/* Educativz Tools v3: matches the educativz.com theme (educativz-gp: system type, white/mist sections, black hero,
   green #067344 / #30d158 accent, blue links, 22/28px radii, pills) with the tools' own depth and motion layer. */
:root{--ez-font:-apple-system,BlinkMacSystemFont,"SF Pro Display","Segoe UI",Roboto,"Helvetica Neue",Arial,sans-serif;--mono:ui-monospace,"SF Mono",Menlo,Consolas,monospace;
--ink:#1d1d1f;--ink2:#6e6e73;--paper:#fff;--mist:#f5f5f7;--night:#000;--night2:#161617;--line:#d2d2d7;
--g:#067344;--g2:#0a8f55;--ghi:#30d158;--sky:#0066cc;--skyd:#2997ff;--amber:#ffb400;--amber-d:#c98500;--coral:#ff453a;--coral-d:#c0271e;
--r:22px;--r2:28px;--pill:980px;--ease:cubic-bezier(.25,.1,.25,1);--sh:0 10px 30px -14px rgba(0,0,0,.25)}
*{box-sizing:border-box}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%}
body{margin:0;font:17px/1.5 var(--ez-font);color:var(--ink);background:var(--paper);-webkit-font-smoothing:antialiased}
img,svg,canvas{max-width:100%}
a{color:var(--sky);text-decoration:none}a:hover{text-decoration:underline}
.sr{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap}
.skip{position:absolute;left:8px;top:-60px;background:#fff;color:var(--g);padding:10px 14px;border-radius:10px;z-index:99;font-weight:700}.skip:focus{top:8px}
:focus-visible{outline:3px solid var(--ghi);outline-offset:2px}
.wrap{width:min(1120px,100% - 40px);margin-inline:auto}
@media(max-width:600px){.wrap{width:min(1120px,100% - 32px)}}
.hud{font:600 13px/1 var(--mono);letter-spacing:.08em;text-transform:uppercase;color:var(--g)}.hero .hud{color:var(--ghi)}
/* ---------- header (site style: white bar, black text, green pill CTA) ---------- */
.top{position:sticky;top:0;z-index:50;background:rgba(255,255,255,.86);backdrop-filter:saturate(180%) blur(16px);-webkit-backdrop-filter:saturate(180%) blur(16px);border-bottom:1px solid rgba(0,0,0,.08)}
.top .wrap{display:flex;align-items:center;gap:10px;min-height:56px}
.brand{display:flex;align-items:center;gap:8px;font-weight:800;font-size:1.2rem;letter-spacing:-.02em;color:var(--ink)}
.brand:hover{text-decoration:none}
.brand i{display:grid;place-items:center;width:30px;height:30px;border-radius:9px;background:var(--g);color:#fff;font-style:normal;font-size:1rem;font-weight:900}
.top nav{margin-left:auto;display:flex;gap:2px;align-items:center}
.top nav a{color:var(--ink);font-weight:500;font-size:.95rem;padding:8px 12px;border-radius:var(--pill)}
.top nav a:hover{background:var(--mist);text-decoration:none}
.top nav a.hot{background:var(--g);color:#fff;font-weight:600;padding:8px 16px}
.top nav a.hot:hover{background:var(--g2)}
.snd{font:inherit;background:var(--mist);border:1px solid var(--line);color:var(--ink);border-radius:var(--pill);min-width:44px;min-height:40px;cursor:pointer;font-size:1rem}
@media(max-width:800px){.top nav a:not(.hot):not(.keep){display:none}}
/* ---------- hero (dark, like the home hero) ---------- */
.hero{position:relative;overflow:hidden;color:#fff;background:radial-gradient(900px 480px at 80% 0%,rgba(48,209,88,.28),transparent 60%),radial-gradient(600px 400px at 10% 100%,rgba(100,210,255,.16),transparent 60%),var(--night);padding:56px 0 110px;isolation:isolate}
#cast{position:absolute;inset:0;width:100%;height:100%;z-index:0;pointer-events:none;display:block}
#play{position:absolute;inset:0;width:100%;height:100%;z-index:1;touch-action:pan-y;display:block}
.hero .wrap{position:relative;z-index:2;pointer-events:none}
.hero .wrap a,.hero .wrap .badges{pointer-events:auto}
.hero .play-hint{position:absolute;right:16px;bottom:16px;z-index:2;font:500 12px var(--mono);color:#86868b;pointer-events:none}
@media(max-width:700px){.hero .play-hint{display:none}.hero{padding:40px 0 96px}}
.crumbs{font-size:.85rem;color:#a1a1a6;margin:0 0 14px}.crumbs a{color:#d2d2d7}
.eyebrow{display:block;color:var(--ghi);font-weight:600;font-size:.95rem;margin:0 0 8px}
.hero h1{margin:0 0 14px;font-size:clamp(36px,7vw,76px);line-height:1.04;letter-spacing:-.03em;font-weight:700;max-width:14em}
.hero h1 em{font-style:normal;background:linear-gradient(90deg,var(--ghi),#64d2ff);-webkit-background-clip:text;background-clip:text;color:transparent}
.quick{max-width:44em;margin:0;font-size:1.12rem;color:#d2d2d7;line-height:1.5}.quick strong{color:#fff}
.badges{display:flex;flex-wrap:wrap;gap:8px;margin:18px 0 0;padding:0;list-style:none}
.badges li{background:rgba(255,255,255,.1);border:1px solid rgba(255,255,255,.16);padding:6px 14px;border-radius:var(--pill);font-size:.86rem;font-weight:500;color:#f5f5f7}
/* ---------- panels / cards ---------- */
.main{padding:8px 0 30px}
.panel{position:relative;background:var(--paper);border-radius:var(--r2);box-shadow:0 1px 0 rgba(0,0,0,.04),0 24px 48px -28px rgba(0,0,0,.35);padding:26px;margin:-64px 0 36px;z-index:2}
.panel.flat{margin-top:0;background:var(--mist);box-shadow:none}
.panel h2{margin:0 0 4px;font-size:1.45rem;letter-spacing:-.02em;font-weight:700}
.panel .sub{margin:0 0 18px;color:var(--ink2);font-size:1rem}
.row{display:grid;gap:14px}.row.c2{grid-template-columns:repeat(auto-fit,minmax(230px,1fr))}.row.c3{grid-template-columns:repeat(auto-fit,minmax(170px,1fr))}
label,.lbl{display:block;font-weight:600;font-size:.92rem;margin-bottom:6px}
.hint{font-weight:400;color:var(--ink2);font-size:.84rem}
input,select,textarea{width:100%;font:inherit;color:var(--ink);background:var(--mist);border:1px solid transparent;border-radius:14px;padding:12px 14px;min-height:48px;transition:background .2s,box-shadow .2s,border-color .2s}
.panel.flat input,.panel.flat select,.panel.flat textarea{background:#fff}
input:focus,select:focus,textarea:focus{outline:none;background:#fff;border-color:var(--g);box-shadow:0 0 0 4px rgba(10,143,85,.18)}
textarea{min-height:130px;resize:vertical}
/* buttons: site pills with a keycap depth */
.btn{--c:var(--g);--cd:#04492b;display:inline-flex;align-items:center;justify-content:center;gap:8px;font:inherit;font-weight:600;color:#fff;background:var(--c);border:0;border-radius:var(--pill);padding:12px 22px;min-height:46px;cursor:pointer;box-shadow:0 4px 0 var(--cd),0 10px 20px -10px rgba(0,0,0,.4);transform:translateY(0);transition:transform .08s,box-shadow .08s,filter .2s;touch-action:manipulation}
.btn:hover{filter:brightness(1.08);text-decoration:none;color:#fff}
.btn:active,.btn.on,.btn.press{transform:translateY(3px);box-shadow:0 1px 0 var(--cd),0 4px 8px -4px rgba(0,0,0,.35)}
.btn.amber{--c:var(--amber);--cd:var(--amber-d);color:#1d1d1f}.btn.amber:hover{color:#1d1d1f}
.btn.coral{--c:var(--coral);--cd:var(--coral-d)}.btn.sky{--c:var(--sky);--cd:#003f80}
.btn.ghost{--c:#e8e8ed;--cd:#c7c7cc;color:var(--ink)}.btn.ghost:hover{color:var(--ink)}
.btn.sm{min-height:40px;padding:7px 14px;font-size:.88rem;box-shadow:0 3px 0 var(--cd)}
.btn[disabled]{opacity:.45;cursor:not-allowed;transform:none}
.btns{display:flex;flex-wrap:wrap;gap:12px;align-items:center;margin-top:16px}
.icon-btn{font:inherit;width:44px;height:44px;border-radius:50%;border:1px solid var(--line);background:#fff;color:var(--ink);cursor:pointer;font-size:1.1rem;transition:transform .15s,background .15s}
.icon-btn:hover{background:var(--mist)}.icon-btn:active{transform:scale(.92)}
.chips{display:flex;flex-wrap:wrap;gap:8px}
.chip{font:inherit;font-weight:600;font-size:.9rem;padding:9px 16px;min-height:40px;border-radius:var(--pill);border:1px solid var(--line);background:#fff;color:var(--ink);cursor:pointer;transition:transform .1s,background .15s,border-color .15s,color .15s}
.chip:hover{border-color:var(--ink)}
.chip[aria-pressed=true],.chip.on{background:var(--ink);border-color:var(--ink);color:#fff}
.chip:active,.chip.press{transform:scale(.96)}
/* result display: dark card like the site's dark sections */
.display{background:var(--night);color:#fff;border-radius:var(--r);padding:20px 22px;position:relative;overflow:hidden}
.display:before{content:"";position:absolute;inset:0;background:radial-gradient(500px 200px at 100% 0%,rgba(48,209,88,.25),transparent 70%)}
.display>*{position:relative}
.display .k{font-size:.8rem;letter-spacing:.06em;text-transform:uppercase;color:#a1a1a6;font-weight:600}
.display .v{font:700 clamp(2rem,7vw,3.2rem)/1.08 var(--ez-font);letter-spacing:-.03em;font-variant-numeric:tabular-nums;color:var(--ghi)}
.display .v small{font-size:.45em;color:#d2d2d7;font-weight:600;letter-spacing:0}
.display .note{margin:6px 0 0;color:#d2d2d7;font-size:.92rem}
.stats{display:grid;grid-template-columns:repeat(auto-fit,minmax(150px,1fr));gap:12px;margin-top:14px}
.stat{background:var(--mist);border-radius:18px;padding:14px 16px;transition:box-shadow .2s}
.stat:hover{box-shadow:var(--sh)}
.panel.flat .stat{background:#fff}
.stat .k{font-size:.78rem;font-weight:600;color:var(--ink2);text-transform:uppercase;letter-spacing:.05em}
.stat .v{font-size:1.45rem;font-weight:700;font-variant-numeric:tabular-nums;letter-spacing:-.02em;color:var(--ink)}
.pop{animation:pop .4s cubic-bezier(.2,1.6,.4,1)}@keyframes pop{from{transform:scale(.96) translateY(6px)}}
.ok{color:#0a8f55}.bad{color:#d70015}.warn{color:#b25000}
.msg{padding:12px 16px;border-radius:14px;font-weight:500;margin-top:14px}
.msg.ok{background:#e3f8ea;color:#0a5a30}.msg.bad{background:#ffe5e3;color:#8a1e14}.msg.warn{background:#fff3d6;color:#6b4800}
.tw{overflow-x:auto;border-radius:16px;border:1px solid var(--line);background:#fff}
table{border-collapse:collapse;width:100%;font-size:.94rem}
th,td{padding:11px 14px;text-align:left;border-bottom:1px solid var(--line)}
th{background:var(--mist);font-size:.78rem;text-transform:uppercase;letter-spacing:.05em;color:var(--ink2)}
td.n,th.n{text-align:right;font-variant-numeric:tabular-nums}tr:last-child td{border-bottom:0}
/* ---------- long content ---------- */
.content{max-width:820px}
.content h2{font-size:clamp(26px,4vw,38px);letter-spacing:-.025em;margin:56px 0 12px;line-height:1.12;font-weight:700;transform:translateY(16px);transition:transform .6s var(--ease)}
.content h2.seen{transform:none}
.content h3{font-size:1.2rem;margin:24px 0 6px;font-weight:600}
.content p,.content li{color:#3a3a3c}
.content ol,.content ul{padding-left:22px}
.steps{counter-reset:s;list-style:none;padding:0}
.steps li{counter-increment:s;position:relative;padding:16px 18px 16px 66px;margin:0 0 12px;background:var(--mist);border-radius:18px;transform:translateX(-18px);transition:transform .55s var(--ease)}
.steps li.seen{transform:none}
.steps li:before{content:counter(s);position:absolute;left:16px;top:14px;width:36px;height:36px;border-radius:50%;background:var(--g);color:#fff;font-weight:700;display:grid;place-items:center}
.box{background:var(--mist);border-radius:18px;padding:16px 18px;margin:16px 0}
.box.warn{background:#fff3d6}
.src{font-size:.9rem;color:var(--ink2)}
details.faq{background:#fff;border-bottom:1px solid var(--line);margin:0;overflow:hidden}
details.faq summary{cursor:pointer;list-style:none;padding:16px 48px 16px 0;font-weight:600;font-size:1.05rem;position:relative}
details.faq summary::-webkit-details-marker{display:none}
details.faq summary:after{content:"+";position:absolute;right:4px;top:50%;transform:translateY(-50%);width:28px;height:28px;border-radius:50%;background:var(--mist);color:var(--ink);display:grid;place-items:center;font-weight:600;transition:transform .25s var(--ease),background .2s}
details.faq[open] summary:after{content:"–";background:var(--ink);color:#fff}
details.faq .ans{padding:0 0 16px;color:#3a3a3c}
.by{font-size:.88rem;color:var(--ink2);border-top:1px solid var(--line);padding-top:14px;margin-top:34px}
/* ---------- ads ---------- */
.ad{display:none;margin:28px auto;max-width:100%;min-height:280px;text-align:center;overflow:hidden}.ad.on{display:block}
.ad small{display:block;font-size:.7rem;letter-spacing:.08em;color:#86868b;text-transform:uppercase;margin-bottom:4px}.ad ins{display:block;min-height:250px;width:100%}
/* ---------- tool cards (grid + ring + rack) ---------- */
.grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(250px,1fr));gap:16px;perspective:1000px}
.tcard{position:relative;display:flex;flex-direction:column;gap:6px;background:var(--mist);border-radius:var(--r);padding:20px;color:var(--ink);transition:transform .25s var(--ease),box-shadow .25s,background .25s;transform-style:preserve-3d}
.tcard:hover{background:#fff;box-shadow:0 30px 50px -30px rgba(0,0,0,.45);text-decoration:none}
.tcard .ic{width:56px;height:56px;border-radius:16px;display:grid;place-items:center;font-size:1.7rem;color:#fff;background:linear-gradient(145deg,var(--c1,#30d158),var(--c2,#067344));transform:translateZ(30px);box-shadow:0 10px 20px -10px var(--c3,#04492b)}
.tcard h3{margin:6px 0 0;font-size:1.12rem;letter-spacing:-.01em;font-weight:600;transform:translateZ(14px)}
.tcard p{margin:0;color:var(--ink2);font-size:.92rem}
.tcard .go{margin-top:auto;padding-top:8px;font-weight:600;color:var(--sky)}
.tag{position:absolute;right:14px;top:14px;background:var(--ghi);color:#003d17;font-size:.68rem;font-weight:800;padding:4px 10px;border-radius:var(--pill);letter-spacing:.06em}
.tag.old{background:#e8e8ed;color:var(--ink2)}
.tcard:active{transform:scale(.98)!important}
/* chapter sections (hub) */
.chapter{padding:48px 0 8px}
.chapter .hud{display:block;margin:0 0 6px}
.chapter h2{margin:0 0 6px;font-size:clamp(26px,4.5vw,44px);letter-spacing:-.025em;line-height:1.1;font-weight:700;transform:translateY(18px);transition:transform .7s var(--ease)}
.chapter.seen h2{transform:none}
.chapter .lead{margin:0 0 18px;color:var(--ink2);max-width:46em}
/* 3D ring */
.ring3d{position:relative;perspective:1200px;perspective-origin:50% 40%;margin:18px 0 0;touch-action:pan-y;outline:none}
.ring3d ul{list-style:none;margin:0;padding:0;position:relative;height:300px;transform-style:preserve-3d;will-change:transform}
.ring3d li{position:absolute;left:50%;top:0;width:min(290px,78vw);margin-left:calc(min(290px,78vw) / -2);transform:rotateY(var(--a)) translateZ(var(--R));transform-style:preserve-3d;backface-visibility:hidden}
.ring3d li .tcard{height:100%;background:#fff;box-shadow:0 20px 40px -24px rgba(0,0,0,.5);transform:scale(calc(1 - var(--d,0) * .12))}
.ring3d li .tcard:after{content:"";position:absolute;inset:0;border-radius:inherit;background:#000;opacity:calc(var(--d,0) * .35);pointer-events:none}
.ring3d li.front .tcard{box-shadow:0 36px 60px -28px rgba(0,0,0,.55)}
.ring3d.live ul{cursor:grab}.ring3d.drag ul{cursor:grabbing}
.ring3d.flat{perspective:none}.ring3d.flat ul{display:flex;gap:14px;height:auto;overflow-x:auto;scroll-snap-type:x mandatory;padding-bottom:10px;transform:none!important}
.ring3d.flat li{position:static;width:min(290px,78vw);flex:0 0 auto;margin:0;transform:none;scroll-snap-align:center}
.ring-ctl{display:flex;align-items:center;justify-content:center;gap:16px;margin:14px 0 0}.ring-ctl .hud{color:var(--ink2)}
/* hanging rack */
.rackwrap{position:relative;margin:18px 0 0}
.rackwrap .rail{height:6px;border-radius:3px;background:linear-gradient(90deg,#c7c7cc,#8e8e93,#c7c7cc);margin:0 10px 14px;box-shadow:0 2px 0 rgba(0,0,0,.15)}
.rack{display:flex;gap:16px;overflow-x:auto;scroll-snap-type:x mandatory;padding:4px 10px 18px;-webkit-overflow-scrolling:touch;scrollbar-width:none;touch-action:pan-y}
.rack::-webkit-scrollbar{display:none}
.rack.live{overflow:visible;scroll-snap-type:none;transform:translateX(var(--x,0));will-change:transform;cursor:grab}
.rackwrap.drag .rack.live{cursor:grabbing}
.rackwrap.live{overflow:hidden}
.hang{flex:0 0 auto;width:min(250px,72vw);scroll-snap-align:center;transform-origin:50% -24px;position:relative}
.hang:before{content:"";position:absolute;left:50%;top:-18px;width:14px;height:22px;margin-left:-7px;border-radius:4px 4px 2px 2px;background:linear-gradient(#f5f5f7,#8e8e93);box-shadow:0 2px 0 rgba(0,0,0,.2)}
.hang .tcard{background:#fff;border:1px solid var(--line)}
.rack-ctl{display:flex;align-items:center;gap:12px;margin-top:4px;padding:0 10px}
.rbar{flex:1;height:4px;border-radius:2px;background:#e8e8ed;overflow:hidden}.rbar i{display:block;height:100%;width:0;background:var(--ink);border-radius:2px;transition:width .15s}
/* ---------- footer ---------- */
.foot{background:var(--mist);color:var(--ink2);padding:40px 0;font-size:.86rem;margin-top:40px;border-top:1px solid var(--line)}
.foot .cols{display:grid;grid-template-columns:repeat(auto-fit,minmax(165px,1fr));gap:22px 26px}
.foot h3{margin:0 0 8px;color:var(--ink);font-size:.8rem;text-transform:uppercase;letter-spacing:.08em;font-weight:600}
.foot ul{list-style:none;margin:0;padding:0}.foot li{margin:5px 0}
.foot a{color:var(--ink2)}.foot a:hover{color:var(--ink)}
.foot .soc a{display:inline-block;margin:4px 12px 4px 0;padding:8px 0;font-weight:600;color:var(--sky)}
.foot p{margin:18px 0 0;max-width:60em}
/* ---------- file tools ---------- */
.drop{border:2px dashed #c7c7cc;border-radius:var(--r);background:var(--mist);padding:30px 16px;text-align:center;cursor:pointer;transition:transform .2s var(--ease),border-color .2s,background .2s}
.drop:hover{border-color:var(--g)}
.drop.over{border-color:var(--ghi);transform:scale(1.015);background:#e3f8ea}
.drop b{display:block;font-size:1.1rem;font-weight:600}
.files{list-style:none;padding:0;margin:14px 0 0;display:grid;gap:10px}
.files li{display:flex;align-items:center;gap:12px;background:var(--mist);border-radius:16px;padding:8px 10px;animation:pop .35s cubic-bezier(.2,1.5,.4,1)}
.files img,.files .pg{width:52px;height:52px;object-fit:cover;border-radius:10px;background:#fff;display:grid;place-items:center;font-weight:700;color:var(--g)}
.files .nm{flex:1;min-width:0;font-weight:600;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.files .nm small{display:block;color:var(--ink2);font-weight:400}
.files .btn{min-height:40px;min-width:40px;padding:4px 10px;box-shadow:0 3px 0 var(--cd)}
.bar{height:10px;border-radius:5px;background:#e8e8ed;overflow:hidden}.bar i{display:block;height:100%;width:0;background:linear-gradient(90deg,var(--g2),var(--ghi));border-radius:5px;transition:width .2s}
/* gauges */
.gauge{margin:14px 0 4px}.gauge svg{width:100%;height:auto;display:block;overflow:visible}
.ring{display:grid;place-items:center;position:relative;margin:12px auto 0}
.ring svg{width:150px;height:150px;transform:rotate(-90deg)}
.ring .lab{position:absolute;text-align:center;font-weight:700;font-size:1.25rem;line-height:1.05;font-variant-numeric:tabular-nums}
.ring .lab small{display:block;font-size:.7rem;font-weight:600;color:var(--ink2);text-transform:uppercase;letter-spacing:.06em}
@media(prefers-reduced-motion:reduce){*,*:before,*:after{animation:none!important;transition:none!important;scroll-behavior:auto!important}.content h2,.steps li,.chapter h2{transform:none!important}}
@media print{.top,#play,#cast,.ad,.foot,.btns,.ring-ctl,.rack-ctl{display:none}}
/* hero text keeps clear of the cast (right side) */
@media(min-width:900px){.hero .wrap{padding-right:min(36%,400px)}}
@media(max-width:899px){.hero{padding-bottom:170px}.hero .wrap{padding-right:0}}
.ring3d{overflow:hidden;padding:10px 0 20px}
.chapter,.main{overflow-x:clip}
@media(max-width:600px){.top nav a:not(.hot){display:none}.brand{font-size:1.1rem}}
.content p a,.ans a,.quick a,.lead a,.box a,.src a{text-decoration:underline;text-underline-offset:3px}
/* mobile fixes: text above the tokens, gradient descenders not clipped, flat compact grid */
.hero .wrap{z-index:3}
.hero h1 em{display:inline;padding-bottom:.15em}
@media(max-width:700px){
.grid{perspective:none;grid-template-columns:repeat(2,minmax(0,1fr));gap:10px}
.tcard{transform-style:flat;padding:14px 12px 12px;gap:4px;border-radius:18px}
.tcard .ic,.tcard h3{transform:none}
.tcard .ic{width:40px;height:40px;border-radius:12px;font-size:1.25rem;box-shadow:none}
.tcard h3{font-size:.95rem;line-height:1.2;margin-top:4px}
.tcard p{font-size:.78rem;line-height:1.35}
.tcard .go{font-size:.82rem;padding-top:6px}
.tag{right:8px;top:8px;font-size:.6rem;padding:3px 7px}
.ring3d li .tcard,.hang .tcard{padding:18px}
}