/*
CSIR Bharat — page chrome: header/nav, hero, about intro band, footer.
*/

/* ---------------------------------------------------------------
   Header
--------------------------------------------------------------- */
.topbar,.goldbar{
  height:var(--topbar-h);
  background:linear-gradient(90deg,var(--gold-dark),var(--gold),var(--gold-dark));
}
.topbar{position:fixed;inset:0 0 auto 0;z-index:101}
.site-header{
  position:fixed;inset:var(--topbar-h) 0 auto 0;z-index:100;height:var(--header-h);
  display:flex;align-items:center;
  background:rgba(248,244,234,.92);backdrop-filter:blur(10px);
  border-bottom:1px solid transparent;
  transition:height .3s var(--ease),background .3s var(--ease),border-color .3s var(--ease),box-shadow .3s var(--ease);
}
.site-header.is-stuck{height:68px;box-shadow:0 6px 26px rgba(21,27,43,.09);border-bottom-color:var(--line)}
.header-inner{display:flex;align-items:center;justify-content:space-between;gap:24px;width:100%;margin:0 auto;padding:0 var(--gut)}
.brand{flex:0 0 auto}
.brand img{height:70px;width:auto;transition:height .3s var(--ease)}
.site-header.is-stuck .brand img{height:36px}

.nav{flex:1 1 auto;display:flex;align-items:center;justify-content:center;gap:30px;min-width:0}
.nav a{
  position:relative;font-size:14px;font-weight:600;color:var(--navy);white-space:nowrap;
  letter-spacing:.02em;padding:6px 0;transition:color .25s var(--ease);
}
.nav a::after{
  content:"";position:absolute;left:0;bottom:0;height:2px;width:100%;
  background:var(--orange);transform:scaleX(0);transform-origin:right;
  transition:transform .3s var(--ease);
}
.nav a:hover{color:var(--orange-dark)}
.nav a:hover::after,.nav a.is-active::after{transform:scaleX(1);transform-origin:left}
.nav a.is-active{color:var(--orange-dark)}
.nav .home-ico{font-size:17px}

/* Disabled nav items */
.nav .nav-disabled{
  position:relative;font-size:14px;font-weight:600;color:var(--navy);
  letter-spacing:.02em;padding:6px 0;opacity:.45;cursor:not-allowed;user-select:none;
}

/* ---------------------------------------------------------------
   Nav dropdown (About → About Us / Our Team)
--------------------------------------------------------------- */
.nav-drop{position:relative}
.nav-drop__trigger{display:inline-flex !important;align-items:center;gap:6px}
.nav-drop__caret{width:9px;height:9px;flex:none;transition:transform .3s var(--ease)}
.nav-drop__caret path{fill:none;stroke:currentColor;stroke-width:1.6;stroke-linecap:round;stroke-linejoin:round}
.nav-drop.is-open .nav-drop__caret,
.nav-drop:focus-within .nav-drop__caret{transform:rotate(180deg)}

.nav-drop__menu{
  --drop-ease:cubic-bezier(.16,1,.3,1);
  position:absolute;top:calc(100% + 14px);left:50%;
  transform:translate(-50%,-6px) scale(.98);transform-origin:top center;
  min-width:210px;margin-top:0;padding:8px;border-radius:14px;
  background:var(--paper);border:1px solid var(--line);
  box-shadow:0 2px 6px rgba(21,27,43,.05),0 18px 44px rgba(21,27,43,.13);
  opacity:0;visibility:hidden;pointer-events:none;
  transition:opacity .18s var(--drop-ease),transform .22s var(--drop-ease),visibility .22s;
  z-index:120;
}
/* Hover bridge — spans the visual gap above the panel so hover is continuous. */
.nav-drop__menu::before{
  content:"";position:absolute;left:-14px;right:-14px;top:-18px;height:20px;
}
.nav-drop:focus-within .nav-drop__menu,
.nav-drop.is-open .nav-drop__menu{
  opacity:1;visibility:visible;pointer-events:auto;
  transform:translate(-50%,0) scale(1);
}
.nav-drop__menu a{
  display:block;padding:11px 16px;border-radius:9px;
  font-family:var(--f-body);font-size:14px;font-weight:600;letter-spacing:.01em;
  color:var(--navy);white-space:nowrap;
  transition:background .2s var(--drop-ease),color .2s var(--drop-ease),transform .2s var(--drop-ease);
}
.nav-drop__menu a+a{margin-top:2px}
.nav-drop__menu a::after{display:none}
.nav-drop__menu a:hover,.nav-drop__menu a:focus-visible{
  background:var(--paper-alt);color:var(--orange-dark);transform:translateX(2px);
}
.nav-drop__menu a:focus-visible{outline:2px solid var(--orange);outline-offset:-2px}
.nav-drop__menu a.is-active{color:var(--orange-dark);background:var(--paper-alt)}

@media (prefers-reduced-motion:reduce){
  .nav-drop__menu{transition:opacity .01s linear,visibility .01s;transform:translate(-50%,0) scale(1)}
  .nav-drop__menu a:hover{transform:none}
}

.burger{display:none;background:none;border:0;width:44px;height:44px;padding:9px;position:relative}
.burger span{display:block;height:2px;background:var(--navy);border-radius:2px;transition:transform .3s var(--ease),opacity .2s var(--ease)}
.burger span+span{margin-top:6px}
.burger[aria-expanded="true"] span:nth-child(1){transform:translateY(8px) rotate(45deg)}
.burger[aria-expanded="true"] span:nth-child(2){opacity:0}
.burger[aria-expanded="true"] span:nth-child(3){transform:translateY(-8px) rotate(-45deg)}

/* ---------------------------------------------------------------
   Hero
--------------------------------------------------------------- */
.hero{position:relative;min-height:100svh;display:flex;align-items:center;overflow:hidden;background:var(--navy-deep)}
.hero__media{position:absolute;inset:0;z-index:0}
.hero__media video,.hero__media img{width:100%;height:100%;object-fit:cover}
.hero__scrim{
  position:absolute;inset:0;z-index:1;
  background:linear-gradient(90deg,rgba(21,27,43,.86) 0%,rgba(21,27,43,.62) 45%,rgba(21,27,43,.34) 100%);
}
.hero__scrim::after{
  content:"";position:absolute;inset:auto 0 0 0;height:38%;
  background:linear-gradient(180deg,transparent,rgba(21,27,43,.55));
}
.hero__inner{position:relative;z-index:2;width:100%;max-width:var(--wrap);margin:0 auto;padding:calc(var(--header-h) + var(--topbar-h) + 40px) var(--gut) 96px;color:#fff}
.hero__eyebrow{
  font-size:12px;letter-spacing:.24em;text-transform:uppercase;font-weight:700;
  color:var(--orange);margin:0 0 18px;
}
.hero h1{
  font-family:var(--f-display);font-weight:700;margin:0 0 22px;
  font-size:clamp(34px,5.4vw,62px);line-height:1.1;max-width:16ch;
}
.hero h1 em{font-style:italic;color:var(--orange)}
.hero p{max-width:56ch;font-size:clamp(15px,1.5vw,18px);color:rgba(255,255,255,.84);margin:0 0 34px}
.hero__cta{display:flex;flex-wrap:wrap;gap:14px}

.hero__scroll{
  position:absolute;left:50%;bottom:26px;transform:translateX(-50%);z-index:2;
  color:rgba(255,255,255,.75);font-size:10px;letter-spacing:.22em;text-transform:uppercase;
  display:flex;flex-direction:column;align-items:center;gap:9px;
}
.hero__scroll i{display:block;width:1px;height:38px;background:linear-gradient(180deg,rgba(255,255,255,.7),transparent);animation:drop 2s var(--ease) infinite}
@keyframes drop{0%{transform:scaleY(0);transform-origin:top}50%{transform:scaleY(1);transform-origin:top}50.1%{transform-origin:bottom}100%{transform:scaleY(0);transform-origin:bottom}}

/* ---------------------------------------------------------------
   About Us — centered, image-free institutional layout
--------------------------------------------------------------- */
.about-us{position:relative;overflow:hidden}
.about-us::before,.about-us::after{
  content:"";position:absolute;left:50%;transform:translateX(-50%);
  width:min(640px,80%);height:1px;
  background:linear-gradient(90deg,transparent,var(--gold-dark),var(--gold),var(--gold-dark),transparent);
}
.about-us::before{top:0}
.about-us::after{bottom:0}
.about-us__glow{
  position:absolute;top:50%;left:50%;transform:translate(-50%,-50%);
  width:900px;height:900px;max-width:180vw;border-radius:50%;
  background:radial-gradient(circle,rgba(197,107,60,.09),transparent 65%);
  pointer-events:none;z-index:0;
}
.about-us__inner{position:relative;z-index:1;max-width:960px;margin:0 auto}
.about-us__body{margin-top:36px;text-align:left}
.about-us__body p{color:var(--muted);font-size:18px;line-height:1.9;margin:0 0 22px}
.about-us__body p:last-child{margin-bottom:0}
.about-us__body strong{color:var(--navy);font-weight:700}

/* Full-width band */
.band{position:relative;line-height:0}
.band img{display:block;width:100%;height:auto}

/* ---------------------------------------------------------------
   Footer
--------------------------------------------------------------- */
.site-footer{background:var(--navy-deep);color:rgba(255,255,255,.68);padding:78px 0 0}
.foot__grid{display:grid;grid-template-columns:1.5fr 1fr 1.2fr 1fr;gap:48px}
.foot__brand img{height:46px;width:auto;margin-bottom:22px}
.foot__brand p{font-size:15px;line-height:1.7;margin:0;max-width:34ch}
.foot h4{
  font-size:12px;font-weight:700;letter-spacing:.16em;text-transform:uppercase;
  color:#fff;margin:0 0 20px;
}
.foot ul{list-style:none;margin:0;padding:0}
.foot li{margin-bottom:11px}
.foot li a{font-size:15px;transition:color .25s var(--ease),padding-left .25s var(--ease)}
.foot li a:hover{color:var(--orange)}
.foot__links li a{position:relative;padding-left:0}
.foot__links li a:hover{padding-left:8px}
.foot address{font-style:normal;font-size:15px;line-height:1.75}

.social{display:flex;gap:11px;margin-top:24px}
.social a{
  width:38px;height:38px;border-radius:50%;display:grid;place-items:center;
  border:1px solid rgba(255,255,255,.18);color:rgba(255,255,255,.5);
  transition:background .3s var(--ease),border-color .3s var(--ease),color .3s var(--ease),transform .3s var(--ease);
}
.social a[aria-disabled="true"]{opacity:.45;cursor:not-allowed}
.social a:not([aria-disabled="true"]):hover{background:var(--orange);border-color:var(--orange);color:#fff;transform:translateY(-3px)}
.social svg{width:15px;height:15px;fill:currentColor}

.foot__bar{
  margin-top:64px;border-top:1px solid rgba(255,255,255,.1);
  padding:24px 0;display:flex;flex-wrap:wrap;gap:8px;justify-content:space-between;
  font-size:13.5px;color:rgba(255,255,255,.45);
}
.foot__bar a{color:rgba(255,255,255,.62)}
.foot__bar a:hover{color:var(--orange)}