/* ============================================================
   study.hemishthanki.com — hub for the Holo* explorers.
   Material 3 holographic theme, Google Sans. Shares the palette
   of HoloCell / HoloDNA / HoloComp / HoloTron.
   ============================================================ */
:root{
  --font:'Google Sans','Product Sans',Roboto,system-ui,-apple-system,'Segoe UI',sans-serif;
  --mono:'Google Sans Mono',ui-monospace,'SF Mono',Menlo,monospace;

  --bg:#04070f;
  --surface:#0b1220;
  --surface-1:#0e1626;
  --surface-2:#131f34;
  --outline:#25344d;
  --outline-soft:#1a2740;

  --primary:#38e1ff;
  --primary-dim:#1596b4;
  --secondary:#7c9dff;
  --accent:#ff4fd8;
  --accent-2:#5dffb0;
  --warn:#ffcf5d;

  --on-surface:#e8f0ff;
  --on-surface-var:#9fb2cf;
  --on-surface-dim:#6a7d9c;

  --r-m:16px; --r-l:24px; --r-xl:30px; --r-full:999px;
  --shadow:0 18px 50px rgba(0,0,0,.55);
}

*{box-sizing:border-box;-webkit-tap-highlight-color:transparent}
html{scroll-behavior:smooth}
html,body{margin:0;min-height:100%}
body{
  font-family:var(--font);
  background:var(--bg);
  color:var(--on-surface);
  -webkit-font-smoothing:antialiased;
  text-rendering:optimizeLegibility;
  overflow-x:hidden;
}
a{color:inherit;text-decoration:none}
.material-symbols-rounded{font-family:'Material Symbols Rounded';font-variation-settings:'FILL' 0,'wght' 400,'GRAD' 0,'opsz' 24;line-height:1;user-select:none;flex:none}

/* ===================== Backdrop ===================== */
.bg{position:fixed;inset:0;z-index:-1;overflow:hidden;background:
  radial-gradient(1200px 820px at 78% -12%, rgba(56,225,255,.12), transparent 60%),
  radial-gradient(1000px 720px at 6% 108%, rgba(255,79,216,.10), transparent 55%),
  var(--bg);}
.bg-grid{position:absolute;inset:-2px;
  background-image:
    linear-gradient(rgba(56,225,255,.055) 1px, transparent 1px),
    linear-gradient(90deg, rgba(56,225,255,.055) 1px, transparent 1px);
  background-size:44px 44px;
  mask-image:radial-gradient(ellipse 90% 75% at 50% 30%, #000 40%, transparent 85%);
  -webkit-mask-image:radial-gradient(ellipse 90% 75% at 50% 30%, #000 40%, transparent 85%);}
.bg-glow{position:absolute;border-radius:50%;filter:blur(90px);opacity:.5;
  animation:float 18s ease-in-out infinite}
.bg-glow-1{width:460px;height:460px;left:-120px;top:-80px;background:rgba(56,225,255,.25)}
.bg-glow-2{width:520px;height:520px;right:-160px;top:20%;background:rgba(255,79,216,.20);animation-delay:-6s}
.bg-glow-3{width:420px;height:420px;left:30%;bottom:-160px;background:rgba(124,157,255,.20);animation-delay:-11s}
@keyframes float{0%,100%{transform:translate(0,0)}33%{transform:translate(28px,-24px)}66%{transform:translate(-22px,20px)}}
#stars{position:absolute;inset:0;width:100%;height:100%}

/* ===================== Layout ===================== */
.wrap{max-width:1120px;margin:0 auto;padding:clamp(28px,6vw,72px) clamp(18px,4vw,40px) 48px}

/* ===================== Hero ===================== */
.hero{text-align:center;margin-bottom:clamp(34px,5vw,58px)}
.mark{position:relative;width:96px;height:96px;margin:0 auto 22px}
.mark-core{position:absolute;left:50%;top:50%;width:26px;height:26px;transform:translate(-50%,-50%);
  border-radius:50%;background:radial-gradient(circle at 40% 35%,#9af2ff,var(--primary) 55%,var(--primary-dim,#1596b4));
  box-shadow:0 0 26px rgba(56,225,255,.75)}
.mark-ring{position:absolute;inset:6px;border-radius:50%;border:2px solid transparent;
  border-top-color:var(--primary);border-right-color:rgba(56,225,255,.35);
  animation:spin 3.4s linear infinite}
.mark-ring-2{inset:6px;border-top-color:var(--accent);border-right-color:rgba(255,79,216,.3);
  transform:rotate(60deg);animation-duration:5.2s;animation-direction:reverse}
.mark-ring-3{inset:6px;border-top-color:var(--accent-2);border-right-color:rgba(93,255,176,.3);
  transform:rotate(120deg);animation-duration:4.3s}
@keyframes spin{to{transform:rotate(360deg)}}
@media (prefers-reduced-motion:reduce){.mark-ring,.bg-glow{animation:none}}

.eyebrow{font-size:13px;font-weight:500;letter-spacing:2.4px;text-transform:uppercase;
  color:var(--on-surface-var)}
.eyebrow .dot{color:var(--primary);margin:0 5px;font-weight:700}
.title{font-size:clamp(34px,7vw,64px);font-weight:700;line-height:1.04;letter-spacing:-.5px;
  margin:14px 0 0;
  background:linear-gradient(100deg,#eaf6ff 8%,var(--primary) 46%,var(--secondary) 78%,var(--accent));
  -webkit-background-clip:text;background-clip:text;color:transparent}
.lede{max-width:620px;margin:20px auto 0;font-size:clamp(15px,2.4vw,18px);line-height:1.6;
  color:var(--on-surface-var)}
.hero-meta{display:flex;flex-wrap:wrap;gap:10px 20px;justify-content:center;margin-top:26px}
.hm{display:inline-flex;align-items:center;gap:7px;font-size:13.5px;color:var(--on-surface-dim)}
.hm .material-symbols-rounded{font-size:19px;color:var(--primary)}

/* ===================== Cards ===================== */
.grid{display:grid;grid-template-columns:repeat(2,1fr);gap:clamp(16px,2.2vw,24px)}
.card{position:relative;display:flex;flex-direction:column;overflow:hidden;
  padding:clamp(22px,3vw,30px);border-radius:var(--r-l);
  background:linear-gradient(165deg,var(--surface-1),var(--surface) 82%);
  border:1px solid var(--outline-soft);box-shadow:var(--shadow);
  transition:transform .28s cubic-bezier(.2,.7,.3,1),border-color .28s,box-shadow .28s}
.card::before{content:"";position:absolute;inset:0;border-radius:inherit;padding:1px;
  background:linear-gradient(140deg,color-mix(in srgb,var(--c) 55%,transparent),transparent 42%);
  -webkit-mask:linear-gradient(#000 0 0) content-box,linear-gradient(#000 0 0);
  -webkit-mask-composite:xor;mask-composite:exclude;opacity:0;transition:opacity .28s;pointer-events:none}
.card-glow{position:absolute;width:280px;height:280px;right:-90px;top:-110px;border-radius:50%;
  background:radial-gradient(circle,color-mix(in srgb,var(--c) 42%,transparent),transparent 68%);
  filter:blur(20px);opacity:.4;transition:opacity .3s,transform .5s;pointer-events:none}
.card:hover,.card:focus-visible{transform:translateY(-6px);border-color:color-mix(in srgb,var(--c) 45%,var(--outline));
  box-shadow:0 26px 60px rgba(0,0,0,.6),0 0 40px color-mix(in srgb,var(--c) 22%,transparent)}
.card:focus-visible{outline:2px solid var(--c);outline-offset:3px}
.card:hover::before,.card:focus-visible::before{opacity:1}
.card:hover .card-glow{opacity:.7;transform:scale(1.12)}
.card:hover .card-icon{transform:translateY(-2px) scale(1.06)}
.card:hover .card-go{color:var(--c);gap:11px}
.card:hover .card-go .material-symbols-rounded{transform:translateX(4px)}

.card-top{display:flex;align-items:center;justify-content:space-between;gap:12px;margin-bottom:16px}
.card-icon{font-size:44px;color:var(--c);
  filter:drop-shadow(0 0 16px color-mix(in srgb,var(--c) 60%,transparent));
  transition:transform .28s}
.card-count{font-family:var(--mono);font-size:11.5px;letter-spacing:.3px;color:var(--on-surface-var);
  background:var(--surface-2);
  background:color-mix(in srgb,var(--c) 12%,var(--surface-2));border:1px solid var(--outline-soft);
  padding:5px 11px;border-radius:var(--r-full);white-space:nowrap}
.card-name{font-size:clamp(22px,3vw,27px);font-weight:700;margin:0;letter-spacing:-.2px}
.card-tag{font-size:12px;font-weight:500;letter-spacing:1.4px;text-transform:uppercase;
  color:var(--c);margin-top:3px;opacity:.92}
.card-desc{font-size:14.5px;line-height:1.62;color:var(--on-surface-var);margin:14px 0 0}
.card-topics{display:flex;flex-wrap:wrap;gap:7px;margin-top:16px}
.card-topics span{font-size:11.5px;color:var(--on-surface-var);background:var(--surface-2);
  border:1px solid var(--outline-soft);padding:4px 10px;border-radius:var(--r-full)}
.card-go{display:inline-flex;align-items:center;gap:7px;margin-top:20px;padding-top:16px;
  border-top:1px solid var(--outline-soft);font-size:14px;font-weight:500;color:var(--on-surface);
  transition:color .24s,gap .24s}
.card-go .material-symbols-rounded{font-size:19px;transition:transform .24s}

/* ===================== How-to strip ===================== */
.how{display:grid;grid-template-columns:repeat(4,1fr);gap:14px;margin-top:clamp(26px,4vw,40px)}
.how-item{display:flex;align-items:center;gap:13px;padding:16px 18px;border-radius:var(--r-m);
  background:var(--surface);
  background:color-mix(in srgb,var(--surface) 70%,transparent);border:1px solid var(--outline-soft)}
.how-item .material-symbols-rounded{font-size:26px;color:var(--primary);
  filter:drop-shadow(0 0 10px rgba(56,225,255,.4))}
.how-item div{display:flex;flex-direction:column;min-width:0}
.how-item strong{font-size:14px;font-weight:600}
.how-item span{font-size:12.5px;color:var(--on-surface-dim);line-height:1.35}

/* ===================== Footer ===================== */
.foot{display:flex;flex-wrap:wrap;align-items:center;justify-content:space-between;gap:14px;
  margin-top:clamp(34px,5vw,52px);padding-top:22px;border-top:1px solid var(--outline-soft)}
.foot-home{display:inline-flex;align-items:center;gap:8px;font-size:14px;font-weight:500;
  color:var(--on-surface-var);padding:9px 15px;border-radius:var(--r-full);
  border:1px solid var(--outline-soft);background:var(--surface);transition:border-color .2s,color .2s}
.foot-home:hover{color:var(--primary);border-color:var(--primary-dim,#1596b4)}
.foot-home .material-symbols-rounded{font-size:19px}
.foot-note{font-size:12.5px;color:var(--on-surface-dim)}

/* ===================== Responsive ===================== */
@media (max-width:760px){
  .grid{grid-template-columns:1fr}
  .how{grid-template-columns:repeat(2,1fr)}
}
@media (max-width:440px){
  .how{grid-template-columns:1fr}
  .hero-meta{gap:8px 14px}
}