/* Layout: one pinned stage, copy left, WebGL billet right; seven scroll stations. Single dark gunmetal look. */
:root{
  /* Gunmetal: near-black blue-grey ground, neutral steel, one muted amber accent */
  --bg:#121820; --bg-deep:#0B0F15; --fg:#ECEFF3; --muted:#98A2B0; --line:rgba(255,255,255,.14);
  --grid-fine:rgba(255,255,255,.045); --grid-major:rgba(255,255,255,.09);
  --accent:#F0A35C; --steel:#c9ccd1; --steel-tint:#2c323a; --rim:#F0A35C; --shadow:rgba(0,0,0,.55);
  --sans:'IBM Plex Sans','Helvetica Neue',Arial,sans-serif; --mono:'IBM Plex Mono',Menlo,Consolas,monospace;
  color-scheme:dark;
}
html,body{margin:0}
body{background:var(--bg);color:var(--fg);font-family:var(--sans);overflow-x:hidden;
  background-image:linear-gradient(var(--grid-fine) 1px,transparent 1px),linear-gradient(90deg,var(--grid-fine) 1px,transparent 1px),linear-gradient(var(--grid-major) 1px,transparent 1px),linear-gradient(90deg,var(--grid-major) 1px,transparent 1px);transition:background-color .4s,color .4s;
  background-size:32px 32px,32px 32px,160px 160px,160px 160px}
a{color:var(--fg);transition:color .18s,background-color .18s,border-color .18s}a:hover{color:var(--accent)}
.gutter{padding-left:max(16px,env(safe-area-inset-left,0px));padding-right:max(16px,env(safe-area-inset-right,0px))}
header{position:sticky;top:env(safe-area-inset-top,0px);z-index:10;display:flex;align-items:center;justify-content:space-between;gap:24px;box-sizing:border-box;height:68px;padding-block:0;border-bottom:1px solid var(--line);background:color-mix(in srgb,var(--bg) 82%,transparent);backdrop-filter:blur(10px)}
body::before{content:"";position:fixed;inset:0 0 auto;height:env(safe-area-inset-top,0px);z-index:10;background:var(--bg)}
.inner{max-width:1344px;margin:0 auto;width:100%;box-sizing:border-box;padding-inline:32px}
.brand{display:flex;align-items:center;gap:12px;text-decoration:none;font-weight:600;font-size:18px;letter-spacing:-.01em}
.btn{display:inline-flex;align-items:center;text-decoration:none;font-size:15px;font-weight:600;color:var(--bg-deep);background:var(--fg);padding:14px 22px;border-radius:4px;min-height:48px;box-sizing:border-box}
.btn:hover{background:var(--accent);color:var(--bg-deep)}
.btn.ghost{color:var(--fg);background:transparent;border:1px solid rgba(255,255,255,.4);font-weight:500}
.btn.ghost:hover{background:transparent;color:var(--accent);border-color:var(--accent)}
footer nav a:hover,.brand:hover{color:var(--accent)}
.btn.sm{font-size:14px;padding:10px 16px;min-height:0}
#mill{position:relative;height:700vh;margin-top:-68px}
.stage{position:sticky;top:0;height:100vh;box-sizing:border-box;display:grid;grid-template-columns:minmax(0,.9fr) minmax(0,1.1fr);gap:40px;align-items:center;max-width:1344px;margin:0 auto;padding:72px 32px 24px}
.stage-wrap{position:sticky;top:0;height:100vh}
.stage-wrap .stage{position:relative;z-index:1;pointer-events:none}.stage-wrap .stage a,.stage-wrap .stage button{pointer-events:auto}
.copy{position:relative;min-height:380px}
.copy>div{position:absolute;left:0;right:0;top:50%;translate:0 -50%;display:flex;flex-direction:column;gap:20px;max-width:520px;opacity:0;will-change:opacity,transform}
.eyebrow{font-family:var(--mono);font-size:12px;letter-spacing:.12em;color:var(--accent)}
h1{margin:0;font-size:clamp(40px,5.2vw,68px);line-height:1;font-weight:600;letter-spacing:-.035em;text-wrap:balance}
h2{margin:0;font-size:clamp(32px,3.6vw,48px);line-height:1.04;font-weight:600;letter-spacing:-.03em;text-wrap:balance}
p{margin:0;font-size:18px;line-height:1.55;color:var(--muted);text-wrap:pretty;max-width:460px}
.row{display:flex;flex-wrap:wrap;gap:12px}
.hint{display:flex;align-items:center;gap:10px;font-family:var(--mono);font-size:12px;letter-spacing:.08em;color:rgba(243,247,255,.62)}
canvas#billet3d{position:absolute;inset:0;display:block;width:100%;height:100%;z-index:0}
.rail{position:absolute;right:max(16px,env(safe-area-inset-right,0px));top:50%;translate:0 -50%;display:flex;flex-direction:column;gap:18px;font-family:var(--mono);font-size:10px;letter-spacing:.1em}
.rail div{display:flex;align-items:center;gap:10px;opacity:.35;transition:opacity .3s}
.rail span{width:18px;height:1px;background:currentColor}
footer{border-top:1px solid var(--line);background:var(--bg-deep)}
footer .inner{display:flex;flex-wrap:wrap;justify-content:space-between;gap:16px 32px;align-items:center;padding-block:40px;font-size:14px;color:var(--muted)}
footer nav{display:flex;gap:24px}footer nav a{text-decoration:none;color:rgba(243,247,255,.8)}
.mono{font-family:var(--mono);font-size:12px;letter-spacing:.06em}
:focus-visible{outline:2px solid var(--accent);outline-offset:3px}
@media (max-width:900px){.stage{grid-template-columns:1fr;align-content:end;gap:0;padding-top:72px;padding-bottom:max(28px,env(safe-area-inset-bottom,0px))}.copy{min-height:min(44vh,360px)}.copy>div{top:auto;bottom:0;translate:none;max-width:none}.copy p{font-size:16px}.rail{display:none}}
@media (max-width:560px){header .btn.ghost{display:none}h1{font-size:40px}h2{font-size:30px}.btn{padding:12px 18px;min-height:44px;font-size:14px}}
@media (prefers-reduced-motion:reduce){#mill{height:auto}.stage-wrap{position:relative;height:auto}.stage{position:relative;height:auto;display:block;padding-top:48px}.copy{min-height:0}.copy>div{position:relative;top:auto;translate:none;opacity:1!important;transform:none!important;margin-bottom:56px}canvas#billet3d{position:relative;height:420px;margin-bottom:40px}}