/* Home page.
   Layout: a night band (header and hero) where a live robot scene sits beside the headline; a scroll story with a
   sticky stage; quiet sections on the site's own tokens; a closing night band.
   The night band is one fixed look in both themes: a robotics mat under low light. Its colors come from the lab:
   the tangerine robot, the star's amber, and the block colors (move blue, loop amber, event mint, look lilac). */
:root{
  --night:#0D2B33;    /* the mat at night */
  --night-2:#123B45;  /* raised surfaces on the night band */
  --chalk:#E8F1EE;    /* text and lines on night */
  --chalk-2:#A9C6C1;  /* quieter text on night */
  --tang:#FA903E;     /* the robot, and the main action */
  --tang-ink:#2A1404; /* text on tangerine */
  --spark:#FCC934;    /* stars, XP, loop blocks */
  --mint:#5ED39B;     /* done, the trail, event blocks */
  --sky:#7BB0FF;      /* move blocks */
  --lilac:#B9A2F0;    /* look blocks */
  --ease-out:cubic-bezier(.23,1,.32,1);
  --ease-io:cubic-bezier(.77,0,.175,1);
}

/* ---------- night band, header and buttons ---------- */
.night{background:var(--night);color:var(--chalk)}
.night a:not(.btn):not(.gbtn){color:var(--chalk)}
.night :focus-visible,.onnight :focus-visible{outline-color:var(--sky)}
.sitehead.onnight{background:var(--night);border-bottom:1px solid rgba(232,241,238,.1)}
.onnight .logo,.onnight .sitenav a:not(.btn){color:var(--chalk)}
.onnight .logo .mark{background:rgba(250,144,62,.14);border-color:rgba(250,144,62,.55);color:var(--tang)}
.btn.tangerine{background:var(--tang);border-color:var(--tang);color:var(--tang-ink)}
.btn.ghostnight{background:transparent;border-color:rgba(232,241,238,.38);color:var(--chalk)}
.home .btn,.home .gbtn{transition:transform 120ms var(--ease-out),background-color .15s ease,border-color .15s ease}
.home .btn:not(:disabled):active,.home .gbtn:active{transform:scale(.97)}
@media (hover:hover) and (pointer:fine){
  .btn.tangerine:hover{background:#FFA45E;border-color:#FFA45E}
  .btn.ghostnight:hover{border-color:var(--chalk)}
}
.night .gbtn{--g-bg:#FFFFFF;--g-line:#747775;--g-ink:#1F1F1F}

/* ---------- hero ---------- */
.home .hero{display:block;position:relative;isolation:isolate;overflow:hidden;padding-block:clamp(24px,4.5vw,56px) 24px}
.hero::before{content:"";position:absolute;inset:0;z-index:-1;pointer-events:none;
  background-image:radial-gradient(rgba(232,241,238,.07) 1.2px,transparent 1.5px);background-size:28px 28px;
  -webkit-mask-image:linear-gradient(#000 30%,transparent 95%);mask-image:linear-gradient(#000 30%,transparent 95%)}
.hero-grid{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1.12fr);grid-template-areas:"copy scene" "box scene";column-gap:clamp(16px,4vw,48px);row-gap:28px;align-items:start}
.hero-copy{grid-area:copy;align-self:end;min-width:0}
.hero-scene{grid-area:scene;align-self:center;position:relative;min-width:0}
.grownbox{grid-area:box;min-width:0}
.hero h1{font-size:clamp(2.35rem,5vw,4.25rem);line-height:1.06;letter-spacing:-.03em;font-weight:700;margin:0 0 20px;color:var(--chalk)}
.h1v,.h1b{display:block}
.h1top{display:block;white-space:nowrap}
.pill{display:inline-block;position:relative;padding:0 .26em .04em;border-radius:.2em;background:var(--pc,var(--chalk));color:var(--night);transform-origin:15% 70%;white-space:nowrap}
.pill::before{content:"";position:absolute;left:.4em;top:-.1em;width:.6em;height:.14em;border-radius:.07em .07em 0 0;background:inherit}
.home .hero p.lead{font-size:clamp(1.05rem,1.35vw,1.2rem);line-height:1.6;color:var(--chalk-2);max-width:44ch;margin:0 0 26px}
.try{display:flex;flex-wrap:wrap;align-items:center;gap:10px 18px}
.try .btn{min-height:58px;padding-inline:28px;font-size:1.12rem}
.try .btn svg{width:18px;height:18px}
.try .note{margin:0;color:var(--chalk-2);font-size:.95rem}
.grownbox{max-width:460px;padding:18px;border-radius:20px;background:rgba(232,241,238,.05);border:1px solid rgba(232,241,238,.13)}
.gb-t{margin:0 0 12px;font-weight:600}
.gb-row{display:grid;gap:10px}
.gb-row .btn,.gb-row .gbtn{width:100%;min-height:52px}
.gb-kid{margin:12px 0 0;font-size:.95rem;color:var(--chalk-2)}
.motionbtn{position:absolute;right:6px;bottom:6px;z-index:8;display:inline-flex;align-items:center;gap:8px;min-height:44px;padding:6px 16px 6px 12px;border-radius:999px;border:1px solid rgba(232,241,238,.3);background:rgba(13,43,51,.86);color:var(--chalk);font:600 .92rem var(--font-ui);cursor:pointer}
.motionbtn svg{width:18px;height:18px;flex:none}
.motionbtn .i-play,.motion-off .motionbtn .i-pause{display:none}
.motion-off .motionbtn .i-play{display:inline}
@media (hover:hover) and (pointer:fine){.motionbtn:hover{border-color:var(--chalk)}}
.facts{list-style:none;margin:36px auto 0;padding-block:20px 6px;display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:14px;border-top:1px solid rgba(232,241,238,.1)}
.facts li{display:flex;gap:10px;align-items:center;color:var(--chalk-2);font-size:.98rem;min-width:0}
.facts svg{width:22px;height:22px;color:var(--tang);flex:none}
.facts b{color:var(--chalk);font-weight:600}
.facts a{text-decoration-color:rgba(232,241,238,.35)}
@media (max-width:920px){
  .hero-grid{grid-template-columns:minmax(0,1fr);grid-template-areas:"copy" "scene" "box";row-gap:18px}
  .hero-copy{align-self:start}
  .grownbox{max-width:none}
}
@media (max-width:760px){.facts{grid-template-columns:repeat(2,minmax(0,1fr))}}
@media (max-width:640px){.sitenav .navx{display:none}}
@media (max-width:559px){.motionbtn{top:4px;bottom:auto;right:4px}}
@media (max-width:520px){
  .hero h1{font-size:clamp(1.9rem,8.4vw,2.6rem)}
  .try .btn{width:100%}
}

/* ---------- scenes: a fixed-size stage scaled to fit its box ---------- */
.scene{position:relative;width:100%;aspect-ratio:var(--ar,640/560)}
.scene .poster{position:absolute;inset:0;width:100%;height:100%}
.hero-scene::before{content:"";position:absolute;inset:4% 2% 8%;z-index:0;pointer-events:none;background:radial-gradient(closest-side,rgba(250,144,62,.2),rgba(250,144,62,0))}
.stage{position:absolute;left:0;top:0;transform-origin:0 0;z-index:1}
.mat{position:absolute;left:0;top:0;overflow:visible}
.m-top{fill:#14434F}
.m-sl{fill:#0A2229}
.m-sr{fill:#0C2830}
.m-edge{fill:none;stroke:rgba(232,241,238,.28);stroke-width:1.6;stroke-linejoin:round}
.m-grid line{stroke:rgba(232,241,238,.13);stroke-width:1.2}
.m-dots circle{fill:rgba(232,241,238,.24)}
.m-tile{fill:var(--mint);fill-opacity:0;transition:fill-opacity .35s ease}
.m-tile.lit{fill-opacity:.26}
.m-start{fill:none;stroke:rgba(94,211,155,.6);stroke-width:1.6;stroke-dasharray:5 4}
.actor{position:absolute;left:0;top:0}
.r-shadow{position:absolute;left:-26px;top:-5px;width:52px;height:18px;border-radius:50%;background:radial-gradient(closest-side,rgba(0,0,0,.45),rgba(0,0,0,0))}
.r-hop,.r-squash,.r-face{position:absolute;left:0;top:0;transform-origin:0 0}
.rb{position:absolute;left:-36px;top:-74px;width:72px;height:90px;overflow:visible}
.r-eyes{transform-box:fill-box;transform-origin:center}
.star .s-halo{position:absolute;left:-25px;top:-12px;width:50px;height:24px;border-radius:50%;border:2px solid rgba(252,201,52,.55);box-shadow:0 0 0 5px rgba(252,201,52,.1)}
.star .s-bob{position:absolute;left:0;top:0;animation:ndbob 2.4s var(--ease-io) infinite alternate}
.star svg{position:absolute;left:-17px;top:-50px;width:34px;height:34px}
.rock svg{position:absolute;left:-24px;top:-25px;width:48px;height:34px}
/* the hero's mat has bigger squares, so its robot, star and rocks are drawn a size up */
.big .rb{left:-45px;top:-92.5px;width:90px;height:112.5px}
.big .r-shadow{left:-32px;top:-7px;width:64px;height:22px}
.big .star svg{left:-21px;top:-60px;width:42px;height:42px}
.big .star .s-halo{left:-31px;top:-15px;width:62px;height:30px}
.big .rock svg{left:-30px;top:-31px;width:60px;height:42px}
@keyframes ndbob{from{transform:translateY(-3px)}to{transform:translateY(3px)}}
.badge{position:absolute;width:58px;height:58px;border-radius:17px;display:grid;place-items:center;color:var(--night);box-shadow:0 12px 26px rgba(0,0,0,.3);animation:ndfloat var(--d,6s) var(--ease-io) infinite alternate;animation-delay:var(--dl,0s)}
.badge svg{width:30px;height:30px}
@keyframes ndfloat{from{transform:translateY(-6px) rotate(var(--r0,-6deg))}to{transform:translateY(6px) rotate(var(--r1,-2deg))}}
.spark{position:absolute;left:-4px;top:-4px;width:9px;height:9px;border-radius:3px;pointer-events:none}
.xp{position:absolute;left:0;top:0;pointer-events:none;z-index:60}
.xp span{display:block;transform:translateX(-50%);padding:4px 11px;border-radius:999px;background:var(--spark);color:var(--night);font:700 15px/1.2 var(--font-ui);white-space:nowrap;box-shadow:0 6px 16px rgba(0,0,0,.25)}
.bang{position:absolute;left:0;top:0;z-index:60;opacity:0;pointer-events:none}
.bang span{display:grid;place-items:center;transform:translate(-50%,-100%);width:30px;height:30px;border-radius:10px;background:var(--spark);color:var(--night);font:800 19px/1 var(--font-ui)}

/* the code card inside a scene */
.codecard{position:absolute;padding:12px;border-radius:16px;background:rgba(18,59,69,.92);border:1px solid rgba(232,241,238,.14);box-shadow:0 18px 40px rgba(0,0,0,.35);color:var(--chalk);font:600 14px/1.25 var(--font-ui);z-index:40}
.cc-head{display:flex;align-items:center;gap:8px;margin:0 0 10px;font-size:13px;color:var(--chalk-2);min-height:20px}
.cc-lv{padding:2px 7px;border-radius:7px;background:rgba(232,241,238,.12);color:var(--chalk);font-variant-numeric:tabular-nums}
.cc-hat{display:flex;align-items:center;gap:7px;padding:8px 10px;border-radius:11px 11px 11px 4px;background:var(--mint);color:var(--night);font-size:13px;white-space:nowrap}
.cc-hat svg,.cblk svg,.cc-run svg{width:15px;height:15px;flex:none}
.cc-list{position:relative;margin-top:6px;padding-left:10px;display:flex;flex-direction:column;gap:6px;min-height:34px}
.cblk{position:relative;z-index:1;display:flex;align-items:center;gap:7px;height:34px;padding:0 10px;border-radius:9px;color:var(--night);white-space:nowrap}
.cblk.m,.cblk.t{background:var(--sky)}
.cblk.c{background:var(--spark)}
.cblk.in{margin-left:16px}
.cblk .num{display:inline-block;min-width:.7em;text-align:center;border-radius:5px;padding:0 3px;background:rgba(13,43,51,.14);font-variant-numeric:tabular-nums}
.cblk .num.fixed{background:var(--mint)}
.band{position:absolute;left:4px;right:-6px;top:0;height:42px;border-radius:12px;border:2px solid var(--chalk);box-shadow:0 0 0 4px rgba(232,241,238,.12),0 0 18px rgba(232,241,238,.22);opacity:0;pointer-events:none;z-index:2;transition:transform 220ms var(--ease-io),opacity 160ms ease}
.cc-foot{margin-top:12px;display:flex;justify-content:flex-end}
.codecard.compact{padding:10px}
.compact .cc-head{margin-bottom:8px}
.compact .cc-hat{padding:6px 9px}
.compact .cc-list{gap:4px}
.compact .cblk{height:30px}
.compact .cc-foot{margin-top:8px}
.cc-run{display:inline-flex;align-items:center;gap:6px;padding:7px 12px;border-radius:10px;background:var(--mint);color:var(--night);font-size:13px}
.minipath{position:absolute;display:flex;align-items:center;transform:translateX(-50%);z-index:40}
.mp-node{position:relative;width:46px;height:46px;border-radius:50%;display:grid;place-items:center;font:700 13px var(--font-ui);color:var(--chalk-2);background:var(--night-2);border:2px solid rgba(232,241,238,.2);font-variant-numeric:tabular-nums}
.mp-node svg{width:20px;height:20px}
.mp-node.cur{color:var(--chalk);border-color:var(--tang)}
.mp-node.cur::after{content:"";position:absolute;inset:-7px;border-radius:50%;border:2px solid var(--tang);animation:ndring 1.8s var(--ease-out) infinite}
.mp-node.done{background:var(--mint);border-color:var(--mint);color:var(--night)}
.mp-link{width:40px;height:3px;background:repeating-linear-gradient(90deg,rgba(232,241,238,.3) 0 6px,transparent 6px 11px)}
@keyframes ndring{from{transform:scale(.86);opacity:.7}to{transform:scale(1.22);opacity:0}}
.fixcard{position:absolute;z-index:50;padding:14px 16px;border-radius:16px;background:#F4F8F5;color:#16323A;box-shadow:0 18px 40px rgba(0,0,0,.35);font:500 15px/1.4 var(--font-ui);opacity:0}
.fixcard p{margin:0}
.fixcard .ok{display:flex;gap:8px;align-items:center;font-weight:600}
.fixcard .ok svg{width:18px;height:18px;color:#1E8E3E;flex:none}
.fixcard .diff{margin:9px 0;padding:8px 11px;border-radius:10px;background:#FFF1DA;border:1.5px solid #E2A13F}
.fixcard .diff s{color:#8A4B0F}
.fixcard .diff b{background:#BDEBD2;border-radius:4px;padding:0 4px}
.fixcard .fixbtn{display:inline-flex;align-items:center;min-height:32px;padding:4px 12px;border-radius:9px;background:#16323A;color:#F4F8F5;font-weight:600;font-size:13px;transform-origin:center}
.calmsw{position:absolute;z-index:50;display:flex;align-items:center;gap:10px;padding:7px 12px 7px 9px;border-radius:999px;background:rgba(232,241,238,.12);color:var(--chalk);font:600 14px var(--font-ui)}
.calmsw .sw{position:relative;width:44px;height:26px;border-radius:999px;background:rgba(232,241,238,.28);transition:background-color .3s ease}
.calmsw .sw i{position:absolute;left:3px;top:3px;width:20px;height:20px;border-radius:50%;background:var(--chalk)}
.calmsw.on .sw{background:var(--mint)}
.flood{position:absolute;inset:0;z-index:0;overflow:hidden;border-radius:inherit}
.flood i{position:absolute;inset:0}
.story-scene .stage{transition:filter .6s ease}
.story-scene.calm .stage{filter:saturate(.4) brightness(.96)}

/* motion stops: the Pause button, calm mode, off screen */
.motion-off .badge,.motion-off .s-bob,.motion-off .mp-node.cur::after,.idle .badge,.idle .s-bob,.idle .mp-node.cur::after{animation-play-state:paused}

/* ---------- the scroll story ---------- */
.story{padding-block:clamp(52px,7vw,96px) 20px}
.story-head{max-width:38rem;margin-bottom:8px}
.story-head h2{font-size:clamp(1.8rem,3.6vw,2.7rem);letter-spacing:-.025em;margin-bottom:10px}
.story-head p{color:var(--muted);font-size:1.12rem;margin:0}
.story-body{display:grid;grid-template-columns:minmax(0,5fr) minmax(0,7fr);column-gap:clamp(20px,4vw,56px);align-items:start}
.story-stage{grid-column:2;grid-row:1;position:sticky;top:max(16px,calc(50vh - 240px))}
.story-stage .scene{--ar:640/460;border-radius:28px;overflow:hidden;background:var(--night);box-shadow:var(--shadow)}
.story-steps{grid-column:1;grid-row:1;list-style:none;margin:0;padding:0}
.chap{min-height:78vh;display:flex;flex-direction:column;justify-content:center;max-width:30rem;color:var(--muted)}
.chap h3{color:var(--muted);transition:color .3s ease}
.chap.on h3{color:var(--ink)}
.chap-n{display:grid;place-items:center;width:42px;height:42px;border-radius:13px;background:var(--surface-2);border:1px solid var(--line);font-weight:700;margin-bottom:14px;font-variant-numeric:tabular-nums;transition:background-color .3s ease,color .3s ease,border-color .3s ease}
.chap.on .chap-n{background:var(--tang);border-color:var(--tang);color:var(--tang-ink)}
.chap h3{font-size:clamp(1.4rem,2.4vw,1.85rem);letter-spacing:-.015em;margin-bottom:10px}
.chap p{font-size:1.12rem;line-height:1.6;color:var(--muted);margin:0}
.js-story .chap:first-child{margin-top:-10vh}
@media (max-width:900px){
  .story-body{grid-template-columns:minmax(0,1fr)}
  .story-stage{grid-column:1;grid-row:1;top:calc(env(safe-area-inset-top,0px) + 8px);z-index:2;padding-bottom:12px;background:var(--bg)}
  .story-stage::after{content:"";position:absolute;left:0;right:0;bottom:-28px;height:28px;background:linear-gradient(var(--bg),transparent);pointer-events:none}
  .story-steps{grid-column:1;grid-row:1;padding-top:calc(var(--stage-h,70vw) + 24px)}
  .chap{min-height:calc(100vh - var(--stage-h,70vw) - 32px);justify-content:center;padding-block:16px;max-width:none}
  .js-story .chap:first-child{margin-top:0}
}
/* With motion off, the story is four still frames, one per step, so nothing slides while you scroll. */
.motion-off .story-scene *,.motion-off .chap,.motion-off .chap-n{transition:none!important}

/* ---------- the same program, four ways ---------- */
.ladsec{display:grid;grid-template-columns:minmax(0,4fr) minmax(0,6fr);gap:clamp(18px,4vw,48px);align-items:center;padding-top:56px}
.ladcopy h2{font-size:clamp(1.5rem,2.8vw,2.1rem);letter-spacing:-.02em}
.lad{background:var(--night);color:var(--chalk);border-radius:24px;padding:18px;min-width:0}
.ladtabs{display:flex;flex-wrap:wrap;gap:4px;padding:4px;border-radius:14px;background:rgba(232,241,238,.07);margin-bottom:16px}
.ladtabs button{flex:1 1 auto;min-height:44px;border:0;border-radius:10px;background:transparent;color:var(--chalk-2);font:600 1rem var(--font-ui);cursor:pointer;padding:6px 12px}
.ladtabs button[aria-selected="true"]{background:var(--chalk);color:var(--night)}
.ladpanel{min-height:184px;padding:4px}
.ladpanel:focus-visible{outline-offset:4px}
.ladpanel pre{margin:0;font:600 1.12rem/1.8 var(--font-code);white-space:pre;overflow-x:auto;color:var(--chalk)}
.ladpanel .ln{display:block}
.ladpanel .k{color:var(--tang)}
.ladpanel .n{color:var(--spark)}
.lb{display:flex;align-items:center;gap:9px;width:max-content;max-width:100%;padding:9px 14px;border-radius:11px;font-weight:600;color:var(--night);margin-bottom:6px}
.lb svg{width:18px;height:18px;flex:none}
.lb.hat{background:var(--mint);border-radius:14px 14px 14px 5px}
.lb.ctl{background:var(--spark)}
.lb.mot{background:var(--sky)}
.lb.in{margin-left:26px}
.ladnote{margin:12px 0 0;color:var(--chalk-2);font-size:.95rem}
@media (max-width:860px){.ladsec{grid-template-columns:minmax(0,1fr)}}

/* ---------- research, supports, grown-ups ---------- */
.home .section>p.sub{max-width:62ch;margin-bottom:20px}
.home .section>h2{font-size:clamp(1.5rem,2.8vw,2.1rem);letter-spacing:-.02em}
.research .finding{border-top:1px solid var(--line);position:relative;padding-top:24px}
.research .finding::before{content:"";position:absolute;left:18px;top:-1px;width:58px;height:9px;border-radius:0 0 7px 7px;background:var(--tabe)}
.count{font-variant-numeric:tabular-nums}
.trycard{display:grid;gap:16px;padding:22px;border-radius:22px;background:var(--surface);border:1px solid var(--line);margin-bottom:14px}
.sample{margin:0;font-size:1.35rem;line-height:1.6;font-weight:500;min-height:3.3em}
.sample[data-font="atkinson"]{font-family:"Atkinson Hyperlegible",Verdana,sans-serif}
.sample[data-font="dyslexic"]{font-family:"OpenDyslexic",Verdana,sans-serif;word-spacing:.12em}
.sample[data-size="l"]{font-size:1.65rem}
.sample[data-size="xl"]{font-size:2rem}
.trycontrols{display:flex;flex-wrap:wrap;gap:10px 14px;align-items:center}
#sizeSeg button[data-size="m"]{font-size:.92rem}
#sizeSeg button[data-size="l"]{font-size:1.08rem}
#sizeSeg button[data-size="xl"]{font-size:1.28rem}
.calmrow{display:inline-flex;align-items:center;gap:10px;font-weight:600;cursor:pointer}
.who3{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));border:1px solid var(--line);border-radius:20px;background:var(--surface);margin-bottom:14px}
.whoc{padding:20px 22px;min-width:0}
.whoc+.whoc{border-left:1px solid var(--line)}
.whoc h3{margin-bottom:6px}
.whoc p{margin:0;color:var(--muted)}
@media (max-width:760px){.who3{grid-template-columns:minmax(0,1fr)}.whoc+.whoc{border-left:0;border-top:1px solid var(--line)}}
.signrow{display:flex;flex-wrap:wrap;gap:10px;margin-top:20px;align-items:center}
.signrow .gbtn{width:auto;min-height:56px;padding-inline:22px}

/* ---------- closing band ---------- */
.finale{margin-top:64px;padding-block:clamp(40px,6vw,72px)}
.finale-in{display:grid;grid-template-columns:auto minmax(0,1fr);gap:clamp(16px,4vw,48px);align-items:center}
.finale-bot{position:relative;width:170px;height:170px}
.finale h2{font-size:clamp(1.8rem,3.6vw,2.8rem);letter-spacing:-.025em;color:var(--chalk);margin-bottom:8px}
.finale p{color:var(--chalk-2);font-size:1.12rem}
.finale .btn svg{width:18px;height:18px}
.home .sitefoot{margin-top:0}
@media (max-width:640px){.finale-in{grid-template-columns:minmax(0,1fr)}.finale-bot{width:140px;height:140px}}