:root{color-scheme:light;--ink:#243e35;--muted:#586b61;--forest:#205c49;--green:#e3efe7;--cream:#f7f7f0;--line:#dbe3d9;--gold:#f5c86e;--paper:#fff;--serif:Georgia,'Times New Roman',serif;font-family:'Segoe UI',Arial,sans-serif;color:var(--ink);background:var(--cream);font-size:16px}*{box-sizing:border-box}body{margin:0}a{color:var(--forest)}button,input,select,textarea{font:inherit}button,a,input,select,summary,textarea{touch-action:manipulation}button{cursor:pointer}button:disabled{cursor:default;opacity:.6}button:focus-visible,a:focus-visible,input:focus-visible,select:focus-visible,textarea:focus-visible,summary:focus-visible{outline:3px solid #98700e;outline-offset:4px}h1,h2,h3,h4,p{margin-top:0}h1,h2,h3,h4,strong,b{font-weight:400}p{line-height:1.65}header,main,footer{max-width:1280px;margin:auto}header{display:flex;justify-content:space-between;align-items:center;padding:25px 44px;border-bottom:1px solid var(--line)}.brand{display:flex;align-items:center;gap:9px;text-decoration:none;font-size:26px;letter-spacing:-1px}.brand-icon{font-family:var(--serif);font-size:36px;line-height:1}.brand-icon span{color:#be8525}.grade{font:10px 'Segoe UI',sans-serif;letter-spacing:1.5px;margin-left:16px;border-left:1px solid #bccabe;padding-left:20px}.back{font-size:14px;text-decoration:none}.back span{font-size:22px;margin-left:15px}main{padding:0 44px}.hero{display:grid;grid-template-columns:1.3fr 1fr;gap:36px;align-items:center;padding:54px 0 40px}.eyebrow{font-size:11px;letter-spacing:2px;line-height:1.6;color:var(--forest);margin-bottom:16px}h1{font-family:var(--serif);font-size:clamp(36px,4.3vw,58px);line-height:1.07;letter-spacing:-1.5px;margin-bottom:24px}.subtitle{font-size:19px;margin-bottom:12px}.intro{font-size:15px;color:var(--muted)}.hero-chips{display:flex;flex-wrap:wrap;gap:8px;margin-top:24px}.hero-chips span,.count-pill{border:1px solid #d2dfd1;border-radius:20px;font-size:11px;padding:7px 11px}.hero-art{position:relative;padding:18px 0 0}.hero-art svg{width:100%;display:block}.ruler-decoration{position:absolute;transform:rotate(-9deg);right:0;top:0;background:var(--gold);padding:10px 20px;color:#705321;font-size:15px;letter-spacing:2px;box-shadow:2px 8px 0 #203e3410}.art-note{display:block;text-align:center;font-size:12px;letter-spacing:.5px;color:var(--muted)}.session-bar{display:flex;align-items:center;gap:15px;padding:16px 0;border-top:1px solid var(--line);border-bottom:1px solid var(--line);font-size:12px;line-height:1.5}.session-bar>div{display:flex;align-items:center;gap:9px;flex:1}.dot{width:7px;height:7px;border-radius:50%;background:var(--forest);flex-shrink:0}#overallProgress{color:var(--muted)}.trails{display:grid;grid-template-columns:repeat(3,1fr);gap:12px;margin:30px 0}.trails button{background:transparent;border:1px solid var(--line);border-radius:12px;display:flex;align-items:center;gap:12px;text-align:left;padding:20px 16px;color:var(--ink);font-size:15px;min-height:92px}.trails button.selected{background:var(--forest);color:white;border-color:var(--forest)}.trail-number{font:27px var(--serif);opacity:.7}.trails button>span:nth-child(2){flex:1}.trails small{display:block;font-size:9px;letter-spacing:1px;margin-bottom:7px}.workspace{border:1px solid var(--line);border-radius:18px;background:var(--paper);overflow:hidden;scroll-margin-top:18px}.workspace-top{display:flex;align-items:center;justify-content:space-between;gap:10px;padding:30px 32px 22px}.workspace-top h2{font:31px var(--serif);margin:0}.workspace-top .eyebrow{margin-bottom:8px}.modes{display:grid;grid-template-columns:repeat(4,1fr);padding:0 32px;border-bottom:1px solid var(--line);gap:16px}.modes button{border:0;border-bottom:3px solid transparent;background:none;color:var(--muted);padding:13px 4px 17px;text-align:left;font-size:16px}.modes button[aria-pressed=true]{border-color:var(--forest);color:var(--forest)}.modes span{display:block;font-size:11px;margin-top:5px}#panel{padding:30px 32px;min-height:430px}.learn-grid{display:grid;grid-template-columns:1fr 1fr;gap:28px}.learn-copy h3{font:28px var(--serif);line-height:1.2}.learn-copy p{font-size:15px;color:var(--muted)}.fact{padding:14px 18px;background:var(--cream);border-radius:8px;margin:12px 0;font-size:14px;line-height:1.65}.fact small{display:block;color:var(--muted);margin-top:5px}.model{background:#f0f5ed;border:1px solid #dce8d7;border-radius:12px;padding:22px;min-width:0}.model h3{font:23px var(--serif)}.model svg{width:100%;max-height:310px;display:block;margin:15px auto}.model label{display:block;font-size:13px;margin:13px 0 7px}.model input[type=range]{width:100%;accent-color:var(--forest)}.model select{width:100%;padding:9px;background:#fff;border:1px solid #b4c5b6;border-radius:6px}.model-output{font-size:17px;margin:15px 0 0;color:var(--forest);line-height:1.6}.button-row{display:flex;gap:10px;flex-wrap:wrap;margin-top:22px}.primary,.secondary,.option{border:1px solid var(--forest);border-radius:8px;padding:12px 18px;min-height:45px;font-size:14px}.primary{background:var(--forest);color:white}.secondary{background:white;color:var(--forest)}.vocab{display:flex;flex-wrap:wrap;gap:8px;margin:22px 0}.vocab span{border:1px solid var(--line);padding:7px 10px;border-radius:7px;font-size:12px}.micro{font-size:12px!important;color:var(--muted)}.activity-layout{display:grid;grid-template-columns:230px 1fr;gap:28px}.activity-list{max-height:630px;overflow:auto;display:flex;flex-direction:column;gap:6px;padding:0 10px 10px 0}.activity-list button{border:1px solid transparent;border-radius:7px;background:var(--cream);color:var(--ink);text-align:left;padding:11px 12px;line-height:1.45;font-size:12px}.activity-list button.current{border-color:var(--forest);background:var(--green)}.activity-list small{display:block;color:var(--muted);font-size:10px;margin-bottom:4px}.activity-card{min-width:0}.activity-card h3{font:28px var(--serif);margin-bottom:15px;line-height:1.2}.activity-card .prompt{font-size:17px}.question-meta{font-size:11px;letter-spacing:1px;color:var(--muted);margin-bottom:13px}.options{display:grid;grid-template-columns:1fr 1fr;gap:10px;margin:20px 0}.option{background:white;text-align:left;color:var(--ink);border-color:var(--line)}.option[aria-pressed=true]{border-color:var(--forest);background:var(--green)}.answer-row{display:flex;align-items:center;flex-wrap:wrap;gap:10px;margin:22px 0}.answer-row label{flex-basis:100%;font-size:13px}.answer-row input{padding:12px;width:180px;max-width:100%;border:1px solid #93a797;border-radius:7px;font-size:20px}.answer-row .unit{color:var(--muted)}.feedback{padding:15px 17px;border-radius:8px;background:var(--cream);font-size:14px;line-height:1.65;margin:18px 0}.feedback.correct{background:#e5f2e6;border-left:3px solid var(--forest)}.feedback.retry{background:#fff3d8;border-left:3px solid #c8912d}.hint{background:#f7f6eb;padding:12px 16px;border-radius:8px;font-size:14px;line-height:1.6;margin:15px 0}.hint summary{cursor:pointer;color:var(--forest)}.hint p{margin:12px 0 0}.question-visual{background:#f5f7f1;border:1px solid var(--line);border-radius:10px;padding:15px;margin:15px 0}.question-visual svg{width:100%;max-height:280px;display:block}.question-visual p{font-size:13px;margin:0}.lab-select{display:flex;flex-wrap:wrap;gap:8px;margin-bottom:22px}.lab-select button{border-radius:20px;background:white;color:var(--forest);padding:8px 15px;border:1px solid var(--line);font-size:12px}.lab-select button.selected{background:var(--green);border-color:var(--forest)}.tile-grid{display:grid;grid-template-columns:repeat(10,1fr);max-width:400px;margin:18px auto;background:white;border:1px solid #9bb19f}.tile-grid button{aspect-ratio:1;border:1px solid #bcccbc;background:white;padding:0;min-width:0;color:var(--forest);font-size:14px}.tile-grid button.filled{background:#88b49a;color:#123e2d}.tile-grid button.half{background:linear-gradient(135deg,#88b49a 50%,white 50%)}.tile-grid button:focus-visible{z-index:1;outline-offset:-3px}.metric-strip{display:flex;gap:12px;flex-wrap:wrap}.metric-strip div{flex:1;background:white;border:1px solid var(--line);padding:12px;border-radius:8px;min-width:100px}.metric-strip span{display:block;font:28px var(--serif);margin-bottom:4px}.metric-strip small{font-size:11px;color:var(--muted)}.mission{border-left:3px solid var(--gold);padding:12px 16px;background:#fff8e9;margin:15px 0;font-size:14px;line-height:1.65}.steps{padding-left:20px;line-height:1.8;font-size:15px}.steps li{margin-bottom:9px}.checklist{display:grid;gap:10px;font-size:14px;line-height:1.5}.checklist label{display:flex;gap:10px;align-items:flex-start}.checklist input{accent-color:var(--forest);width:18px;height:18px;flex-shrink:0;margin-top:2px}.journal{width:100%;min-height:100px;border:1px solid #a7bca9;padding:12px;border-radius:7px;resize:vertical}.journey-note{display:flex;align-items:center;gap:20px;padding:35px 0}.note-icon{font-size:43px;color:#95712c}.journey-note h2{font:23px var(--serif);margin-bottom:7px}.journey-note p{font-size:13px;color:var(--muted);margin:0}.journey-note>a{font-size:12px;margin-left:auto;white-space:nowrap}#coverage{border:1px solid var(--line);padding:18px 22px;border-radius:12px;margin:0 0 35px;font-size:14px}#coverage summary{cursor:pointer}#coverageContent{padding-top:20px;line-height:1.7}#coverageContent table{border-collapse:collapse;width:100%;font-size:13px}th,td{text-align:left;padding:11px 8px;border-bottom:1px solid var(--line);font-weight:400;vertical-align:top}.table-scroll{overflow:auto}footer{border-top:1px solid var(--line);padding:28px 44px 40px;display:grid;grid-template-columns:160px 1fr;gap:10px 28px}footer .brand{font-size:24px;align-self:start}footer p,footer>a:last-child{font-size:11px;color:var(--muted);line-height:1.6;margin:0}footer p:nth-child(3){grid-column:2}.skip{position:absolute;left:20px;top:-80px;z-index:20;background:#fff;padding:12px}.skip:focus{top:12px}.empty{padding:25px;background:var(--cream);border-radius:10px}.check-summary{padding:24px;background:var(--cream);border-radius:12px}.check-summary h3{font:30px var(--serif)}.check-summary .big{font:50px var(--serif);color:var(--forest)}.noscript{padding:20px}button:hover:not(:disabled){filter:brightness(.97)}[hidden]{display:none!important}.shape-cards{display:grid;grid-template-columns:repeat(2,1fr);gap:10px}.shape-cards svg{height:115px;margin:0}.shape-cards p{font-size:12px;text-align:center}.group-title{font-size:13px;color:var(--forest);margin:22px 0 10px}
@media(max-width:850px){header{padding:20px 24px}main{padding:0 24px}.hero{gap:15px;padding:35px 0}.hero-copy{min-width:0}.hero-chips span:last-child{display:none}.trails button{padding:14px 10px;gap:8px;font-size:13px}.trail-number{font-size:22px}.trails small{font-size:8px;letter-spacing:.4px}.workspace-top{padding:24px}.modes{padding:0 24px}#panel{padding:24px}.activity-layout{grid-template-columns:180px 1fr;gap:20px}.journey-note{flex-wrap:wrap}.journey-note>a{margin-left:63px}footer{padding:24px}}
@media(max-width:600px){header{padding:17px 18px}.brand{font-size:23px}.grade{font-size:9px;margin-left:3px;padding-left:10px}.back{font-size:11px}.back span{margin-left:3px}main{padding:0 16px}.hero{grid-template-columns:1fr;padding:30px 4px 26px;gap:10px}h1{font-size:42px;letter-spacing:-1px}.hero-art{display:none}.subtitle{font-size:17px}.intro{font-size:14px}.hero-chips{margin-top:18px}.session-bar{flex-wrap:wrap;padding:12px 4px;gap:6px 12px}.session-bar>div{flex-basis:75%}#overallProgress{margin-left:16px}.trails{gap:7px;margin:20px 0}.trails button{flex-direction:column;align-items:flex-start;gap:6px;padding:12px 9px;font-size:12px;line-height:1.45;min-height:120px}.trails button>span:last-child{display:none}.trails small{line-height:1.5;font-size:8px}.trail-number{font-size:20px}.workspace{border-radius:12px}.workspace-top{padding:20px 17px}.workspace-top h2{font-size:26px}.workspace-top .eyebrow{font-size:9px;letter-spacing:1.2px}.count-pill{font-size:10px;padding:6px 8px;max-width:94px;text-align:center}.modes{padding:0 14px;gap:8px}.modes button{font-size:14px;padding:10px 1px 12px}.modes span{font-size:9px;line-height:1.5}#panel{padding:20px 17px}.learn-grid{grid-template-columns:1fr;gap:16px}.learn-copy h3,.activity-card h3{font-size:25px}.activity-layout{display:flex;flex-direction:column;gap:20px}.activity-list{flex-direction:row;max-height:none;overflow-x:auto;padding:0 0 10px;max-width:100%}.activity-list button{min-width:160px;max-width:190px}.activity-card .prompt{font-size:16px}.options{grid-template-columns:1fr}.model{padding:17px}.journey-note{gap:13px;padding:26px 3px}.journey-note>div{flex:1}.journey-note h2{font-size:21px}.journey-note>a{margin-left:53px}.note-icon{font-size:35px}#coverage{padding:16px}.metric-strip div{min-width:82px;padding:9px}.metric-strip span{font-size:23px}.metric-strip small{font-size:10px}.tile-grid button{font-size:11px}footer{display:block;padding:24px 20px}footer p{margin:15px 0}footer .brand{display:block}th,td{padding:9px 6px}.primary,.secondary{padding:11px 14px}}
@media(prefers-reduced-motion:reduce){*{scroll-behavior:auto!important;animation:none!important;transition:none!important}}
@media print{header,.hero-art,.trails,.modes,.session-bar,.activity-list,.button-row,footer{display:none}main{padding:0}.workspace{border:none}#panel{padding:0}.learn-grid{display:block}.model{break-inside:avoid}.hero{padding:0}h1{font-size:28px}}
.record-table input{width:150px;max-width:100%;padding:9px;border:1px solid #a8baa9;border-radius:5px}.record-table{margin:14px 0}.record-table th{min-width:150px}.record-table input:focus{background:#fffdec}