/* Function Machines — styles. Colour tokens first; everything else uses them. */
/* Layout: one column, max 960px. The hero is a three-lane conveyor (formula in | machine | formula out)
   that stays horizontal at every width and scales with the viewport; everything else is quiet panels. */
:root{
  --bg:#edf0f3; --panel:#ffffff; --panel-2:#f4f6f8; --ink:#1a222c; --muted:#5b6878; --line:#cfd7df;
  --steel:#4a5b6e; --steel-light:#6e8197; --steel-dark:#2a3542; --brass:#b9872a;
  --amber:#f2a416; --amber-ink:#6b4300; --amber-soft:#fff0d2;
  --ok:#1f8f5f; --ok-soft:#dcf4e8; --bad:#cf4b45; --bad-soft:#fde3e1;
  --display:#0d1721; --display-text:#8df0a8; --lamp-off:#7a848f; --focus:#2d6cdf;
  --font-display:'Chakra Petch','Trebuchet MS','Arial Narrow',sans-serif;
  --font-body:'Atkinson Hyperlegible','Segoe UI',system-ui,-apple-system,sans-serif;
}
@media (prefers-color-scheme:dark){
  :root:not([data-theme="light"]){
    --bg:#12181f; --panel:#1b232d; --panel-2:#222c38; --ink:#e9eef3; --muted:#a0adbb; --line:#33404e;
    --steel:#3a4858; --steel-light:#55687e; --steel-dark:#1b242e; --brass:#c99a3a;
    --amber:#f5ad2a; --amber-ink:#ffd98a; --amber-soft:#3a2d12;
    --ok:#43c58a; --ok-soft:#173529; --bad:#ef6b64; --bad-soft:#40201f;
    --display:#070d13; --display-text:#8df0a8; --lamp-off:#5a6572; --focus:#7fa6ff;
    color-scheme:dark;
  }
}
:root[data-theme="dark"]{
  --bg:#12181f; --panel:#1b232d; --panel-2:#222c38; --ink:#e9eef3; --muted:#a0adbb; --line:#33404e;
  --steel:#3a4858; --steel-light:#55687e; --steel-dark:#1b242e; --brass:#c99a3a;
  --amber:#f5ad2a; --amber-ink:#ffd98a; --amber-soft:#3a2d12;
  --ok:#43c58a; --ok-soft:#173529; --bad:#ef6b64; --bad-soft:#40201f;
  --display:#070d13; --display-text:#8df0a8; --lamp-off:#5a6572; --focus:#7fa6ff;
  color-scheme:dark;
}
html{height:100%}
*{box-sizing:border-box}
.mini .av{width:100%;height:100%}
.footer{margin-top:40px;padding-top:14px;border-top:2px solid var(--line);color:var(--muted);font-size:.9rem;display:flex;gap:12px;flex-wrap:wrap;justify-content:space-between}
.footer a{color:var(--muted)}
.pulse{animation:pulse .5s ease-out 1}
@keyframes pulse{30%{transform:scale(1.25)}}
[hidden]{display:none!important}
body{margin:0;background:var(--bg);color:var(--ink);font-family:var(--font-body);font-size:17px;line-height:1.5;-webkit-font-smoothing:antialiased}
.wrap{max-width:960px;margin:0 auto;padding-inline:16px;padding-block:0 56px}
h1,h2,h3{font-family:var(--font-display);line-height:1.15;text-wrap:balance;margin:0;font-weight:700}
h1{font-size:clamp(1.7rem,4.5vw,2.5rem)}
h2{font-size:clamp(1.3rem,3.2vw,1.7rem)}
p{margin:0}
button,input,select{font:inherit}
.sr-only{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap}
.muted{color:var(--muted)}
.small{font-size:.95rem}
.eyebrow{font-family:var(--font-display);font-size:.8rem;letter-spacing:.1em;text-transform:uppercase;color:var(--muted)}
i{font-style:italic}
sup{font-size:.62em;vertical-align:.55em;line-height:0}
.formula{font-weight:700;white-space:nowrap;font-variant-numeric:tabular-nums}

/* header */
.top{display:flex;align-items:center;justify-content:space-between;gap:10px 16px;flex-wrap:wrap;padding-block:14px;border-bottom:2px solid var(--line)}
.brand{display:flex;align-items:center;gap:10px;font-family:var(--font-display);font-weight:700;font-size:1.25rem}
.brand svg{width:30px;height:30px;color:var(--amber)}
.brand svg path{fill:currentColor;fill-rule:evenodd;transform-box:fill-box;transform-origin:center;animation:spin 14s linear infinite}
.nav{display:flex;gap:4px;flex-wrap:wrap;align-items:center}
.nav button{background:none;border:0;padding:8px 12px;border-radius:8px;color:var(--muted);font-weight:700;cursor:pointer;min-height:40px}
.nav button:hover{color:var(--ink)}
.nav button.active{background:var(--panel);color:var(--ink);box-shadow:inset 0 0 0 2px var(--line)}
.nav button:focus-visible,.chips button:focus-visible,input:focus-visible,select:focus-visible{outline:3px solid var(--focus);outline-offset:2px}
.nav .chip{display:inline-flex;align-items:center;gap:8px;border:2px solid var(--line)!important;border-radius:999px;color:var(--ink)!important;padding:6px 12px 6px 8px}
.nav .chip .dotc{width:18px;height:18px;border-radius:50%;background:var(--amber);display:inline-block}

/* buttons */
.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;min-height:44px;padding:8px 18px;border-radius:10px;border:2px solid var(--line);background:var(--panel);color:var(--ink);font-weight:700;cursor:pointer;font-family:var(--font-display);letter-spacing:.02em;font-size:1rem;text-decoration:none}
.btn:hover{border-color:var(--muted)}
.btn:focus-visible{outline:3px solid var(--focus);outline-offset:2px}
.btn.primary{background:var(--amber);border-color:var(--amber);color:#1b1300}
.btn.primary:hover{filter:brightness(1.06)}
.btn.ghost{background:transparent}
.btn.danger{border-color:var(--bad);color:var(--bad)}
.btn[disabled]{opacity:.5;cursor:not-allowed}
.btn[disabled]:hover{border-color:var(--line)}
.btnrow{display:flex;gap:10px;flex-wrap:wrap;margin-top:16px}

/* panels */
.panel{background:var(--panel);border:2px solid var(--line);border-radius:14px;padding:18px 20px}
.view{padding-block:8px}

/* the machine stage */
.stage{--mw:clamp(108px,26vw,230px);--lane-h:clamp(118px,24vw,172px);font-size:clamp(1.02rem,3.9vw,1.65rem);display:grid;grid-template-columns:1fr var(--mw) 1fr;align-items:center;margin-block:8px;min-width:0}
.lane{position:relative;height:var(--lane-h);display:flex;align-items:center;justify-content:center;min-width:0}
.belt{position:absolute;left:0;right:0;top:calc(50% + 1.45em);height:12px;border-radius:6px;background:repeating-linear-gradient(90deg,var(--steel-dark) 0 10px,var(--steel) 10px 20px);background-size:20px 100%;opacity:.9}
.lane.in .belt{border-radius:6px 0 0 6px}
.lane.out .belt{border-radius:0 6px 6px 0}
.stage.running .belt{animation:belt .55s linear infinite}
@keyframes belt{to{background-position:20px 0}}
.card{position:relative;z-index:2;font-size:1em;font-weight:700;padding:.32em .7em;background:var(--panel);border:2px solid var(--line);border-radius:.45em;box-shadow:0 8px 16px -10px rgba(0,0,0,.45);white-space:normal;text-align:center;line-height:1.3;font-variant-numeric:tabular-nums;will-change:transform;max-width:calc(100% - 6px)}
.card.long{font-size:.82em}
.card.xlong{font-size:.7em}
.card.ghost{color:var(--muted);border-style:dashed;background:transparent;box-shadow:none}
.card.fresh{border-color:var(--ok);box-shadow:0 0 0 4px var(--ok-soft),0 8px 16px -10px rgba(0,0,0,.45)}
.machine{position:relative;width:var(--mw);height:calc(var(--lane-h) + 24px);z-index:3}
.m-hopper{position:absolute;left:30%;right:30%;top:0;height:13%;background:var(--steel-dark);clip-path:polygon(0 0,100% 0,84% 100%,16% 100%)}
.m-body{position:absolute;left:0;right:0;top:12%;bottom:7%;background:linear-gradient(180deg,var(--steel-light),var(--steel) 45%,var(--steel-dark));border:2px solid var(--steel-dark);border-radius:12px;box-shadow:inset 0 2px 0 rgba(255,255,255,.18),0 16px 26px -16px rgba(0,0,0,.65)}
.m-lamp{position:absolute;top:7px;right:9px;width:11px;height:11px;border-radius:50%;background:var(--lamp-off);box-shadow:0 0 0 2px rgba(0,0,0,.3);z-index:2}
.m-lamp.amber{background:var(--amber);box-shadow:0 0 10px 2px var(--amber);animation:blink .3s steps(2) infinite}
.m-lamp.ok{background:var(--ok);box-shadow:0 0 10px 2px var(--ok)}
.m-lamp.bad{background:var(--bad);box-shadow:0 0 10px 2px var(--bad)}
.m-display{position:absolute;left:9%;right:9%;top:13%;height:30%;background:var(--display);color:var(--display-text);border-radius:6px;border:2px solid var(--steel-dark);display:flex;align-items:center;justify-content:center;font-family:var(--font-display);font-weight:700;font-size:.9em;letter-spacing:.03em;box-shadow:inset 0 0 12px rgba(0,0,0,.85);white-space:nowrap;overflow:hidden}
.machine.working .m-display{animation:flash .28s steps(2) infinite}
.machine.jam .m-display{color:var(--bad)}
.m-gears{position:absolute;left:0;right:0;top:48%;bottom:3%;display:flex;align-items:center;justify-content:center;overflow:hidden}
.gear{width:40%;height:auto;flex:none}
.gear.g1{color:var(--steel-dark)}
.gear.g2{color:var(--brass);margin-left:-5%;width:33%}
.gear path{fill:currentColor;fill-rule:evenodd;transform-box:fill-box;transform-origin:center;animation:spin 7s linear infinite}
.gear.g2 path{animation-direction:reverse;animation-duration:5.8s}
.machine.working .gear path{animation-duration:.7s}
.machine.working .gear.g2 path{animation-duration:.58s}
.m-slot{position:absolute;top:50%;width:9px;height:2.3em;transform:translateY(-50%);background:var(--display);border-radius:3px;z-index:2}
.m-slot.left{left:-6px}.m-slot.right{right:-6px}
.m-feet{position:absolute;left:12%;right:12%;bottom:0;height:7%;display:flex;justify-content:space-between}
.m-feet span{width:22%;height:100%;background:var(--steel-dark);border-radius:0 0 4px 4px}
.machine.working{animation:shake .12s linear infinite}
.machine.jam{animation:jolt .5s ease-in-out 1}
@keyframes spin{to{transform:rotate(360deg)}}
@keyframes shake{0%,100%{transform:translate(0,0)}25%{transform:translate(1px,-1px)}75%{transform:translate(-1px,1px)}}
@keyframes jolt{0%,100%{transform:translateX(0)}20%{transform:translateX(-6px)}40%{transform:translateX(6px)}60%{transform:translateX(-4px)}80%{transform:translateX(4px)}}
@keyframes blink{to{opacity:.35}}
@keyframes flash{to{opacity:.55}}
.caption{text-align:center;color:var(--muted);min-height:1.6em;font-variant-numeric:tabular-nums}

/* login */
.hero{display:grid;gap:18px;margin-top:20px}
.lead{max-width:62ch;color:var(--muted);font-size:1.05rem;margin-top:8px}
.login{display:grid;gap:12px;grid-template-columns:1fr 1fr auto;align-items:end;margin-top:12px}
@media (max-width:640px){.login{grid-template-columns:1fr}}
.field{display:flex;flex-direction:column;gap:6px;min-width:0}
.field label{font-weight:700;font-size:.95rem}
.field input,.field select{font-size:1.1rem;padding:10px 12px;border:2px solid var(--line);border-radius:10px;background:var(--panel-2);color:var(--ink);min-width:0;min-height:44px}
.chips{display:flex;gap:8px;flex-wrap:wrap;margin-top:6px}
.chips button{border:2px solid var(--line);background:var(--panel);border-radius:999px;padding:6px 12px;font-weight:700;cursor:pointer;color:var(--ink)}
.chips button:hover{border-color:var(--amber)}
.form-err{color:var(--bad);font-weight:700}

/* levels */
.playbar{display:flex;align-items:center;justify-content:space-between;gap:10px 18px;flex-wrap:wrap;margin-block:16px 8px}
.stat{display:flex;gap:16px;color:var(--muted);font-size:.95rem}
.stat b{font-family:var(--font-display);font-size:1.25rem;color:var(--ink);font-variant-numeric:tabular-nums}
.levels{display:grid;grid-template-columns:repeat(auto-fill,minmax(250px,1fr));gap:14px}
.level{display:flex;flex-direction:column;gap:8px;background:var(--panel);border:2px solid var(--line);border-radius:14px;padding:16px;min-width:0}
.level .num{font-family:var(--font-display);font-weight:700;font-size:.8rem;letter-spacing:.1em;text-transform:uppercase;color:var(--muted)}
.level h3{font-size:1.15rem}
.level .ops{font-family:var(--font-display);color:var(--amber-ink);background:var(--amber-soft);display:inline-block;padding:2px 8px;border-radius:6px;font-size:.95rem;align-self:flex-start}
.level .skill{color:var(--muted);font-size:.95rem}
.level .status{font-size:.95rem;min-height:1.5em;display:flex;align-items:center;gap:8px}
.level.locked{opacity:.6}
.level .btn{margin-top:auto;align-self:flex-start}
.star{color:var(--amber-ink);font-weight:700}

/* play */
.dots{display:flex;gap:7px;align-items:center}
.dot{width:14px;height:14px;border-radius:50%;background:var(--line)}
.dot.ok{background:var(--ok)}.dot.half{background:var(--amber)}.dot.bad{background:var(--bad)}
.dot.now{box-shadow:0 0 0 3px var(--amber-soft);background:var(--amber)}
.question{font-size:1.15rem}
.question b{color:var(--amber-ink);background:var(--amber-soft);padding:.05em .3em;margin-right:-.1em;border-radius:6px;white-space:nowrap}
.answer-row{display:flex;gap:10px;flex-wrap:wrap;align-items:stretch;margin-top:14px}
.answer-row input{flex:1 1 220px;min-width:0;font-size:1.4rem;font-weight:700;padding:8px 14px;border:2px solid var(--line);border-radius:10px;background:var(--panel-2);color:var(--ink);min-height:48px}
.answer-row input:focus{outline:3px solid var(--focus);outline-offset:1px;border-color:var(--focus)}
.answer-row input:disabled{opacity:.6}
.tip{margin-top:8px;color:var(--muted);font-size:.9rem}
.feedback{margin-top:12px;padding:12px 14px;border-radius:10px;border:2px solid var(--line);background:var(--panel-2);display:grid;gap:6px}
.feedback.ok{border-color:var(--ok);background:var(--ok-soft)}
.feedback.bad{border-color:var(--bad);background:var(--bad-soft)}
.feedback.hint{border-color:var(--amber);background:var(--amber-soft)}
.feedback .head{font-family:var(--font-display);font-size:1.15rem}
.steps{margin:2px 0 0;padding-left:1.2em;display:grid;gap:2px}
.gain{font-family:var(--font-display);color:var(--ok)}

/* summary */
.summary{display:grid;gap:10px;margin-top:16px}
.bignum{font-family:var(--font-display);font-size:clamp(2.4rem,8vw,4rem);line-height:1;color:var(--amber-ink)}
.bignum small{font-size:.35em;color:var(--muted)}

/* leaderboard */
.table-wrap{overflow-x:auto;background:var(--panel);border:2px solid var(--line);border-radius:14px}
.board{width:100%;border-collapse:collapse;font-variant-numeric:tabular-nums;min-width:420px}
.board th{font-family:var(--font-display);text-align:left;font-size:.8rem;letter-spacing:.08em;text-transform:uppercase;color:var(--muted);padding:12px 12px;border-bottom:2px solid var(--line)}
.board td{padding:11px 12px;border-bottom:1px solid var(--line)}
.board tr:last-child td{border-bottom:0}
.board tr.me td{background:var(--amber-soft)}
.board .num{text-align:right}
.board td.rank{color:var(--muted);width:2.5em}
.board td.pts{font-family:var(--font-display);font-size:1.1rem}
.lv{display:inline-flex;gap:3px;vertical-align:middle}
.lv span{width:10px;height:10px;border-radius:2px;background:var(--line)}
.lv span.d{background:var(--ok)}.lv span.p{background:var(--amber)}
.scope{display:inline-flex;align-items:center;gap:8px;font-size:.92rem;color:var(--muted)}
.scope::before{content:"";width:9px;height:9px;border-radius:50%;background:var(--muted)}
.scope.live::before{background:var(--ok);box-shadow:0 0 6px var(--ok)}

/* help */
.help{display:grid;gap:14px;margin-top:14px;max-width:70ch}
.help h3{font-size:1.1rem;margin-top:6px}
.example{display:inline-block;background:var(--panel-2);border:2px solid var(--line);border-radius:8px;padding:2px 10px;font-weight:700;white-space:nowrap}

/* settings overlay */
.overlay{position:fixed;inset:0;background:rgba(8,12,18,.6);display:flex;align-items:center;justify-content:center;padding:16px;z-index:50}
.sheet{background:var(--panel);border-radius:14px;padding:20px;max-width:440px;width:100%;display:grid;gap:12px;border:2px solid var(--line);max-height:100%;overflow:auto}
.row{display:flex;align-items:center;justify-content:space-between;gap:12px}
.row input[type=checkbox]{width:22px;height:22px;accent-color:var(--amber)}

/* avatar */
.av{width:100%;height:auto;display:block}
.av-stage{fill:var(--panel-2)}
.av-spin{animation:spin 1.1s linear infinite;transform-box:fill-box;transform-origin:center}
.av-bob{animation:bob 2.4s ease-in-out infinite;transform-box:fill-box;transform-origin:center}
.av-wobble{animation:wobble 1.8s ease-in-out infinite;transform-box:fill-box;transform-origin:50% 100%}
.av-flicker{animation:flicker .16s steps(2) infinite}
@keyframes bob{50%{transform:translateY(-6px)}}
@keyframes wobble{25%{transform:skewX(5deg)}75%{transform:skewX(-5deg)}}
@keyframes flicker{to{opacity:.55}}
.operator{width:clamp(82px,11vw,118px);align-self:center;margin-top:-6%}
.operator.hop .av{animation:hop .55s ease-out 2}
.operator.wob .av{animation:wob .45s ease-in-out 2}
@keyframes hop{35%{transform:translateY(-16px) rotate(-5deg)}70%{transform:translateY(0) rotate(0)}}
@keyframes wob{25%{transform:rotate(-8deg)}75%{transform:rotate(8deg)}}
.stage{grid-template-columns:auto 1fr var(--mw) 1fr}
@media (max-width:719px){.stage .operator{display:none}.stage{grid-template-columns:1fr var(--mw) 1fr}}
.nav .chip .dotc{width:28px;height:28px;border-radius:50%;overflow:hidden;background:var(--panel-2);display:inline-block}
.nav .chip .dotc .av{width:100%;height:100%}
.avcard{display:flex;gap:16px;align-items:center;flex-wrap:wrap;margin-bottom:14px}
.avcard .big{width:118px;flex:none;border-radius:16px;overflow:hidden;background:var(--panel-2)}
.avcard .txt{flex:1 1 220px;min-width:0;display:grid;gap:8px;justify-items:start}
.cog{display:inline-flex;align-items:center;gap:6px;font-family:var(--font-display);font-weight:700;font-size:1.1rem}
.cog svg{width:1.1em;height:1.1em;flex:none}
.cog svg path{fill:var(--brass);fill-rule:evenodd}
.dress{display:grid;grid-template-columns:minmax(220px,300px) 1fr;gap:16px;align-items:start}
@media (max-width:760px){.dress{grid-template-columns:1fr}.dress-preview{position:static}}
.dress-preview{display:grid;gap:12px;position:sticky;top:calc(12px + env(safe-area-inset-top,0px))}
.avatar-big{border-radius:18px;overflow:hidden;background:var(--panel-2);max-width:300px}
.swatches{display:flex;gap:8px;flex-wrap:wrap}
.swatch{width:30px;height:30px;border-radius:50%;border:3px solid;cursor:pointer;padding:0}
.swatch.on{outline:3px solid var(--ink);outline-offset:2px}
.swatch:focus-visible{outline:3px solid var(--focus);outline-offset:2px}
.tabs{display:flex;gap:6px;flex-wrap:wrap;margin-bottom:12px}
.tab{border:2px solid var(--line);background:var(--panel);border-radius:999px;padding:6px 12px;font-weight:700;cursor:pointer;color:var(--muted);min-height:40px}
.tab.on{background:var(--amber);border-color:var(--amber);color:#1b1300}
.tab:focus-visible{outline:3px solid var(--focus);outline-offset:2px}
.items{display:grid;grid-template-columns:repeat(auto-fill,minmax(140px,1fr));gap:10px}
.item{display:grid;gap:4px;text-align:left;background:var(--panel);border:2px solid var(--line);border-radius:14px;padding:10px;cursor:pointer;color:var(--ink);min-width:0;align-content:start}
.item:hover{border-color:var(--muted)}
.item:focus-visible{outline:3px solid var(--focus);outline-offset:2px}
.item .thumb{display:block;border-radius:10px;overflow:hidden;background:var(--panel-2)}
.item .iname{font-weight:700;line-height:1.25;margin-top:4px}
.item .iblurb{font-size:.85rem;color:var(--muted);line-height:1.3}
.item .iprice{font-family:var(--font-display);font-size:.9rem;color:var(--amber-ink)}
.item.owned .iprice{color:var(--ok)}
.item.wearing{border-color:var(--ok);box-shadow:0 0 0 3px var(--ok-soft)}
.item.locked{opacity:.6}
.item.cant .iprice{color:var(--bad)}
.toast{position:fixed;left:50%;bottom:calc(20px + env(safe-area-inset-bottom,0px));transform:translateX(-50%);background:var(--ink);color:var(--bg);padding:10px 16px;border-radius:10px;font-weight:700;z-index:60;box-shadow:0 10px 24px -10px rgba(0,0,0,.5);max-width:calc(100% - 32px)}
.board .pl{display:flex;align-items:center;gap:10px;min-width:0}
.board .pl .mini{width:32px;height:32px;border-radius:50%;overflow:hidden;background:var(--panel-2);flex:none}
.sumav{display:flex;gap:16px;align-items:center;flex-wrap:wrap}
.sumav .big{width:110px;flex:none;border-radius:16px;overflow:hidden;background:var(--panel-2)}

@media (prefers-reduced-motion:reduce){
  .gear path,.brand svg path,.machine.working,.machine.jam,.m-lamp.amber,.machine.working .m-display,.stage.running .belt,.av-spin,.av-bob,.av-wobble,.av-flicker,.operator.hop .av,.operator.wob .av{animation:none!important}
}

/* teacher console */
.tc{max-width:1100px}
.tc table{width:100%;border-collapse:collapse;font-variant-numeric:tabular-nums}
.tc th{font-family:var(--font-display);text-align:left;font-size:.78rem;letter-spacing:.08em;text-transform:uppercase;color:var(--muted);padding:10px 8px;border-bottom:2px solid var(--line)}
.tc td{padding:8px;border-bottom:1px solid var(--line);vertical-align:middle}
.tc td.actions{white-space:nowrap}
.tc td.actions form{display:inline}
.tc .mini-btn{font:inherit;font-size:.85rem;font-weight:700;padding:4px 9px;border-radius:7px;border:2px solid var(--line);background:var(--panel);color:var(--ink);cursor:pointer;margin:2px 2px 2px 0}
.tc .mini-btn:hover{border-color:var(--muted)}
.tc .mini-btn.danger{color:var(--bad);border-color:var(--bad)}
.tc input[type=text],.tc input[type=password],.tc input[type=number],.tc select{font:inherit;padding:6px 8px;border:2px solid var(--line);border-radius:8px;background:var(--panel-2);color:var(--ink);min-width:0}
.tc .inline{display:flex;gap:8px;flex-wrap:wrap;align-items:center}
.flash{padding:10px 14px;border-radius:10px;border:2px solid var(--ok);background:var(--ok-soft);margin-block:12px;font-weight:700}
.flash.bad{border-color:var(--bad);background:var(--bad-soft)}
.sysbox{display:grid;gap:4px;font-size:.92rem;color:var(--muted)}