/* =========================================================
   ROBOKRITI // SILKY UI SYSTEM
   Premium festival-style interaction layer.
========================================================= */
:root{
  --silk-cyan:#18e7ff;
  --silk-violet:#8f7bff;
  --silk-ink:#02050d;
  --silk-line:rgba(255,255,255,.085);
  --silk-ease:cubic-bezier(.16,1,.3,1);
}
html{scroll-padding-top:88px}
body{background:
  radial-gradient(900px 500px at 80% -10%,rgba(24,231,255,.08),transparent 60%),
  radial-gradient(800px 500px at 10% 30%,rgba(143,123,255,.06),transparent 60%),
  #02050d;
}
body:before{opacity:.22;background-size:48px 48px;mask-image:linear-gradient(#000,transparent 88%)}

/* Refined glass header */
.site-header{
  height:82px;
  padding-inline:clamp(22px,5vw,76px);
  background:rgba(2,5,13,.48);
  border-bottom:1px solid rgba(255,255,255,.055);
  transition:height .55s var(--silk-ease),background .55s var(--silk-ease),
             box-shadow .55s var(--silk-ease),backdrop-filter .55s var(--silk-ease);
}
.site-header.scrolled{
  height:70px;
  background:rgba(2,5,13,.78);
  box-shadow:0 18px 70px rgba(0,0,0,.42),inset 0 -1px rgba(24,231,255,.09);
}
.brand{transition:transform .45s var(--silk-ease)}
.brand:hover{transform:translateY(-1px)}
.brand img{transition:transform .6s var(--silk-ease),filter .6s var(--silk-ease)}
.brand:hover img{transform:rotate(-4deg) scale(1.04);filter:drop-shadow(0 0 20px rgba(24,231,255,.28))}

/* Animated nav underline */
#mainNav a{position:relative;overflow:hidden;transition:color .35s var(--silk-ease),background .35s var(--silk-ease),transform .35s var(--silk-ease)}
#mainNav a:after{
  content:"";position:absolute;left:12px;right:12px;bottom:4px;height:1px;
  transform:scaleX(0);transform-origin:center;background:var(--silk-cyan);
  box-shadow:0 0 12px var(--silk-cyan);transition:transform .45s var(--silk-ease);
}
#mainNav a:hover:after,#mainNav a.active:after{transform:scaleX(1)}
#mainNav .nav-register{
  border:1px solid rgba(24,231,255,.25);
  box-shadow:0 0 0 rgba(24,231,255,0);
  transition:transform .4s var(--silk-ease),box-shadow .4s var(--silk-ease),background .4s var(--silk-ease);
}
#mainNav .nav-register:after{display:none}
#mainNav .nav-register:hover{transform:translateY(-2px);box-shadow:0 10px 35px rgba(24,231,255,.2)}

/* Hero: cinematic depth */
.hero{
  min-height:100svh;
  padding-left:clamp(24px,8vw,120px);
  padding-right:clamp(24px,8vw,120px);
  isolation:isolate;
}
.hero-content{max-width:900px;transform:translateZ(0)}
.hero h1{
  font-size:clamp(58px,9.2vw,126px);
  line-height:.86;
  letter-spacing:-.055em;
  text-wrap:balance;
}
.hero h1 span{
  background:linear-gradient(100deg,#fff 5%,var(--silk-cyan) 55%,#7bb9ff 100%);
  -webkit-background-clip:text;background-clip:text;color:transparent;
  filter:drop-shadow(0 0 28px rgba(24,231,255,.13));
}
.hero p{font-size:clamp(14px,1.25vw,17px);max-width:700px}
.phase-label{display:inline-flex;align-items:center;gap:10px}
.phase-label:before{content:"";width:30px;height:1px;background:var(--silk-cyan);box-shadow:0 0 10px var(--silk-cyan)}
.hero-actions{gap:14px}
.btn{
  position:relative;overflow:hidden;border-radius:999px;
  padding:14px 21px;
  transition:transform .5s var(--silk-ease),box-shadow .5s var(--silk-ease),border-color .5s var(--silk-ease);
}
.btn:before{
  content:"";position:absolute;inset:0;transform:translateX(-110%);
  background:linear-gradient(100deg,transparent,rgba(255,255,255,.22),transparent);
  transition:transform .7s var(--silk-ease);
}
.btn:hover:before{transform:translateX(110%)}
.btn>*{position:relative}
.btn:hover{transform:translateY(-3px) scale(1.01)}
.btn.primary{box-shadow:0 10px 35px rgba(24,231,255,.12)}
.btn.primary:hover{box-shadow:0 16px 50px rgba(24,231,255,.25)}
.btn.ghost{border-color:rgba(255,255,255,.11)}

/* Floating HUD/orbit */
.hero-visual{
  width:min(40vw,520px);height:min(40vw,520px);
  right:clamp(2%,8vw,120px);
  border-color:rgba(24,231,255,.13);
  transition:transform .9s var(--silk-ease),opacity .6s ease;
}
.visual-core{
  width:min(16vw,190px);height:min(16vw,190px);
  border-radius:34%;
  transition:transform .8s var(--silk-ease),box-shadow .8s var(--silk-ease);
}
.hero-visual:hover .visual-core{transform:scale(1.035) rotate(2deg);box-shadow:0 0 100px rgba(24,231,255,.18),inset 0 0 45px rgba(24,231,255,.08)}
.hero-grid{opacity:.72}

/* Ambient cursor spotlight, driven by JS */
.silk-cursor{
  position:fixed;z-index:2;width:420px;height:420px;border-radius:50%;
  pointer-events:none;opacity:0;
  background:radial-gradient(circle,rgba(24,231,255,.075),rgba(24,231,255,0) 68%);
  transform:translate3d(-50%,-50%,0);
  transition:opacity .35s ease;
  mix-blend-mode:screen;
}
.silk-cursor.visible{opacity:1}

/* Festival phase strip */
.phase-strip{position:relative;z-index:3;background:rgba(3,7,17,.76);backdrop-filter:blur(12px)}
.phase-strip>div{position:relative;overflow:hidden;transition:background .5s var(--silk-ease),transform .5s var(--silk-ease)}
.phase-strip>div:before{
  content:"";position:absolute;inset:0;opacity:0;
  background:radial-gradient(circle at 50% 0,rgba(24,231,255,.10),transparent 55%);
  transition:opacity .5s var(--silk-ease);
}
.phase-strip>div:hover{background:rgba(255,255,255,.018);transform:translateY(-2px)}
.phase-strip>div:hover:before{opacity:1}

/* Section rhythm */
.section{padding-top:clamp(88px,10vw,150px);padding-bottom:clamp(88px,10vw,150px)}
.section-head h2{font-size:clamp(34px,5.3vw,68px);letter-spacing:-.045em}
.section-head p{font-size:13px;line-height:1.9}

/* Magnetic/spotlight cards */
.arena-card,.leadership-feature,.core-card,.operations-grid article,.contact-card,.mentor-message{
  --px:50%;--py:50%;
  position:relative;
  isolation:isolate;
  transition:transform .65s var(--silk-ease),border-color .5s ease,box-shadow .65s var(--silk-ease);
}
.arena-card:before,.leadership-feature:before,.core-card:before,.operations-grid article:before,.contact-card:before{
  background:radial-gradient(280px circle at var(--px) var(--py),rgba(24,231,255,.105),transparent 58%),linear-gradient(135deg,rgba(24,231,255,.045),transparent 48%);
  opacity:1;transition:opacity .4s ease;
}
.arena-card:hover,.leadership-feature:hover,.core-card:hover,.operations-grid article:hover,.contact-card:hover{
  transform:translateY(-8px);
  border-color:rgba(24,231,255,.28);
}
.arena-card:after{
  transition:transform .8s var(--silk-ease),border-color .5s ease;
}
.arena-card:hover:after{transform:scale(1.18);border-color:rgba(24,231,255,.25)}
.arena-card h3,.leadership-feature h3,.core-card h3,.operations-grid h3,.contact-card h3{transition:transform .5s var(--silk-ease),color .5s ease}
.arena-card:hover h3,.leadership-feature:hover h3,.core-card:hover h3,.operations-grid article:hover h3{transform:translateX(3px)}

/* Scroll reveal: less blur, more glide */
.silk-reveal{opacity:0;transform:translate3d(0,34px,0) scale(.985)}
.silk-reveal.silk-in{opacity:1;transform:none;transition:opacity .9s var(--silk-ease),transform 1s var(--silk-ease)}

/* Footer / CTA */
.final-cta{border-radius:28px}
.final-cta .btn{margin-top:2px}
.footer{transition:background .4s ease}
.footer:hover{background:rgba(255,255,255,.018)}

/* Mobile */
@media(max-width:1000px){
  .hero-visual{width:430px;height:430px;right:-110px}
}
@media(max-width:800px){
  .site-header{height:70px}
  .site-header.scrolled{height:64px}
  .hero{min-height:100svh;padding-top:125px}
  .hero h1{font-size:clamp(46px,13vw,76px)}
  .hero-content{max-width:720px}
  .hero-visual{display:none}
  .silk-cursor{display:none}
}
@media(max-width:520px){
  .hero{padding-top:116px}
  .hero h1{font-size:clamp(43px,14.5vw,65px)}
  .hero-meta{gap:12px}
  .section{padding-top:76px;padding-bottom:76px}
  .final-cta{border-radius:20px;padding:58px 22px}
}
@media(prefers-reduced-motion:reduce){
  .silk-cursor{display:none}
  .silk-reveal{opacity:1;transform:none}
}