/* Shared layout for the 3D intro pages. Brand tokens are set per page on :root. */
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth}
body{background:var(--bg);color:var(--fg);font-family:var(--font-body);-webkit-font-smoothing:antialiased;overflow-x:hidden}
#gl{position:fixed;inset:0;width:100vw;height:100vh;z-index:0;pointer-events:none}
.grain{position:fixed;inset:0;z-index:1;pointer-events:none;opacity:.06;
  background-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='160' height='160'%3E%3Cfilter id='n'%3E%3CfeTurbulence baseFrequency='.9' numOctaves='2'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E")}
.vignette{position:fixed;inset:0;z-index:1;pointer-events:none;background:radial-gradient(ellipse at center,transparent 40%,var(--bg) 100%)}

header{position:fixed;top:0;inset-inline:0;z-index:10;display:flex;align-items:center;justify-content:space-between;padding:20px clamp(16px,4vw,48px)}
.logo{font-family:var(--font-display);font-size:22px;letter-spacing:.02em;color:var(--fg);text-decoration:none}
.logo b{color:var(--accent)}
nav{display:flex;gap:10px;align-items:center}
.btn{display:inline-flex;align-items:center;gap:8px;padding:11px 18px;border-radius:999px;font:600 13px/1 var(--font-body);letter-spacing:.04em;text-decoration:none;cursor:pointer;border:1px solid var(--line);color:var(--fg);background:transparent;transition:.25s}
.btn:hover{border-color:var(--accent);color:var(--accent)}
.btn.primary{background:var(--accent);color:var(--on-accent);border-color:var(--accent)}
.btn.primary:hover{filter:brightness(1.1);color:var(--on-accent)}

main{position:relative;z-index:2}
section{min-height:100vh;display:flex;flex-direction:column;justify-content:flex-end;padding:0 clamp(16px,5vw,64px) 12vh}
section .inner{max-width:560px;opacity:0;transform:translateY(30px);transition:opacity .8s, transform .8s}
section.is-active .inner{opacity:1;transform:none}
section.align-end{align-items:flex-end;text-align:end}
.kicker{font:600 11px/1 var(--font-body);letter-spacing:.35em;text-transform:uppercase;color:var(--accent);margin-bottom:14px;display:flex;gap:10px;align-items:center}
.kicker::before{content:"";width:28px;height:2px;background:var(--accent)}
h1,h2{font-family:var(--font-display);font-weight:400;line-height:.95;letter-spacing:-.01em;text-transform:uppercase}
h1{font-size:clamp(44px,8vw,110px)}
h2{font-size:clamp(34px,5.5vw,72px)}
h1 em,h2 em{font-style:normal;color:var(--accent)}
p.lead{margin-top:16px;font-size:clamp(15px,1.3vw,18px);line-height:1.6;color:var(--muted)}
.actions{margin-top:26px;display:flex;flex-wrap:wrap;gap:10px}
section.align-end .actions{justify-content:flex-end}

.progress{position:fixed;inset-inline-end:clamp(12px,2vw,28px);top:50%;transform:translateY(-50%);z-index:10;display:flex;flex-direction:column;gap:10px}
.progress span{width:3px;height:22px;background:var(--line);border-radius:2px;transition:.3s}
.progress span.on{background:var(--accent);height:40px}
.scroll-hint{position:fixed;bottom:22px;left:50%;transform:translateX(-50%);z-index:10;font:600 10px/1 var(--font-body);letter-spacing:.4em;color:var(--muted);transition:opacity .4s}
.scrolled .scroll-hint{opacity:0}

.still section .inner{transition:none}
.still .scroll-hint{display:none}

/* Arabic / RTL */
[dir=rtl] body{font-family:var(--font-arabic)}
[dir=rtl] h1,[dir=rtl] h2{font-family:var(--font-arabic);font-weight:800;text-transform:none;line-height:1.15}
[dir=rtl] .kicker{letter-spacing:.05em}

/* No WebGL: still a readable page */
.no-webgl body{background:radial-gradient(circle at 70% 30%,color-mix(in srgb,var(--accent) 18%,transparent),var(--bg) 60%)}
.no-webgl section .inner{opacity:1;transform:none}

@media (max-width:768px){
  section{padding-bottom:10vh}
  .progress{display:none}
  nav .hide-sm{display:none}
}
@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  section .inner{transition:none}
}