/* DEFXN shared desktop chrome: identity, orientation, then the run action. */
#scene .ark-header {
 display:flex;align-items:center;justify-content:space-between;
 position:absolute;top:0;left:0;right:0;
 gap:12px;height:76px;min-height:0;padding:14px max(20px,3.2cqw);z-index:20;
 border:0;background:transparent !important;box-sizing:border-box;pointer-events:none;
}
.ark-header::after {
 content:"";position:absolute;left:max(20px,3.2cqw);right:max(20px,3.2cqw);bottom:0;
 height:1px;background:linear-gradient(90deg,hsl(var(--primary) / .35),hsl(var(--border-subtle)) 24%,hsl(var(--border-subtle)) 76%,transparent);
}
.ark-studio-identity {
 display:inline-flex;align-items:center;justify-content:flex-start;gap:12px;
 width:auto;height:48px;flex:0 0 auto;margin-right:auto;padding:0 4px;text-decoration:none;
 border:0 !important;border-radius:7px;background:transparent !important;box-shadow:none !important;pointer-events:auto;
 color:hsl(var(--text-strong));
}
.ark-brand-lockup {display:flex;flex-direction:column;gap:5px;}
.ark-brand-wordmark {font:650 24px/.95 var(--font-sans,"Albert Sans",sans-serif);letter-spacing:.13em;color:hsl(var(--text-strong));}
.ark-brand-descriptor {font:500 8px/1 var(--mono-font,ui-monospace,monospace);letter-spacing:.15em;color:hsl(var(--text-muted));}
.header-core-links {
 display:flex;align-items:center;gap:3px;padding:4px;height:46px;box-sizing:border-box;
 border:1px solid hsl(var(--border-subtle));border-radius:9px;background:hsl(var(--canvas) / .65);pointer-events:auto;
}
#scene .ark-header .header-core-links a {
 position:relative;display:inline-flex;align-items:center;justify-content:center;gap:7px;height:36px;
 padding:0 clamp(9px,1.15cqw,17px);border:0;border-radius:6px;background:transparent;box-shadow:none !important;
 font:500 12px/1.2 var(--font-sans,"Albert Sans",sans-serif);letter-spacing:0;text-transform:none;text-decoration:none;
 color:hsl(var(--text-muted)) !important;transition:color 180ms,background-color 180ms;
}
#scene .ark-header .header-core-links a::after {content:none;}
#scene .ark-header .header-core-links a:is(:hover,:focus-visible,[aria-current="page"]) {
 color:hsl(var(--text-strong)) !important;background:hsl(var(--primary) / .1);
}
#scene .ark-header .header-core-links a[aria-current="page"] {box-shadow:inset 0 -2px hsl(var(--primary)) !important;}
#scene .ark-header .header-core-links .header-run-link {color:hsl(var(--text-strong)) !important;background:hsl(var(--primary) / .12);border:1px solid hsl(var(--primary) / .3);}
#scene .ark-header .header-core-links .header-run-link:is(:hover,:focus-visible) {background:hsl(var(--primary) / .23);border-color:hsl(var(--primary) / .6);}
#scene .nav-toggle {
 display:inline-flex; align-items:center; justify-content:center; width:40px; height:40px; padding:0;
 border:1px solid hsl(var(--border-default)); border-radius:var(--size-card-radius,8px);
 background:hsl(var(--canvas) / .72); color:hsl(var(--text-strong)); cursor:pointer;
 pointer-events:auto; transition:background-color 180ms ease,border-color 180ms ease;
}
#scene .nav-toggle:hover,
#scene .ark-header.nav-open .nav-toggle { background:hsl(var(--surface)); border-color:hsl(var(--text-strong) / .36); }
#scene .ark-header #primary-navigation {
 display:none; position:absolute; top:75px; right:max(20px,3.2cqw);
 width:min(620px,calc(100vw - 40px)); height:min(540px,calc(100dvh - 96px));
 min-height:min(280px,calc(100dvh - 80px)); padding:0; margin:0; overflow:hidden; box-sizing:border-box;
 border:1px solid hsl(var(--border-strong)); border-top:2px solid hsl(var(--primary) / .7);
 border-radius:var(--size-panel-radius,18px);
 background:linear-gradient(145deg,hsl(var(--surface)),hsl(var(--canvas)));
 box-shadow:0 28px 80px hsl(var(--canvas) / .7); pointer-events:auto;
 backdrop-filter:blur(18px); -webkit-backdrop-filter:blur(18px);
}
#scene .ark-header.nav-open #primary-navigation { display:block; }
#scene .ark-header .ark-link {
 position:relative; display:flex; align-items:center; gap:12px;
 min-width:0; min-height:35px; padding:3px 2px; counter-increment:nav-group;
 border-top:1px solid hsl(var(--border-subtle));
 border-radius:var(--size-card-radius,8px); background:none; color:hsl(var(--text-muted));
 font:500 10px/1.3 var(--mono-font,ui-monospace,monospace);
 letter-spacing:0; text-transform:uppercase; text-decoration:none;
 transition:color 180ms ease,background-color 180ms ease;
}
#scene .ark-header .ark-link::before {
 content:counter(nav-group, decimal-leading-zero);
 color:hsl(var(--text-muted) / .7); font-size:9px;
}
#scene .ark-header .ark-link::after { content:"↗"; margin-left:auto; color:hsl(var(--primary)); font-size:12px; }
:root[data-theme] #scene .ark-header .ark-link { color:hsl(var(--text-muted)) !important; }
:root[data-theme] #scene .ark-header .ark-link:is(:hover,[aria-current="page"]) { color:hsl(var(--text-strong)) !important; }
#scene .ark-header .ark-link[aria-current="page"]::before { color:hsl(var(--primary)); }
#scene .ark-header .ark-link:is(:hover,[aria-current="page"]) { background:hsl(var(--text-strong) / .045); }

#scene .ark-header a:focus-visible,
#scene .nav-toggle:focus-visible { outline:2px solid hsl(var(--primary)); outline-offset:4px; }
@media(max-width:700px) {
 .header-core-links { gap:16px; }
 #scene .ark-header .header-core-links a { font-size:9px; }
}
@media(max-width:620px) {
 #scene .ark-header { padding-inline:16px; }
 #scene .ark-header #primary-navigation { top:75px; right:16px; width:min(380px,calc(100vw - 32px)); }
 #scene .ark-header .ark-link { min-height:44px; }
}
@media(max-width:560px) { .header-core-links { display:none; } }
@media(prefers-reduced-motion:reduce) { #scene .ark-header .ark-link { transition:none; } }

/* The index is a stack of fixed-size views, never an expanding accordion. */
#scene .ark-header .nav-layer {
 position:absolute; inset:0; display:flex; flex-direction:column;
 padding:23px 27px 26px; box-sizing:border-box;
 overflow-y:auto; overscroll-behavior:contain;
 scrollbar-width:thin; scrollbar-color:hsl(var(--border-strong)) transparent;
}
#scene .ark-header .nav-layer[hidden] { display:none !important; }
#scene .ark-header .nav-layer-top { display:flex; align-items:center; justify-content:space-between; min-height:24px; }
#scene .ark-header .nav-layer-depth {
 margin-left:auto; color:hsl(var(--primary));
 font:600 9px/1.2 var(--mono-font,ui-monospace,monospace); letter-spacing:.15em;
}
#scene .ark-header .nav-layer-back {
 min-height:44px; padding:4px 8px; border:1px solid hsl(var(--border-default));
 border-radius:var(--size-card-radius,8px); background:transparent;
 color:hsl(var(--text-muted)); font:600 10px/1.2 var(--mono-font,ui-monospace,monospace);
 letter-spacing:.04em; cursor:pointer;
}
#scene .ark-header .nav-layer-back:hover { border-color:hsl(var(--primary) / .5); color:hsl(var(--text-strong)); }
#scene .ark-header .nav-layer-title {
 margin:12px 0 0; color:hsl(var(--text-strong));
 font:700 clamp(27px,3.2cqw,38px)/1.05 "Albert Sans",sans-serif;
 letter-spacing:-.05em;
}
#scene .ark-header .nav-layer-note {
 margin:7px 0 16px; color:hsl(var(--text-muted));
 font:400 12px/1.5 "Albert Sans",sans-serif;
}
#scene .ark-header .nav-layer-body {
 display:grid; flex:0 0 auto; min-height:0; gap:9px;
 grid-template-columns:repeat(4,minmax(0,1fr));
 grid-template-rows:none; grid-auto-rows:minmax(104px,auto);
 counter-reset:nav-group;
}
#scene .ark-header .nav-layer[data-nav-layer="index"] .nav-layer-body {
 grid-template-columns:repeat(3,minmax(0,1fr));
 grid-template-rows:repeat(3,minmax(95px,1fr));
}
#scene .ark-header .nav-layer-choice {
 position:relative; display:flex; flex-direction:column; align-items:flex-start;
 min-width:0; min-height:104px; padding:15px; text-align:left;
 border:1px solid hsl(var(--border-default)); border-radius:var(--size-card-radius,8px);
 background:linear-gradient(145deg,hsl(var(--raised) / .68),hsl(var(--surface) / .48));
 box-shadow:inset 0 1px hsl(var(--text-strong) / .045);
 color:hsl(var(--text-strong)); cursor:pointer;
 transition:background-color 180ms ease,border-color 180ms ease,transform 180ms ease;
}
#scene .ark-header .nav-layer-choice:is(:hover,:focus-visible) {
 border-color:hsl(var(--primary) / .65); background:hsl(var(--primary) / .12);
 transform:translateY(-2px);
}
#scene .ark-header .nav-layer[data-nav-layer="index"] .nav-layer-choice:nth-child(1) {
 grid-column:1/3; grid-row:1/3; border-color:hsl(var(--primary) / .44);
 background:radial-gradient(circle at 90% 0,hsl(var(--primary) / .16),transparent 58%),hsl(var(--raised) / .5);
}
#scene .ark-header .nav-layer[data-nav-layer="index"] .nav-layer-choice:nth-child(2) { grid-column:3; grid-row:1; }
#scene .ark-header .nav-layer[data-nav-layer="index"] .nav-layer-choice:nth-child(3) { grid-column:3; grid-row:2; }
#scene .ark-header .nav-layer[data-nav-layer="index"] .nav-layer-choice:nth-child(4) { grid-column:1/4; grid-row:3; }
#scene .ark-header .nav-layer[data-nav-layer="index"] .nav-layer-choice:nth-child(5) { grid-column:3; grid-row:3; }
#scene .ark-header .nav-choice-title {
 margin-top:auto; max-width:100%; font:600 16px/1.12 "Albert Sans",sans-serif;
 letter-spacing:-.035em; overflow-wrap:anywhere;
}
#scene .ark-header .nav-layer[data-nav-layer="index"] .nav-layer-choice:first-child .nav-choice-title { font-size:clamp(23px,3cqw,31px); }
#scene .ark-header .nav-choice-description {
 margin-top:6px; max-width:27ch; color:hsl(var(--text-muted));
 font:400 11px/1.3 "Albert Sans",sans-serif;
}
#scene .ark-header .nav-choice-count {
 order:-1; color:hsl(var(--primary)); white-space:nowrap;
 font:600 9px/1.3 var(--mono-font,ui-monospace,monospace);
}
#scene .ark-header .nav-layer-choice::after {
 content:"↗"; position:absolute; top:11px; right:14px;
 color:hsl(var(--primary)); font:400 17px/1 "Albert Sans",sans-serif;
}
#scene .ark-header .nav-layer-body .nav-route-link {
 display:flex; flex-direction:column; align-items:flex-start; justify-content:flex-end;
 min-width:0; min-height:104px; padding:42px 15px 15px; border:1px solid hsl(var(--border-default));
 border-radius:var(--size-card-radius,8px);
 background:linear-gradient(145deg,hsl(var(--raised) / .52),hsl(var(--surface) / .34));
 color:hsl(var(--text-strong)); font:600 15px/1.16 "Albert Sans",sans-serif;
 text-transform:none; letter-spacing:0; white-space:normal;
 box-shadow:inset 0 1px hsl(var(--text-strong) / .035);
 transition:border-color 180ms ease,background-color 180ms ease,transform 180ms ease;
}
#scene .ark-header .nav-layer-body .nav-route-link:is(:hover,[aria-current="page"]) {
 border-color:hsl(var(--primary) / .55); background:hsl(var(--primary) / .1);
 transform:translateY(-2px);
}
#scene .ark-header .nav-layer-body .nav-route-link .ark-link-label {
 display:block; width:100%; min-width:0; overflow-wrap:anywhere; white-space:normal;
}
#scene .ark-header .nav-layer-body .nav-route-link::before {
 position:absolute; top:14px; left:15px;
 color:hsl(var(--primary)); font:500 9px/1 var(--mono-font,ui-monospace,monospace);
}
#scene .ark-header .nav-layer-body .nav-route-link::after {
 position:absolute; top:10px; right:13px; left:auto; bottom:auto;
 width:auto; height:auto; margin:0; background:none; transform:none;
 font-size:15px;
}
#scene .ark-header .nav-layer[data-nav-layer="understand"] .nav-route-link:first-child,
#scene .ark-header .nav-layer[data-nav-layer="evaluate"] .nav-route-link:first-child,
#scene .ark-header .nav-layer[data-nav-layer="run"] .nav-route-link:first-child { grid-column:span 2; border-color:hsl(var(--primary) / .32); }
#scene .ark-header .nav-layer[data-nav-layer="understand"] .nav-route-link:last-child,
#scene .ark-header .nav-layer[data-nav-layer="evaluate"] .nav-route-link:last-child,
#scene .ark-header .nav-layer[data-nav-layer="run"] .nav-route-link:last-child { grid-column:span 2; }
#scene .ark-header .nav-layer[data-nav-layer="read"] .nav-layer-body { grid-template-columns:repeat(2,minmax(0,1fr)); }
#scene .ark-header .nav-layer[data-nav-layer="read"] .nav-route-link:first-child { grid-column:1/-1; }
#scene .ark-header .nav-layer[data-nav-layer="lifecycle"] .nav-layer-body {
 grid-template-columns:repeat(3,minmax(0,1fr)); grid-template-rows:minmax(190px,1fr);
}
#scene .ark-header .nav-layer[data-nav-layer="lifecycle"] .nav-route-link { grid-column:span 2; }
#scene .ark-header .nav-layer[data-nav-layer="lifecycle"] .nav-route-link { border-color:hsl(var(--primary) / .35); font-size:22px; }
#scene .ark-header .nav-layer[data-nav-layer="lifecycle"] .nav-layer-choice { border-color:hsl(var(--primary) / .3); }
#scene .ark-header .nav-layer[data-nav-layer="lifecycle"] .nav-choice-title { font-size:22px; }
#scene .ark-header .nav-layer[data-nav-layer="stages"] .nav-layer-body { grid-template-columns:repeat(3,minmax(0,1fr)); }
#scene .ark-header .nav-layer[data-nav-layer="stages"] .nav-route-link:first-child { grid-column:span 2; }
@keyframes nav-layer-forward-out { to { opacity:0; transform:translateX(-22px); } }
@keyframes nav-layer-forward-in { from { opacity:0; transform:translateX(22px); } }
@keyframes nav-layer-back-out { to { opacity:0; transform:translateX(22px); } }
@keyframes nav-layer-back-in { from { opacity:0; transform:translateX(-22px); } }
#scene .ark-header .nav-layer-out-forward { pointer-events:none; animation:nav-layer-forward-out 150ms ease both; }
#scene .ark-header .nav-layer-in-forward { animation:nav-layer-forward-in 170ms ease both; }
#scene .ark-header .nav-layer-out-back { pointer-events:none; animation:nav-layer-back-out 150ms ease both; }
#scene .ark-header .nav-layer-in-back { animation:nav-layer-back-in 170ms ease both; }
@media(max-width:620px) {
 #scene .ark-header .nav-layer { padding:17px 17px 21px; }
 #scene .ark-header .nav-layer-title { font-size:29px; }
 #scene .ark-header .nav-layer[data-nav-layer="index"] .nav-layer-body {
  grid-template-columns:repeat(2,minmax(0,1fr)); grid-template-rows:repeat(3,minmax(90px,1fr));
 }
 #scene .ark-header .nav-layer[data-nav-layer="index"] .nav-layer-choice:first-child {
  grid-column:1/-1; grid-row:1;
 }
 #scene .ark-header .nav-layer[data-nav-layer="index"] .nav-layer-choice:nth-child(2) { grid-column:1; grid-row:2; }
 #scene .ark-header .nav-layer[data-nav-layer="index"] .nav-layer-choice:nth-child(3) { grid-column:2; grid-row:2; }
 #scene .ark-header .nav-layer[data-nav-layer="index"] .nav-layer-choice:nth-child(4) { grid-column:1/-1; grid-row:3; }
 #scene .ark-header .nav-layer[data-nav-layer="index"] .nav-layer-choice:nth-child(5) { grid-column:2; grid-row:3; }
 #scene .ark-header .nav-layer[data-nav-layer="index"] .nav-layer-choice:not(:first-child) .nav-choice-description { display:none; }
 #scene .ark-header .nav-layer[data-nav-layer="index"] .nav-layer-choice:first-child .nav-choice-title { font-size:21px; }
 #scene .ark-header .nav-layer-body { grid-template-columns:repeat(2,minmax(0,1fr)); grid-template-rows:none; grid-auto-rows:minmax(104px,auto); }
 #scene .ark-header .nav-layer[data-nav-layer="understand"] .nav-route-link:first-child,
 #scene .ark-header .nav-layer[data-nav-layer="evaluate"] .nav-route-link:first-child,
 #scene .ark-header .nav-layer[data-nav-layer="run"] .nav-route-link:first-child,
 #scene .ark-header .nav-layer[data-nav-layer="understand"] .nav-route-link:last-child,
 #scene .ark-header .nav-layer[data-nav-layer="evaluate"] .nav-route-link:last-child,
 #scene .ark-header .nav-layer[data-nav-layer="run"] .nav-route-link:last-child { grid-column:auto; }
 #scene .ark-header .nav-layer-body .nav-route-link { padding:40px 12px 14px; font-size:14px; }
 #scene .ark-header .nav-layer[data-nav-layer="read"] .nav-layer-body { grid-template-rows:none; grid-auto-rows:minmax(120px,auto); }
 #scene .ark-header .nav-layer[data-nav-layer="lifecycle"] .nav-layer-body {
  grid-template-columns:1fr; grid-template-rows:none; grid-auto-rows:minmax(120px,auto);
 }
 #scene .ark-header .nav-layer[data-nav-layer="lifecycle"] .nav-route-link { grid-column:1; }
 #scene .ark-header .nav-layer[data-nav-layer="stages"] .nav-layer-body {
  grid-template-columns:repeat(2,minmax(0,1fr)); grid-template-rows:repeat(3,minmax(90px,1fr));
 }
 #scene .ark-header .nav-layer[data-nav-layer="stages"] .nav-route-link:first-child { grid-column:1/-1; }
}
@media(prefers-reduced-motion:reduce) {
 #scene .ark-header .nav-layer { animation:none !important; }
 #scene .ark-header .nav-layer-choice,
 #scene .ark-header .nav-layer-body .nav-route-link { transition:none; transform:none !important; }
}

/* One corner: stacked destinations at home, a return control on inner pages. */
.corner-navigation,.hero-motion-toggle { right:max(20px,2.8cqmin); bottom:max(14px,2cqmin); }
.corner-navigation { position:absolute; z-index:6; display:flex; flex-direction:column; align-items:flex-end; gap:0; background:none; border:0; }
.corner-navigation[hidden] { display:none; }
.corner-navigation a { display:flex; align-items:center; min-height:44px; padding:8px 4px; color:hsl(var(--text-muted)); font:500 10px var(--ark-font); letter-spacing:.1em; text-transform:uppercase; text-decoration:none; }
.corner-navigation a:hover { color:hsl(var(--text-strong)); }
@media(max-width:760px) { .hero-alive[data-page="zero"] .ark-hero-body { bottom:165px !important; } }
@media(max-width:480px) { .ark-studio-label { max-width:85px; line-height:1.5; } }

/* A quiet invitation in the shared layout, without a card surface. */
.theory-invitation { position:absolute; top:112px; right:max(24px,3cqw); z-index:5; width:220px; padding:8px 0; display:grid; gap:12px; border:0; background:none; box-shadow:none; color:hsl(var(--text)); text-decoration:none; }
.theory-invitation[hidden] { display:none; }
.theory-invitation-label { color:hsl(var(--text-muted)); font:400 10px/1.5 var(--ark-font); letter-spacing:.035em; }
.theory-invitation strong { font:300 24px/1.18 var(--ark-font); letter-spacing:-.035em; }
.theory-invitation-link { margin-top:4px; color:hsl(var(--text-muted)); font:400 11px/1.5 var(--ark-font); transition:color 180ms ease; }
.theory-invitation:hover .theory-invitation-link { color:hsl(var(--text-strong)); }
#scene .theory-invitation:focus-visible { background:none; color:hsl(var(--text-strong)); }
.theory-invitation:focus-visible .theory-invitation-link { text-decoration:underline; text-underline-offset:5px; }
@media(max-width:760px) { .theory-invitation { top:94px; right:20px; width:175px; gap:9px; } .theory-invitation strong { font-size:21px; } }
@media(prefers-reduced-motion:reduce) { .theory-invitation-link { transition:none; } }

/* Identity is a live navigation destination, with status independent of route. */
.header-account-label{display:flex;flex-direction:column;align-items:flex-start;gap:3px;min-width:0}
.header-account-name{max-width:120px;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.header-account-status{display:flex;align-items:center;gap:4px;font:500 8px/1 var(--mono-font,monospace);color:hsl(var(--text-muted))}
.header-account-status:before{content:"";height:4px;width:4px;border-radius:50%;background:currentColor}
.header-account-link[data-signed-in="true"] .header-account-status{color:hsl(var(--trust,var(--primary)))}
@media(max-width:560px){
 #scene .ark-header .header-core-links{display:flex;border:0;background:transparent;padding:0;margin-left:auto}
 #scene .ark-header .header-core-links a:not(.header-account-link){display:none}
 #scene .ark-header .header-core-links .header-account-link{display:flex;min-width:100px;font-size:12px;border:1px solid hsl(var(--border-subtle));background:hsl(var(--canvas) / .65)}
}