@import"https://fonts.googleapis.com/css2?family=DM+Mono:wght@400;500&family=Manrope:wght@400;500;600;700;800&display=swap";:root{font-family:Manrope,sans-serif;color:#17201c;background:#f4f3ed;font-synthesis:none;--ink:#17201c;--muted:#68716c;--paper:#fbfaf5;--line:#dcded7;--green:#145c43;--lime:#dff369;--orange:#f17b45}*{box-sizing:border-box}body{margin:0;min-width:320px}button,input,textarea{font:inherit}button{cursor:pointer;min-height:42px;border:1px solid var(--ink);border-radius:6px;padding:0 17px;color:var(--ink);background:transparent;font-weight:700}button:hover:not(:disabled){transform:translateY(-1px);box-shadow:2px 2px 0 var(--ink)}button:disabled{opacity:.55;cursor:wait}button.primary,.send{color:#fff;background:var(--ink)}.eyebrow{font:500 .7rem DM Mono,monospace;text-transform:uppercase;letter-spacing:.12em;color:var(--green)}.landing{min-height:100vh;display:grid;grid-template-columns:1.1fr .9fr;overflow:hidden;background:var(--paper)}.landing-copy{align-self:center;padding:clamp(40px,8vw,120px);max-width:820px}.landing h1{margin:12px 0 22px;font-size:clamp(4.5rem,10vw,9rem);line-height:.82;letter-spacing:-.09em}.landing p{max-width:540px;font-size:clamp(1rem,2vw,1.35rem);line-height:1.55;color:var(--muted)}.actions{display:flex;gap:12px;margin-top:35px}.landing-art{position:relative;min-height:100vh;background:var(--green)}.landing-art span{position:absolute;display:block;border:2px solid #e9ff88;border-radius:50%}.landing-art span:nth-child(1){width:320px;height:320px;top:14%;left:12%}.landing-art span:nth-child(2){width:480px;height:480px;top:26%;left:24%}.landing-art span:nth-child(3){width:22px;height:22px;top:30%;left:30%;background:var(--lime)}.landing-art span:nth-child(4){width:72px;height:72px;bottom:20%;right:19%;background:var(--orange);border:0}.auth-page{min-height:100vh;display:grid;place-items:center;padding:24px;background:var(--green);color:#fff}.loading{min-height:100vh;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:12px;padding:24px;background:var(--green);color:#fff}.loading p{margin:0}.loading button{color:#fff;border-color:#fff}.auth-panel{width:min(460px,100%);display:grid;gap:20px;background:var(--paper);color:var(--ink);padding:44px;box-shadow:12px 12px #0b3e2c}.auth-panel h1{margin:0 0 12px;font-size:2.6rem;line-height:1;letter-spacing:-.06em}.auth-panel label{display:grid;gap:8px;font-size:.78rem;font-weight:800;text-transform:uppercase;letter-spacing:.06em}.auth-panel input{min-height:50px;padding:0 14px;border:1px solid #aeb5af;border-radius:4px;background:#fff}.back{border:0;padding:0;min-height:auto;justify-self:start;color:var(--green)}.error{color:#b73822;font-size:.86rem}.pulse{width:16px;height:16px;border-radius:50%;background:var(--lime);animation:pulse 1s infinite alternate;margin:auto auto 12px}@keyframes pulse{to{transform:scale(1.7);opacity:.5}}.app-shell{min-height:100vh;display:grid;grid-template-columns:300px 1fr;grid-template-rows:72px calc(100vh - 72px);grid-template-areas:"top top" "case work"}.topbar{grid-area:top;display:grid;grid-template-columns:300px 1fr auto;align-items:center;border-bottom:1px solid var(--line);background:var(--paper)}.wordmark{padding-left:28px;color:var(--ink);font-weight:800;font-size:1.4rem;text-decoration:none;letter-spacing:-.05em}.wordmark span{color:var(--orange)}.box-title{height:100%;display:flex;align-items:center;gap:14px;border-left:1px solid var(--line);padding:0 28px}.box-title small{font:500 .64rem DM Mono;text-transform:uppercase;color:var(--muted)}.box-title strong{font-size:.92rem}.profile{display:flex;align-items:center;gap:15px;padding-right:22px;font-size:.8rem;font-weight:700}.quiet{border:0;min-height:34px;padding:0 8px;color:var(--muted);font-size:.75rem}.quiet:hover:not(:disabled){box-shadow:none;color:var(--ink)}.case-panel{grid-area:case;border-right:1px solid var(--line);padding:35px 28px 24px;background:#ecece5;display:flex;flex-direction:column;gap:28px;overflow:auto}.case-panel h2{font-size:1.7rem;letter-spacing:-.055em;line-height:1.14;margin:9px 0 15px}.case-panel p{font-size:.85rem;line-height:1.6;color:var(--muted)}.case-evidence{display:grid;gap:8px}.case-evidence div{padding:10px 11px;background:#f6f6f0;border-left:3px solid var(--green)}.case-evidence div+div{border-left-color:var(--orange)}.case-evidence span{font:500 .58rem DM Mono;text-transform:uppercase;color:var(--muted)}.case-evidence p{margin:3px 0 0;font-size:.68rem;line-height:1.4;color:var(--ink)}.constraints{display:grid;margin:0;border-top:1px solid #cfd2ca}.constraints div{display:flex;justify-content:space-between;border-bottom:1px solid #cfd2ca;padding:11px 0;font-size:.72rem}.constraints dt{color:var(--muted)}.constraints dd{margin:0;font-weight:800}.progress-card{display:grid;gap:11px}.progress-card>div:first-child{display:flex;justify-content:space-between;font:500 .68rem DM Mono;text-transform:uppercase}.progress-track{height:5px;background:#d3d6cd}.progress-track i{display:block;height:100%;background:var(--green);transition:width .4s}.progress-card ul{list-style:none;margin:5px 0 0;padding:0;display:grid;gap:9px}.progress-card li{display:grid;grid-template-columns:10px 1fr;gap:8px;color:#8b918d;font-size:.67rem;line-height:1.35}.progress-card li i{width:8px;height:8px;border:1px solid #a6ada7;border-radius:50%;margin-top:1px}.progress-card li.done{color:var(--ink)}.progress-card li.done i{background:var(--green);border-color:var(--green)}.engine-note{margin-top:auto;font:400 .62rem DM Mono;color:var(--muted);display:flex;align-items:center;gap:7px}.engine-note i{width:7px;height:7px;border-radius:50%;background:#d9a437}.engine-note i.openrouter{background:#29a36a}.workspace{grid-area:work;min-width:0;background:var(--paper);display:grid;grid-template-rows:47px 1fr}.workspace-head{border-bottom:1px solid var(--line);padding:0 28px;display:flex;align-items:center;justify-content:space-between;font:500 .68rem DM Mono;text-transform:uppercase;color:var(--muted)}.workspace-head>div:first-child{display:flex;align-items:center;gap:8px}.phase-dot{width:7px;height:7px;border-radius:50%;background:var(--orange)}.classroom-tools{display:flex;gap:4px}.classroom-tools{align-items:center}.classroom-clock{color:var(--green);font-weight:700}.concept-label{max-width:210px;overflow:hidden;text-overflow:ellipsis;white-space:nowrap;text-transform:none}.learning-grid{min-height:0;display:grid;grid-template-columns:minmax(0,760px);justify-content:center}.learning-grid.with-board{grid-template-columns:minmax(420px,1.05fr) minmax(400px,.95fr);justify-content:stretch}.conversation{min-height:0;display:flex;flex-direction:column;padding:0 34px 25px;max-width:820px;width:100%;margin:0 auto}.thread{flex:1;overflow:auto;padding:34px 3px 20px;scrollbar-width:thin}.message{display:grid;grid-template-columns:32px 1fr;gap:11px;margin-bottom:27px;max-width:670px}.message.learner{margin-left:43px}.avatar{width:30px;height:30px;display:grid;place-items:center;border-radius:50%;background:var(--ink);color:#fff;font:500 .7rem DM Mono}.message.learner .avatar{background:var(--lime);color:var(--ink)}.message.teacher .avatar{background:var(--green)}.message.student .avatar{background:var(--orange)}.speaker{display:block;margin:0 0 6px;font:500 .62rem DM Mono;text-transform:uppercase;letter-spacing:.08em;color:var(--muted)}.message p{margin:0;white-space:pre-wrap;font-size:.92rem;line-height:1.65}.message.box p,.message.teacher p{font-size:1rem}.fallback-label{display:inline-block;margin-top:8px;font:500 .56rem DM Mono;text-transform:uppercase;letter-spacing:.06em;color:#9a6a23}.message .human-prompt{margin-top:10px;padding:8px 11px;border-left:2px solid var(--lime);background:#f3f6df;font-size:.76rem;font-weight:700}.composer{border:1px solid #bdc2bb;background:#fff;border-radius:8px;box-shadow:4px 4px #e0e1da;overflow:hidden;flex:none}.composer textarea{width:100%;border:0;resize:none;padding:16px 17px 8px;outline:0;line-height:1.5;background:transparent}.composer>div{display:flex;justify-content:space-between;align-items:center;padding:4px 8px 8px 16px}.composer>div span{font:400 .6rem DM Mono;color:#989f99}.send{min-height:35px;border:0;font-size:.72rem}.send:hover:not(:disabled){box-shadow:none;transform:none}.classroom-offer{display:grid;grid-template-columns:46px 1fr;gap:16px;padding:22px;margin:0 0 22px;background:#ecf2cf;border:1px solid #a5af6f;box-shadow:4px 4px #d9dec0}.offer-icon{width:44px;height:44px;display:grid;place-items:center;border-radius:50%;background:var(--lime);font-size:1.3rem}.classroom-offer h3{margin:6px 0;font-size:1.1rem}.classroom-offer p{margin:0;color:var(--muted);font-size:.8rem}.offer-actions{display:flex;gap:8px;margin-top:15px}.offer-actions button{min-height:36px;font-size:.72rem}.direction{width:100%;min-height:auto;margin:0 0 16px;padding:12px 14px;border:1px dashed #9da48f;background:#f4f5e9;text-align:left;font:500 .69rem DM Mono;line-height:1.5;color:var(--green)}.application-tag{margin:0 0 22px 43px;padding:10px 14px;border-left:3px solid var(--orange);background:#fce9df;font:500 .65rem DM Mono;color:#844328}.completion{display:flex;gap:16px;align-items:flex-start;margin-bottom:20px;padding:22px;background:#e5efcd;border:1px solid #a1ad79}.completion>span{flex:none;width:40px;height:40px;display:grid;place-items:center;background:var(--green);color:#fff;border-radius:50%}.completion h3,.completion p{margin:0}.completion p{font-size:.78rem;color:var(--muted);margin-top:3px}.completion ol{margin:12px 0 0;padding-left:18px;font:400 .66rem DM Mono;line-height:1.7;color:var(--green)}.visual-board{border-left:1px solid var(--line);background:#eff0e9;min-width:0;display:flex;flex-direction:column;padding:27px;overflow:auto}.board-head{display:flex;justify-content:space-between;align-items:start}.board-head h3{margin:5px 0;font-size:1.25rem}.scene-version{font:400 .65rem DM Mono;color:var(--muted)}.diagram{position:relative;min-height:480px;margin-top:28px;border:1px solid #cbd0c6;background-image:linear-gradient(#dfe2da 1px,transparent 1px),linear-gradient(90deg,#dfe2da 1px,transparent 1px);background-size:24px 24px;background-color:#f8f8f3;overflow:hidden}.diagram-item{position:absolute;left:7%;width:125px;min-height:46px;padding:8px 10px;border:1px solid var(--ink);background:#fff;box-shadow:3px 3px 0 var(--lime);z-index:2}.diagram-item span{display:block;font-size:.74rem;font-weight:800}.diagram-item small{font:400 .62rem DM Mono;color:var(--green)}.diagram-item:after{content:"";position:absolute;left:100%;top:50%;width:clamp(50px,10vw,120px);border-top:1px dashed var(--green)}.diagram-item.collision{box-shadow:3px 3px 0 var(--orange)}.bit-array{position:absolute;right:7%;top:120px;width:55%;padding:18px;background:#fff;border:1px solid #aeb5ad;transition:.3s}.bit-array.focused{border-color:var(--green);box-shadow:0 0 0 3px #dff36988}.array-label{font:500 .65rem DM Mono;text-transform:uppercase;margin-bottom:13px}.bits{display:grid;grid-template-columns:repeat(8,1fr);gap:3px}.bits>button{position:relative;min-height:0;padding:0;border:0;border-radius:0;aspect-ratio:1;display:grid;place-items:center;background:#e6e8e1;font:500 .75rem DM Mono}.bits>button:hover:not(:disabled){transform:none;box-shadow:inset 0 0 0 2px var(--orange)}.bits>button.marked{background:var(--green);color:#fff;animation:mark .45s ease-out}.bits>button.selected{box-shadow:inset 0 0 0 3px var(--orange)}.bits small{position:absolute;top:calc(100% + 5px);color:var(--muted);font-size:.5rem}@keyframes mark{0%{transform:scale(.5);background:var(--lime)}}.check-card{position:absolute;right:9%;bottom:55px;width:50%;padding:15px;border-left:4px solid var(--orange);background:#fff1e9;display:grid;gap:5px}.check-card span{font:500 .6rem DM Mono;text-transform:uppercase;color:#a54f28}.check-card strong{font:500 1rem DM Mono}.check-card small{font-size:.63rem;color:var(--muted)}.comparison-panel{position:absolute;right:9%;width:50%;padding:15px;border-left:4px solid var(--lime);background:#f3f6df;font-size:.72rem;font-weight:800}.diagram-actions{display:flex;justify-content:space-between;align-items:center;gap:10px;padding-top:12px}.diagram-actions span{font:400 .62rem DM Mono;color:var(--muted)}.diagram-actions button{min-height:34px;font-size:.68rem}.empty-board{height:450px;display:grid;place-content:center;text-align:center;color:var(--muted);padding:40px}.empty-board i{font-style:normal;font-size:2rem}.empty-board p{font-size:.8rem;max-width:220px;line-height:1.5}.accessible-summary{font-size:.67rem;line-height:1.5;color:var(--muted);margin-top:14px}@media(max-width:1050px){.app-shell{grid-template-columns:240px 1fr}.topbar{grid-template-columns:240px 1fr auto}.learning-grid.with-board{grid-template-columns:1fr}.visual-board{border-left:0;border-top:1px solid var(--line);min-height:550px}.workspace{overflow:auto}.learning-grid{min-height:auto}.conversation{min-height:680px}.case-panel{padding:28px 20px}}@media(max-width:720px){.landing{grid-template-columns:1fr}.landing-art{display:none}.app-shell{display:block}.topbar{position:sticky;top:0;z-index:5;display:flex;height:64px;padding:0 16px}.wordmark{padding:0}.box-title{display:none}.profile{margin-left:auto;padding:0}.profile>span{display:none}.case-panel{border:0;border-bottom:1px solid var(--line);padding:22px}.constraints,.progress-card ul{display:none}.workspace{display:block}.workspace-head{height:44px;padding:0 16px}.conversation{padding:0 16px 18px;min-height:70vh}.visual-board{padding:20px}.learning-grid.with-board{display:flex;flex-direction:column}.diagram{min-height:400px}.composer>div span{display:none}.auth-panel{padding:30px}.landing-copy{padding:50px 28px}.landing h1{font-size:4.7rem}}@media(prefers-reduced-motion:reduce){*,*:before,*:after{animation-duration:.01ms!important;animation-iteration-count:1!important;scroll-behavior:auto!important;transition-duration:.01ms!important}}