inline-block;margin-bottom:6px;
}
.tl-dot{
  position:absolute;left:1px;top:4px;width:16px;height:16px;
  border-radius:50%;background:#fff;border:3px solid var(--c-blue);
  transition:all .25s ease;
}
.tl-item:hover .tl-dot{
  transform:scale(1.25);box-shadow:0 0 0 4px var(--c-blue-bg);
}
.tl-body{padding-top:26px}
.tl-body h4{
  font-family:var(--font-serif);font-size:1.02rem;
  color:var(--c-ink);margin-bottom:3px;font-weight:600;
}
.tl-body p{font-size:.86rem;color:var(--c-ink-soft)}

/* ===================== PROJECTS ===================== */
.proj-list{
  list-style:none;display:flex;flex-direction:column;gap:14px;
}
.proj-list li{
  display:flex;gap:16px;align-items:flex-start;background:#fff;
  border:1px solid var(--c-line);border-radius:var(--radius);
  padding:20px 24px;
  transition:all .25s cubic-bezier(.16,1,.3,1);
}
.proj-list li:hover{
  box-shadow:var(--shadow-md);transform:translateY(-2px);
  border-color:var(--c-blue-bg);
}
.proj-tag{
  flex-shrink:0;font-size:.7rem;font-weight:600;color:#fff;
  border-radius:var(--radius-sm);padding:5px 11px;
  white-space:nowrap;height:fit-content;
  letter-spacing:.02em;
}
.proj-tag.nat{background:#c0392b}
.proj-tag.prov{background:var(--c-blue)}
.proj-tag.lab{background:var(--c-green)}
.proj-tag.grid{background:var(--c-purple)}
.proj-list h4{
  font-size:.96rem;color:var(--c-ink);margin-bottom:3px;
  font-family:var(--font-sans);font-weight:600;
}
.proj-list p{font-size:.84rem;color:var(--c-mute);line-height:1.55}

/* ===================== JOIN / NEWS ===================== */
.notice-box{
  background:#fff;border:1px solid var(--c-line);
  border-left:4px solid var(--c-blue);
  border-radius:var(--radius);padding:28px 30px;
  box-shadow:var(--shadow-sm);
  transition:box-shadow .3s ease;
}
.notice-box:hover{box-shadow:var(--shadow-md)}
.notice-tag{
  font-size:.74rem;font-weight:700;color:var(--c-blue);
  letter-spacing:.12em;text-transform:uppercase;margin-bottom:12px;
}
.notice-box p{color:var(--c-ink-soft);margin-bottom:10px;line-height:1.7}
.notice-box .contact-line{
  font-size:.88rem;margin-top:16px;padding-top:16px;
  border-top:1px dashed var(--c-line);
}

.news-list{list-style:none}
.news-list li{
  position:relative;padding:12px 0 12px 100px;
  border-bottom:1px dashed var(--c-line);
  font-size:.9rem;color:var(--c-ink-soft);line-height:1.65;
}
.news-list li:last-child{border-bottom:0}
.news-list li:hover{color:var(--c-ink)}
.news-date{
  position:absolute;left:0;top:14px;
  font-family:var(--font-mono);font-size:.78rem;font-weight:600;
  color:var(--c-blue);width:86px;
}
.news-list i{color:var(--c-ink);font-style:italic;font-weight:500}

/* ===================== FOOTER ===================== */
.footer{
  background:var(--c-ink);color:#cfd6e4;
  padding:36px 0;text-align:center;
}
.footer-link{
  color:#fff;font-family:var(--font-serif);font-weight:500;
  font-size:1.05rem;
}
.footer-link:hover{color:#fff;text-decoration:underline}
.copy{
  font-size:.8rem;color:#8a93a6;margin-top:10px;
  letter-spacing:.01em;
}

/* ===================== RESPONSIVE ===================== */
@media(max-width:900px){
  :root{--sp-section:60px}
  .hero{padding:48px 0 36px}
  .hero-grid{grid-template-columns:1fr;gap:36px}
  .side{
    position:relative;top:0;
    flex-direction:column;align-items:center;text-align:center;
    max-width:340px;margin:0 auto;
  }
  .about-grid{grid-template-columns:1fr;gap:16px}
  .hero-main h1{font-size:2.2rem}
  .name-cn{display:block;font-size:1.3rem;margin-left:0;margin-top:4px}
  .section-head h2{font-size:1.42rem}
}
@media(max-width:640px){
  :root{--sp-section:48px}
  .container{padding:0 20px}
  .nav-inner{padding:0 20px;height:56px}
  .nav-links{
    display:none;position:absolute;top:56px;left:0;right:0;
    flex-direction:column;background:#fff;
    border-bottom:1px solid var(--c-line);padding:10px 20px;gap:2px;
    box-shadow:var(--shadow-md);
  }
  .nav-links.open{display:flex}
  .nav-links a{padding:12px 14px}
  .nav-links a::after{display:none}
  .nav-toggle{display:flex}
  .hero-main h1{font-size:1.85rem}
  .pub-item{flex-wrap:wrap;gap:10px}
  .pub-cite{order:3;margin-top:6px}
  .news-list li{padding-left:0}
  .news-date{position:relative;left:auto;top:auto;display:block;width:auto;margin-bottom:4px}
  .proj-list li{flex-wrap:wrap}
  .notice-box{padding:22px 20px}
}