/* Kalra Lab / QuantumBio — severe serif theme (Fraunces headings, Amiri body, oxblood) */
:root{
  --red:#A81E2D;
  --red-deep:#7f1622;
  --ink:#141414;
  --muted:#5c5750;
  --line:#dcd7cf;
  --bg:#ffffff;
  --paper:#faf8f4;
  --maxw:740px;
  --wide:1080px;
  --head:"Fraunces", Georgia, "Times New Roman", serif;
  --body:"Barlow", -apple-system, "Segoe UI", Helvetica, Arial, sans-serif;
  --label:"Montserrat", "Avenir Next", Helvetica, Arial, sans-serif;
}
*{box-sizing:border-box;}
html{scroll-behavior:smooth;}
body{
  margin:0;
  font-family:var(--body);
  color:var(--ink);
  background:var(--bg);
  font-size:16px;
  font-weight:400;
  line-height:1.8;
  text-rendering:optimizeLegibility;
}
a{color:var(--red);text-decoration:none;}
a:hover{color:var(--red-deep);text-decoration:underline;}
img{max-width:100%;display:block;}
.container{max-width:var(--maxw);margin:0 auto;padding:0 40px;}
h1,h2,h3,.page-title,.hero h1{
  font-family:var(--head);
  font-weight:600;
  font-variation-settings:"opsz" 144,"SOFT" 0,"WONK" 0;
}

/* ---------- Masthead + Nav ---------- */
header.site{position:sticky;top:0;z-index:50;background:#fff;}
.masthead{max-width:var(--maxw);margin:0 auto;padding:26px 40px 32px;
  display:flex;align-items:center;justify-content:flex-start;position:relative;}
.brand{display:flex;align-items:center;gap:16px;text-decoration:none;}
.brand:hover{text-decoration:none;}
.brand img{height:64px;width:auto;}
.brand .brand-txt{font-family:var(--head);font-weight:600;font-size:1.5rem;color:var(--ink);
  line-height:1.05;letter-spacing:.01em;text-align:left;
  font-variation-settings:"opsz" 144,"SOFT" 0,"WONK" 0;}
.brand .brand-txt span{display:block;font-family:var(--label);font-weight:500;font-size:.58rem;
  letter-spacing:.22em;text-transform:uppercase;color:var(--muted);margin-top:6px;
  font-variation-settings:normal;}
.hamburger{position:absolute;right:40px;top:50%;transform:translateY(-50%);
  display:none;background:none;border:0;cursor:pointer;padding:8px;}
.hamburger span{display:block;width:24px;height:1.5px;background:var(--ink);margin:6px 0;}
nav{background:#fff;}
nav ul{max-width:var(--wide);margin:0 auto;padding:0 40px;list-style:none;
  display:flex;justify-content:center;flex-wrap:wrap;gap:0;}
nav li{position:relative;}
nav>ul>li+li{border-left:0;}
nav a.navlink{display:block;padding:13px 18px;font-family:var(--head);font-weight:500;
  font-size:.95rem;letter-spacing:.01em;text-transform:none;color:var(--red);
  text-decoration:none;white-space:nowrap;font-variation-settings:"opsz" 40,"SOFT" 0,"WONK" 0;}
nav a.navlink:hover,nav li:hover>a.navlink{color:var(--red-deep);}
nav a.navlink.active{color:var(--red);box-shadow:inset 0 -2px 0 var(--red);}
nav ul ul{position:absolute;top:100%;left:50%;transform:translateX(-50%);background:#fff;border:0;
  box-shadow:none;margin-top:-1px;padding:6px 0 4px;min-width:170px;
  display:none;flex-direction:column;z-index:60;}
nav li:hover>ul{display:flex;}
nav ul ul li+li{border-left:0;}
nav ul ul a.navlink{padding:6px 16px;text-align:center;text-transform:none;letter-spacing:.01em;
  font-size:.95rem;line-height:1.3;box-shadow:none;font-family:var(--head);font-weight:500;color:var(--red);
  font-variation-settings:"opsz" 40,"SOFT" 0,"WONK" 0;}
nav ul ul a.navlink:hover{color:var(--red-deep);}
nav ul ul a.navlink.active{box-shadow:none;color:var(--red);}

/* ---------- Hero ---------- */
.hero{background:#fff;}
.hero .container{padding:58px 40px 30px;}
.hero h1{font-size:1.825rem;margin:0;line-height:1.15;color:var(--ink);text-align:center;}
.hero p.lead{font-family:var(--body);font-style:italic;font-size:1.2rem;color:var(--muted);
  max-width:600px;margin:24px 0 0;line-height:1.7;}
.hero-img{margin-top:38px;border:1px solid var(--line);overflow:hidden;}
.hero-img img{width:100%;height:auto;display:block;}

/* ---------- Page structure ---------- */
main{padding:44px 0 72px;}
.page-title{font-size:1.375rem;text-transform:uppercase;letter-spacing:.05em;
  color:var(--ink);margin:0 0 36px;line-height:1.15;text-align:center;}
h2.section{font-size:1.155rem;color:var(--ink);margin:44px 0 14px;line-height:1.25;text-align:center;}
main .container>h2.section:first-child{margin-top:8px;}
h3.sub{font-family:var(--label);font-size:.72rem;font-weight:600;text-transform:uppercase;
  letter-spacing:.2em;color:var(--red);text-align:center;
  padding-bottom:0;margin:40px 0 18px;font-variation-settings:normal;}
p{margin:0 0 20px;text-align:justify;-webkit-hyphens:auto;hyphens:auto;}
ol.refs li{text-align:justify;-webkit-hyphens:auto;hyphens:auto;}
.muted{color:var(--muted);}

/* research / value blocks — editorial, hairline-separated */
.theme{display:flex;flex-direction:column;gap:14px;padding:36px 0;}
.theme:first-of-type{padding-top:8px;}
.theme .theme-img{order:-1;}
.theme .theme-img img{width:100%;height:auto;border:0;}
.theme h2{margin-top:0;}
.value-block{display:grid;grid-template-columns:1fr 300px;gap:44px;align-items:center;padding:40px 0;}
.value-block:first-of-type{padding-top:8px;}
.value-block .vimg img{width:100%;height:auto;border:1px solid var(--line);}
.value-block:nth-of-type(even) .vimg{order:-1;}
.value-block .section{margin-top:0;}

/* people — square institutional portraits, left-aligned */
.grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(150px,1fr));gap:40px 28px;margin:26px 0 8px;}
.person{text-align:left;}
.person .ph{width:100%;aspect-ratio:1/1;overflow:hidden;background:var(--paper);
  border:1px solid var(--line);}
.person .ph img{width:100%;height:100%;object-fit:cover;}
.person .name{font-family:var(--head);font-weight:600;color:var(--ink);font-size:0.895rem;
  margin-top:14px;line-height:1.25;}
.person .aff{font-family:var(--body);font-style:italic;color:var(--muted);font-size:.85rem;margin-top:2px;}

/* courses offered */
.course-item{padding-bottom:22px;}
.course-item h2.section{margin-top:40px;}

/* collaborators — text list, no photos */
.collab-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(210px,1fr));
  gap:28px 22px;margin:26px 0;text-align:center;}
.collab-grid .cn{font-family:var(--head);font-weight:600;color:var(--ink);font-size:1rem;
  display:block;line-height:1.3;}
.collab-grid .cn a{color:var(--ink);text-decoration:none;}
.collab-grid .cn a:hover{color:var(--red);text-decoration:underline;}
.collab-grid .ca{font-family:var(--body);font-style:italic;color:var(--muted);font-size:.85rem;}

/* publications — kept card style, severe */
.pub{border:0;padding:12px 0;margin:6px 0;background:none;}
.pub .title{font-family:var(--head);font-weight:600;font-size:0.955rem;color:var(--ink);
  margin-bottom:6px;line-height:1.35;}
.pub .title a{color:var(--ink);}
.pub .title a:hover{color:var(--red);}
.pub .meta{font-family:var(--body);font-style:italic;color:var(--muted);font-size:.92rem;line-height:1.6;}
.pub .meta em{font-style:normal;color:var(--red);font-weight:700;}

/* PI / bio */
.bio{display:grid;grid-template-columns:280px 1fr;gap:50px;align-items:start;}
.bio .portrait img{width:100%;border:1px solid var(--line);}
.credentials{margin-top:24px;}
.credentials div{padding:6px 0;font-size:.95rem;line-height:1.5;}

/* contact — austere, no fill */
.contact{padding-top:10px;margin-top:16px;background:none;color:var(--ink);text-align:center;}
.contact h2{font-family:var(--head);font-size:1.155rem;text-transform:none;letter-spacing:normal;
  color:var(--ink);font-weight:600;text-align:center;margin:0 0 16px;
  font-variation-settings:"opsz" 144,"SOFT" 0,"WONK" 0;}
.contact p{color:var(--ink);margin-bottom:12px;text-align:center;}
.contact a{color:var(--red);}

/* course */
.btn{display:inline-block;background:var(--red);color:#fff;padding:15px 34px;font-family:var(--body);
  font-weight:700;letter-spacing:.14em;text-transform:uppercase;font-size:.8rem;text-decoration:none;margin:10px 0;}
.btn:hover{background:var(--red-deep);color:#fff;text-decoration:none;}
.flyer{margin:32px 0;border:1px solid var(--line);overflow:hidden;}
ol.refs{padding-left:24px;}
ol.refs li{margin-bottom:11px;color:var(--muted);font-size:.9rem;line-height:1.65;}
.faq{margin:20px 0;}
.faq .q{font-family:var(--head);font-weight:600;color:var(--ink);margin-bottom:4px;font-size:0.925rem;}
.credentials.grade{max-width:440px;}

/* ---------- Footer ---------- */
footer.site{background:#fff;padding:44px 0;margin-top:72px;}
footer.site .fcenter{display:flex;flex-direction:column;align-items:center;gap:16px;}
footer.site .social{display:flex;gap:20px;align-items:center;}
footer.site .social img{height:22px;width:22px;}
footer.site .iitd img{height:70px;width:70px;}
footer.site .footmail{font-family:var(--body);font-size:.92rem;color:var(--ink);}
footer.site .footmail:hover{color:var(--red);}
.contact a.eaddr{color:var(--ink);}
.contact a.eaddr:hover{color:var(--red);}
footer.site .copy{font-family:var(--label);font-size:.72rem;font-weight:500;color:var(--red);
  margin-top:26px;text-align:center;letter-spacing:.07em;text-transform:uppercase;line-height:1.7;}

/* ---------- Responsive ---------- */
@media(max-width:860px){
  :root{--maxw:100%;}
  body{font-size:15px;}
  .masthead{justify-content:flex-start;padding:16px 22px;}
  .container,.hero .container,nav ul{padding-left:22px;padding-right:22px;}
  .hamburger{display:block;}
  nav{display:none;}
  nav.open{display:block;}
  nav ul{flex-direction:column;padding-top:4px;padding-bottom:4px;}
  nav>ul>li+li{border-left:0;border-top:0;}
  nav a.navlink{padding:13px 4px;}
  nav a.navlink.active{box-shadow:none;}
  nav ul ul{position:static;transform:none;left:auto;margin-top:0;border:0;padding:2px 0 8px 24px;min-width:0;display:none;}
  nav ul ul a.navlink{text-align:left;padding:9px 6px;}
  nav li:hover>ul{display:none;}
  nav li.sub-open>ul{display:flex;}
  .value-block,.bio{grid-template-columns:1fr;gap:26px;}
  .value-block:nth-of-type(even) .vimg{order:0;}
  .hero h1{font-size:1.55rem;}
  .page-title{font-size:1.225rem;}
}