:root{
  --v1:#7c3aed;   /* violet */
  --v2:#d946ef;   /* magenta */
  --v3:#4f46e5;   /* indigo */
  --v4:#6453a1;   /* muted violet-indigo */
  --bg:#0a0713;
  --bg2:#120a24;
  --panel:rgba(255,255,255,.04);
  --panel-brd:rgba(168,120,255,.16);
  --txt:#ece9f5;
  --muted:#a99fc4;
  --accent:#d946ef;
  --radius:18px;
  --maxw:1080px;
}
*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth}
body{
  font-family:"Inter",system-ui,-apple-system,"Segoe UI",Roboto,Helvetica,Arial,sans-serif;
  background:var(--bg);
  color:var(--txt);
  line-height:1.65;
  overflow-x:hidden;
  -webkit-font-smoothing:antialiased;
}
h1,h2,h3{font-family:Georgia,"Times New Roman",serif;line-height:1.2;font-weight:600;letter-spacing:-.5px}
a{color:inherit;text-decoration:none}

/* language visibility (ES / EN / DE / ZH) */
html[data-lang="en"] .lang-es,html[data-lang="en"] .lang-de,html[data-lang="en"] .lang-zh{display:none}
html[data-lang="es"] .lang-en,html[data-lang="es"] .lang-de,html[data-lang="es"] .lang-zh{display:none}
html[data-lang="de"] .lang-en,html[data-lang="de"] .lang-es,html[data-lang="de"] .lang-zh{display:none}
html[data-lang="zh"] .lang-en,html[data-lang="zh"] .lang-es,html[data-lang="zh"] .lang-de{display:none}

/* ---- animated energy background ---- */
#energy{position:fixed;inset:0;z-index:-2;width:100%;height:100%;display:block}
.bg-glow{
  position:fixed;inset:0;z-index:-3;
  background:
    radial-gradient(closest-side at 15% 20%, rgba(124,58,237,.35), transparent 70%),
    radial-gradient(closest-side at 85% 15%, rgba(217,70,239,.30), transparent 70%),
    radial-gradient(closest-side at 70% 85%, rgba(79,70,229,.35), transparent 70%),
    radial-gradient(closest-side at 30% 60%, rgba(100,83,161,.32), transparent 70%),
    linear-gradient(160deg,var(--bg),var(--bg2));
  background-size:200% 200%,200% 200%,200% 200%,200% 200%,100% 100%;
  animation:flow 22s ease-in-out infinite;
}
@keyframes flow{
  0%{background-position:0% 50%,100% 50%,50% 100%,20% 30%,0 0}
  50%{background-position:100% 50%,0% 50%,50% 0%,80% 70%,0 0}
  100%{background-position:0% 50%,100% 50%,50% 100%,20% 30%,0 0}
}

/* ---- nav ---- */
nav{
  position:sticky;top:0;z-index:50;
  display:flex;align-items:center;justify-content:space-between;
  padding:14px clamp(16px,4vw,40px);
  backdrop-filter:blur(14px);
  background:rgba(10,7,19,.55);
  border-bottom:1px solid var(--panel-brd);
}
.brand{font-family:Georgia,serif;font-weight:700;font-size:1.15rem;
  background:linear-gradient(90deg,var(--v1),var(--v2),var(--v3));
  -webkit-background-clip:text;background-clip:text;color:transparent}
.nav-links{display:flex;gap:22px;align-items:center;flex-wrap:wrap}
.nav-links a{font-size:.9rem;color:var(--muted);transition:color .2s}
.nav-links a:hover{color:var(--txt)}
.lang-wrap{position:relative;display:inline-flex;align-items:center}
.lang-wrap::after{content:"▾";position:absolute;right:12px;pointer-events:none;color:var(--accent);font-size:.7rem}
.lang-select{
  border:1px solid var(--accent);border-radius:999px;
  background:linear-gradient(100deg,rgba(124,58,237,.18),rgba(217,70,239,.18));
  color:var(--txt);cursor:pointer;
  padding:6px 28px 6px 14px;font-size:.8rem;font-weight:700;letter-spacing:.5px;transition:.2s;
  font-family:inherit;-webkit-appearance:none;appearance:none
}
.lang-select:hover{filter:brightness(1.2);box-shadow:0 0 0 3px rgba(217,70,239,.18)}
.lang-select option{background:var(--bg2);color:var(--txt)}
.nav-burger{display:none;background:none;border:none;color:var(--txt);font-size:1.5rem;cursor:pointer}

/* ---- layout ---- */
section{max-width:var(--maxw);margin:0 auto;padding:clamp(56px,9vw,110px) clamp(18px,4vw,32px)}
.eyebrow{
  text-transform:uppercase;letter-spacing:3px;font-size:.72rem;font-weight:700;
  color:var(--accent);margin-bottom:14px;display:block
}
.section-title{font-size:clamp(1.7rem,4vw,2.5rem);margin-bottom:8px}
.section-lead{color:var(--muted);max-width:60ch;margin-bottom:36px}

/* ---- hero ---- */
.hero{min-height:88vh;display:flex;align-items:center}
.hero-inner{display:grid;grid-template-columns:1.25fr .85fr;gap:clamp(28px,5vw,56px);align-items:center;width:100%}
.hero-text{display:flex;flex-direction:column;gap:24px}
.hero-photo{position:relative;justify-self:center;width:min(340px,74vw);aspect-ratio:1/1}
.hero-photo .pf{position:absolute;inset:0;width:100%;height:100%;object-fit:cover;object-position:center 25%;
  border-radius:26px;border:1px solid var(--panel-brd);display:block;
  box-shadow:0 30px 80px -30px rgba(217,70,239,.6);
  opacity:0;transition:opacity 1.2s ease}
.hero-photo .pf.active{opacity:1}
.hero-photo::after{content:"";position:absolute;inset:-16px;border-radius:34px;z-index:-1;
  background:linear-gradient(135deg,var(--v1),var(--v2),var(--v3));filter:blur(38px);opacity:.5}
@media(max-width:820px){
  .hero-inner{grid-template-columns:1fr;gap:30px}
  .hero-photo{order:-1;width:min(210px,55vw)}
}
/* ---- talk photos ---- */
.talk-photos{display:grid;grid-template-columns:1fr 1fr;gap:16px;margin-bottom:34px}
.talk-photos figure{margin:0;border-radius:16px;overflow:hidden;border:1px solid var(--panel-brd);background:var(--panel);transition:.25s}
.talk-photos figure:hover{border-color:var(--accent);transform:translateY(-3px)}
.talk-photos img{width:100%;height:250px;object-fit:cover;display:block}
.talk-photos figcaption{font-size:.82rem;color:var(--muted);padding:11px 15px}
@media(max-width:640px){.talk-photos{grid-template-columns:1fr}.talk-photos img{height:220px}}
.hero h1{font-size:clamp(2.4rem,7vw,4.4rem);
  background:linear-gradient(100deg,#fff 20%,var(--v2) 55%,var(--v3) 90%);
  -webkit-background-clip:text;background-clip:text;color:transparent}
.hero-role{font-size:clamp(1rem,2.5vw,1.25rem);color:var(--accent);font-weight:600}
.hero-sub{font-size:clamp(1.05rem,2.5vw,1.35rem);color:var(--muted);max-width:62ch}
.hero-tags{display:flex;flex-wrap:wrap;gap:10px;margin-top:6px}
.tag{font-size:.82rem;padding:7px 14px;border:1px solid var(--panel-brd);border-radius:999px;color:var(--muted);background:var(--panel)}
.hero-cta{display:flex;gap:14px;flex-wrap:wrap;margin-top:12px}
.btn{
  padding:12px 24px;border-radius:999px;font-weight:600;font-size:.95rem;cursor:pointer;transition:.2s;
  border:1px solid var(--panel-brd);display:inline-flex;align-items:center;gap:8px
}
.btn-primary{background:linear-gradient(100deg,var(--v1),var(--v2));border:none;color:#fff}
.btn-primary:hover{filter:brightness(1.12);transform:translateY(-2px)}
.btn-ghost{color:var(--txt)}
.btn-ghost:hover{border-color:var(--accent);transform:translateY(-2px)}

/* ---- cards / grids ---- */
.grid{display:grid;gap:18px}
.grid-2{grid-template-columns:repeat(auto-fit,minmax(280px,1fr))}
.grid-3{grid-template-columns:repeat(auto-fit,minmax(230px,1fr))}
.card{
  background:var(--panel);border:1px solid var(--panel-brd);border-radius:var(--radius);
  padding:24px;transition:.25s;position:relative;overflow:hidden
}
.card:hover{transform:translateY(-4px);border-color:var(--accent);box-shadow:0 18px 50px -20px rgba(217,70,239,.5)}
.card h3{font-size:1.12rem;margin-bottom:8px}
.card p{color:var(--muted);font-size:.94rem}
.card .icon{font-size:1.6rem;margin-bottom:12px;display:block}

/* about */
.about-grid{display:grid;grid-template-columns:1.4fr 1fr;gap:40px;align-items:start}
.about-grid p{color:var(--muted);margin-bottom:16px}
.about-grid strong{color:var(--txt)}
.facts{display:flex;flex-direction:column;gap:14px}
.fact{background:var(--panel);border:1px solid var(--panel-brd);border-radius:14px;padding:16px 18px}
.fact .k{font-size:.72rem;text-transform:uppercase;letter-spacing:2px;color:var(--accent);font-weight:700}
.fact .val{font-size:.98rem;color:var(--txt);margin-top:2px}

/* publications */
.pub{border-left:2px solid var(--panel-brd);padding:0 0 26px 22px;position:relative}
.pub::before{content:"";position:absolute;left:-7px;top:5px;width:12px;height:12px;border-radius:50%;
  background:linear-gradient(120deg,var(--v2),var(--v3))}
.pub .year{font-size:.75rem;font-weight:700;color:var(--accent);letter-spacing:1px}
.pub h3{font-size:1.05rem;margin:4px 0 6px}
.pub .authors{font-size:.88rem;color:var(--muted)}
.pub .authors b{color:var(--txt);text-decoration:underline;text-decoration-color:var(--accent);text-underline-offset:3px;text-decoration-thickness:2px}
.pub .venue{font-size:.85rem;color:var(--muted);font-style:italic;margin-top:3px}
.pub .links{margin-top:8px;display:flex;gap:14px;flex-wrap:wrap}
.pub .links a{font-size:.8rem;color:var(--accent);border:1px solid var(--panel-brd);border-radius:999px;padding:3px 12px;transition:.2s}
.pub .links a:hover{background:var(--accent);color:#fff}
.subhead{font-family:Georgia,serif;font-size:1.15rem;color:var(--txt);margin:8px 0 24px;opacity:.9}
.pub-cards{margin-bottom:12px}
.pub-cards .card{display:flex;flex-direction:column}
.pub-cards .card .yv{font-size:.72rem;font-weight:700;color:var(--accent);letter-spacing:1px;text-transform:uppercase}
.pub-cards .card h3{font-size:1rem;margin:8px 0}
.pub-cards .card .auth{font-size:.82rem;color:var(--muted);margin-bottom:14px}
.pub-cards .card .auth b{color:var(--txt);text-decoration:underline;text-decoration-color:var(--accent);text-underline-offset:3px;text-decoration-thickness:2px}
.pub-cards .cardlinks{margin-top:auto;display:flex;gap:8px;flex-wrap:wrap;padding-top:8px}
.pub-cards .card .doi{font-size:.8rem;color:var(--accent);border:1px solid var(--panel-brd);border-radius:999px;padding:4px 13px;transition:.2s}
.pub-cards .card .doi:hover{background:var(--accent);color:#fff}

/* conferences */
.conf-list{display:grid;gap:12px}
.conf{display:grid;grid-template-columns:120px 1fr;gap:16px;background:var(--panel);border:1px solid var(--panel-brd);
  border-radius:14px;padding:16px 18px;transition:.2s}
.conf:hover{border-color:var(--accent)}
.conf .when{font-size:.8rem;font-weight:700;color:var(--accent)}
.conf .what{font-size:.94rem}
.conf .where{font-size:.82rem;color:var(--muted);margin-top:2px}
.count-badge{display:inline-block;font-size:.8rem;color:var(--muted);margin-left:8px}

/* awards */
.award-item{display:flex;gap:14px;align-items:flex-start;padding:14px 0;border-bottom:1px solid var(--panel-brd)}
.award-item:last-child{border:none}
.award-item .yr{min-width:92px;font-size:.8rem;font-weight:700;color:var(--accent)}
.award-item .txt{font-size:.94rem;color:var(--muted)}
.award-item .txt b{color:var(--txt)}

/* contact */
.contact-box{text-align:center;background:var(--panel);border:1px solid var(--panel-brd);border-radius:var(--radius);
  padding:clamp(32px,6vw,60px)}
.contact-box h2{margin-bottom:12px}
.contact-box p{color:var(--muted);max-width:50ch;margin:0 auto 26px}
.social{display:flex;gap:14px;justify-content:center;flex-wrap:wrap}

footer{border-top:1px solid var(--panel-brd);padding:34px 20px;text-align:center;color:var(--muted);font-size:.85rem}
footer a{color:var(--accent)}

.reveal{opacity:0;transform:translateY(26px);transition:opacity .7s ease,transform .7s ease}
.reveal.in{opacity:1;transform:none}

@media(max-width:760px){
  .about-grid{grid-template-columns:1fr}
  .conf{grid-template-columns:1fr}
  .conf .when{margin-bottom:-6px}
  .nav-links{position:fixed;top:60px;right:0;flex-direction:column;align-items:flex-start;gap:16px;
    background:rgba(10,7,19,.96);padding:24px 28px;border-left:1px solid var(--panel-brd);
    border-bottom:1px solid var(--panel-brd);border-radius:0 0 0 16px;transform:translateX(110%);transition:.3s}
  .nav-links.open{transform:none}
  .nav-burger{display:block}
}

/* ---- big navigation buttons ---- */
.biglinks{display:grid;grid-template-columns:1fr 1fr;gap:16px;margin-top:6px}
.biglinks.one{grid-template-columns:1fr}
.biglink{display:flex;flex-direction:column;gap:6px;padding:30px 28px;border-radius:var(--radius);border:1px solid var(--panel-brd);background:var(--panel);transition:.25s}
.biglink:hover{transform:translateY(-4px);border-color:var(--accent);box-shadow:0 18px 50px -20px rgba(217,70,239,.5)}
.biglink .bl-t{font-family:Georgia,serif;font-size:1.25rem;color:var(--txt)}
.biglink .bl-s{color:var(--muted);font-size:.9rem}
.biglink .bl-a{color:var(--accent);font-weight:700;margin-top:8px;font-size:.9rem}
.backhome{font-size:.9rem;color:var(--accent);font-weight:600}
@media(max-width:640px){.biglinks{grid-template-columns:1fr}}

.backbar{max-width:var(--maxw);margin:0 auto;padding:20px clamp(18px,4vw,32px) 0}

/* ============ THEME TOGGLE + LANGUAGE DROPDOWN ============ */
.theme-toggle{border:1px solid var(--panel-brd);border-radius:999px;background:transparent;color:var(--txt);cursor:pointer;width:34px;height:34px;font-size:.95rem;line-height:1;display:inline-flex;align-items:center;justify-content:center;transition:.2s}
.theme-toggle:hover{border-color:var(--accent);transform:translateY(-1px)}
.icon-moon{display:none}
html[data-theme="light"] .icon-sun{display:none}
html[data-theme="light"] .icon-moon{display:inline}
.flag{width:20px;height:14px;border-radius:2px;display:inline-block;vertical-align:middle;box-shadow:0 0 0 1px rgba(0,0,0,.14);flex:0 0 auto}
.lang-dd{position:relative}
.lang-btn{display:inline-flex;align-items:center;gap:7px;border:1px solid var(--accent);border-radius:999px;background:linear-gradient(100deg,rgba(124,58,237,.16),rgba(217,70,239,.16));color:var(--txt);cursor:pointer;padding:5px 11px;font-family:inherit;font-weight:700;font-size:.8rem;transition:.2s}
.lang-btn:hover{filter:brightness(1.08);box-shadow:0 0 0 3px rgba(217,70,239,.16)}
.lang-cur{display:inline-flex;align-items:center;gap:7px}
.lang-btn .caret{color:var(--accent);font-size:.7rem}
.lang-menu{position:absolute;right:0;top:calc(100% + 8px);list-style:none;margin:0;padding:6px;background:var(--bg2);border:1px solid var(--panel-brd);border-radius:14px;min-width:134px;display:none;z-index:60;box-shadow:0 20px 50px -18px rgba(0,0,0,.45)}
.lang-menu.open{display:block}
.lang-menu li{display:flex;align-items:center;gap:9px;padding:8px 11px;border-radius:9px;cursor:pointer;font-size:.85rem;color:var(--txt);white-space:nowrap}
.lang-menu li:hover{background:var(--panel)}

/* ============ LIGHT THEME ============ */
html[data-theme="light"]{
  --bg:#f5f2fc; --bg2:#e8e1f6;
  --panel:rgba(124,58,237,.06);
  --panel-brd:rgba(124,58,237,.22);
  --txt:#1c1533; --muted:#5c5578; --accent:#c026d3;
}
html[data-theme="light"] nav{background:rgba(255,255,255,.62)}
html[data-theme="light"] .nav-links{--panelbg:rgba(255,255,255,.97)}
html[data-theme="light"] .hero h1{background:linear-gradient(100deg,#2a1b4d 8%,var(--v2) 52%,var(--v3) 92%);-webkit-background-clip:text;background-clip:text;color:transparent}
html[data-theme="light"] .bg-glow{opacity:.85}
html[data-theme="light"] .card:hover,html[data-theme="light"] .biglink:hover{box-shadow:0 18px 50px -22px rgba(124,58,237,.4)}

/* mobile menu panel bg adapts to theme */
@media(max-width:760px){
  .nav-links{background:var(--panelbg, rgba(10,7,19,.96))}
}

/* ---- nav right cluster (controls stay visible on mobile) ---- */
.nav-right{display:flex;align-items:center;gap:16px}
@media(max-width:760px){
  .nav-right{gap:10px}
  .nav-burger{order:3}
}

/* ---- team ---- */
.team-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(250px,1fr));gap:18px}
.member{display:flex;flex-direction:column}
.avatar{width:72px;height:72px;border-radius:50%;display:flex;align-items:center;justify-content:center;font-family:Georgia,serif;font-size:1.4rem;font-weight:700;color:#fff;background:linear-gradient(135deg,var(--v1),var(--v2),var(--v3));margin-bottom:14px;box-shadow:0 10px 30px -12px rgba(217,70,239,.6)}
.member h3{font-size:1.15rem;margin-bottom:2px}
.member .mrole{font-size:.82rem;color:var(--accent);font-weight:600;margin-bottom:10px}
.member .mdesc{font-size:.92rem;color:var(--muted)}
/* ---- blog ---- */
.posts{display:grid;gap:16px}
.post{background:var(--panel);border:1px solid var(--panel-brd);border-radius:var(--radius);padding:24px;transition:.25s}
.post:hover{border-color:var(--accent)}
.post .date{font-size:.72rem;color:var(--accent);font-weight:700;letter-spacing:1px;text-transform:uppercase}
.post h3{font-size:1.25rem;margin:6px 0 8px}
.post p{color:var(--muted)}
.post .video{position:relative;aspect-ratio:16/9;border-radius:12px;overflow:hidden;margin-top:14px;border:1px solid var(--panel-brd)}
.post .video iframe{position:absolute;inset:0;width:100%;height:100%;border:0}
.empty{text-align:center;color:var(--muted);padding:48px 24px;border:1px dashed var(--panel-brd);border-radius:var(--radius)}

/* ---- team photos / carousels ---- */
.carousel{position:relative;overflow:hidden}
.cslide{position:absolute;inset:0;width:100%;height:100%;object-fit:cover;opacity:0;transition:opacity 1s ease}
.cslide.active{opacity:1}
.mphoto{aspect-ratio:1/1;border-radius:14px;margin-bottom:14px;border:1px solid var(--panel-brd)}
.team-banner{aspect-ratio:16/7;border-radius:var(--radius);margin-bottom:26px;border:1px solid var(--panel-brd)}
@media(max-width:640px){.team-banner{aspect-ratio:16/9}}

/* ---- soften animation in light mode (avoid clashing with text) ---- */
html[data-theme="light"] #energy{opacity:.4;filter:blur(1px)}
html[data-theme="light"] .bg-glow{opacity:.6}

.inlink{color:var(--accent);text-decoration:underline;text-underline-offset:2px;text-decoration-thickness:2px;font-weight:600}
.inlink:hover{filter:brightness(1.15)}