:root{--ink:#30233e;--purple:#62458c;--paper:#f5f1e8;--line:#d9cee5;--green:#12643f}*{box-sizing:border-box}body{margin:0;color:var(--ink);background:var(--paper);font:17px/1.55 system-ui,sans-serif}button,input{font:inherit}a{color:var(--purple)}header{background:#fff;border-bottom:1px solid var(--line);padding:18px max(20px,calc((100% - 1040px)/2));display:flex;justify-content:space-between;gap:16px;align-items:center}.brand{font-size:26px;font-weight:850;letter-spacing:-1px}.badge{border:1px solid var(--line);background:#f5effd;border-radius:30px;padding:4px 12px;font-size:13px;font-weight:750}main{max-width:1080px;padding:32px 20px 60px;margin:auto}.eyebrow{font-size:13px;letter-spacing:.1em;font-weight:800;text-transform:uppercase;color:var(--purple)}h1{font-size:clamp(32px,5vw,48px);line-height:1.12;letter-spacing:-1.5px;margin:12px 0}h2{font-size:26px;line-height:1.25}h3{font-size:19px}.lead{max-width:700px;font-size:19px;color:#5b4e65}.notice{padding:14px 18px;background:#fff8df;border:1px solid #b7a05a;border-radius:14px;font-size:15px}.instructions{display:grid;grid-template-columns:1fr 1fr;gap:20px;margin:26px 0}.panel{background:#fff;border:1px solid var(--line);border-radius:22px;padding:25px}.panel h2{margin:6px 0 16px}.panel ol{padding-left:24px}.panel li{margin:8px 0}.example{background:#f5effd;border-radius:14px;padding:16px}.example strong{color:var(--purple)}.math{font-size:21px;font-weight:750;font-variant-numeric:tabular-nums}.identity{max-width:540px;margin:26px 0}label{font-weight:650;display:block}input{display:block;margin-top:8px;width:100%;min-height:48px;padding:10px 12px;border:2px solid #9c8bac;border-radius:10px;background:white;color:var(--ink)}input:focus,button:focus-visible,a:focus-visible{outline:3px solid #d19015;outline-offset:3px}small,.hint{color:#605469;font-size:14px}.progress{display:flex;gap:12px;flex-wrap:wrap;justify-content:space-between;align-items:center;margin:26px 0 18px}.progress nav{display:flex;gap:16px;flex-wrap:wrap}.question-grid{display:grid;grid-template-columns:1fr 1fr;gap:16px}.question{background:white;border:1px solid var(--line);border-radius:18px;padding:20px;break-inside:avoid}.question .number{font-size:12px;letter-spacing:.05em;text-transform:uppercase;color:var(--purple);font-weight:800}.question label{margin:8px 0}.question .fraction{font-size:25px}.section-head{margin-top:36px}.actions{display:flex;gap:12px;flex-wrap:wrap;margin:24px 0}button{border:2px solid var(--purple);border-radius:12px;background:var(--purple);color:white;min-height:48px;padding:10px 20px;font-weight:750;cursor:pointer}button.secondary{background:white;color:var(--purple)}button:disabled{opacity:.55;cursor:default}.feedback{font-size:15px;margin-top:12px}.correct{color:var(--green)}.incorrect{color:#a12d28}.question:has(.incorrect){border-color:#a12d28}.question:has(.correct){border-color:var(--green)}#error{color:#92201c;font-weight:700}#results{scroll-margin-top:15px}#result-title{outline:none}.score{font-size:38px;font-weight:850;color:var(--purple)}.table-wrap{overflow:auto}table{border-collapse:collapse;width:100%;font-size:14px}th,td{text-align:left;vertical-align:top;padding:10px;border-bottom:1px solid var(--line);overflow-wrap:anywhere}th{background:#f5effd}.footer{font-size:14px;color:#605469;margin-top:26px}[hidden]{display:none!important}.skip{position:absolute;left:15px;top:-100px;background:white;padding:10px;z-index:10}.skip:focus{top:10px}@media(max-width:660px){.instructions,.question-grid{grid-template-columns:1fr}main{padding:24px 16px}.panel{padding:20px}header{padding:14px 16px}.badge{font-size:11px}.actions button{width:100%}th,td{padding:8px}.math{font-size:19px}}@media print{body{background:white;font-size:11pt}header{padding:0 0 10px}main{padding:0;max-width:none}.notice,.actions,.progress,.skip,.footer,#error{display:none!important}.instructions{gap:12px}.panel,.question{border:1px solid #aaa;box-shadow:none;padding:12px}h1{font-size:26pt}h2{font-size:18pt}.lead{font-size:12pt}.question-grid{gap:8px}.question input{border:0;border-bottom:1px solid #555;border-radius:0;min-height:24px;padding:4px}.identity{margin:12px 0}body.has-report #activity,body.has-report #lesson{display:none}#results{border:0;padding:0}.table-wrap{overflow:visible}thead{display:table-header-group}tr{break-inside:avoid}th,td{font-size:9pt;padding:5px}.score{font-size:24pt}}

main{max-width:1060px;padding:18px 20px 30px}header{padding-top:10px;padding-bottom:10px}.activity-top{display:flex;justify-content:space-between;gap:16px;align-items:center}.activity-top h1{font-size:30px;margin:2px 0 12px;letter-spacing:-.7px}.activity-top .eyebrow{margin:0}.guide-actions{display:flex;gap:8px}.guide-actions button{font-size:14px;min-height:40px;padding:7px 12px}.compact{margin:0;padding:8px 12px;font-size:13px}.workbar{display:flex;gap:24px;align-items:center;justify-content:space-between;margin:12px 0}.identity{margin:0;width:360px}.identity label{font-size:14px}.identity input{min-height:40px;padding:6px 10px;margin-top:4px}.workbar p{margin:3px 0}.workspace{display:grid;grid-template-columns:minmax(0,1fr) 360px;gap:20px}.active-question{background:white;border:1px solid var(--line);border-radius:20px;padding:22px;display:flex;flex-direction:column;justify-content:space-between;min-height:330px}.question{padding:0;border:0;border-radius:0;background:none}.question label{font-size:25px;margin:18px 0}.question input{font-size:24px;max-width:100%;margin:16px 0 8px}.question .number{font-size:14px}.navigation{display:flex;justify-content:space-between;gap:12px;align-items:center;margin-top:24px}.navigation button{font-size:14px;padding:8px 12px;min-height:42px}.question-menu{background:#eee5f6;border:1px solid var(--line);border-radius:20px;padding:16px}.question-menu h2{font-size:17px;margin:0}.question-menu .hint{font-size:11px;margin:4px 0}.menu-label{font-size:12px;font-weight:750;margin:12px 0 6px}.menu-grid{display:grid;grid-template-columns:repeat(10,1fr);gap:4px}.menu-grid button{padding:2px;min-height:30px;font-size:12px;border:1px solid #ad9cbc;border-radius:6px;background:white;color:var(--ink)}.menu-grid button.answered{background:#62458c;color:white}.menu-grid button[aria-current=true]{outline:3px solid #a35b00;outline-offset:1px}.bottom-actions{display:flex;justify-content:space-between;align-items:center;gap:16px;margin-top:12px}.bottom-actions p{margin:0}.privacy{margin:8px 0 0;font-size:12px}.footer{font-size:11px;margin:14px 0 0}#error:empty{display:none}#error{font-size:14px}dialog{width:min(1000px,94vw);max-height:90vh;border:1px solid var(--line);border-radius:22px;background:var(--paper);color:var(--ink);padding:22px}dialog::backdrop{background:#24162d99}dialog h1{font-size:30px}dialog .instructions{margin-bottom:0}dialog .notice{display:none}#close-guide{float:right;position:sticky;top:0}#results{margin-top:24px}.score{font-size:28px;line-height:1.45}.fraction-bar{display:inline-block;vertical-align:middle;text-align:center;line-height:1.1;margin-right:8px}.fraction-bar span{display:block;padding:3px 8px}.fraction-bar span:first-child{border-bottom:2px solid currentColor}@media(max-width:800px){.workspace{grid-template-columns:minmax(0,1fr) 325px;gap:12px}.active-question{padding:16px}.question label{font-size:21px}.guide-actions button{font-size:12px}.question-menu{padding:12px}}@media(max-width:600px){.workspace{grid-template-columns:1fr}.activity-top{align-items:flex-start;flex-direction:column;gap:0}.guide-actions{margin-bottom:12px}.workbar{align-items:flex-start;flex-direction:column;gap:8px}.identity{width:100%}.menu-grid{grid-template-columns:repeat(10,1fr)}.menu-grid button{min-height:34px}.active-question{min-height:280px}.bottom-actions{flex-direction:column;align-items:stretch}.activity-top h1{font-size:28px}main{padding:16px}.question-menu{order:2}}@media print{header,.activity-top,.workbar,.workspace,.bottom-actions,.privacy{display:none!important}#results[hidden]{display:none!important}dialog{display:none!important}}
@media(min-width:801px) and (max-height:700px){header{padding-top:4px;padding-bottom:4px}.brand{font-size:22px}main{padding-top:10px}.activity-top h1{font-size:26px;margin-bottom:5px}.workbar{margin:8px 0}.workspace{gap:14px}.active-question{min-height:280px;padding:16px}.question label{margin:10px 0}.question input{margin:8px 0}.navigation{margin-top:12px}.question-menu{padding:12px}.menu-label{margin-top:8px}.menu-grid button{min-height:27px}.bottom-actions{margin-top:8px}.bottom-actions button{min-height:42px;padding:7px 16px}.privacy{font-size:11px}.footer{display:none}}

#access-panel{max-width:620px;margin:24px auto}.access-grid{display:grid;gap:12px}#save-status{font-weight:750;margin:6px 0}.save-error{color:#92201c}.teacher-tools{display:flex;gap:8px;flex-wrap:wrap}.teacher-tools button{font-size:14px}#teacher-panel{margin-top:20px}#teacher-panel .table-wrap{max-height:60vh}#teacher-message{white-space:pre-wrap}.recovery{overflow-wrap:anywhere}#recovery-token{font-family:monospace}#student-session{font-size:14px;display:flex;gap:10px;align-items:center;flex-wrap:wrap}#student-session button{min-height:30px;padding:3px 10px;font-size:12px}.teacher-detail{font-size:12px}.toolbar-status{display:flex;gap:10px;align-items:center;flex-wrap:wrap}@media print{body.teacher-print main>*,body.teacher-print header{display:none!important}body.teacher-print #teacher-panel{display:block!important}#teacher-panel .teacher-tools,#teacher-panel button{display:none!important}#teacher-panel .table-wrap{max-height:none;overflow:visible}}
/* Twenty-question multiple-choice edition. */
.question fieldset{padding:0;margin:10px 0;border:0}.question legend{font-size:22px;line-height:1.3;font-weight:750;margin-bottom:12px}.question label.choice{display:flex;align-items:center;gap:10px;font-size:17px;font-weight:650;border:1px solid #c9bbd7;background:#faf7ff;border-radius:10px;padding:9px 12px;margin:6px 0;cursor:pointer}.question label.choice:has(input:checked){border:2px solid #62458c;background:#eee5ff;padding:8px 11px}.question label.choice input{width:20px;height:20px;min-height:20px;margin:0;flex:none;accent-color:#62458c}.clear-answer{font-size:12px;min-height:28px;padding:3px 10px;margin-top:10px}.menu-grid{grid-template-columns:repeat(5,1fr);gap:8px}.menu-grid button{min-height:40px;font-size:15px}.question-menu{align-self:start}.instructions{grid-template-columns:1fr}.instructions .panel{max-width:720px;margin:auto}dialog{max-width:780px}.active-question{min-height:420px}.navigation{margin-top:14px}@media(min-width:801px) and (max-height:700px){.active-question{min-height:360px;padding:12px}.question legend{font-size:19px;margin-bottom:6px}.question label.choice{padding:5px 9px;margin:4px 0;font-size:16px}.question label.choice:has(input:checked){padding:4px 8px}.question fieldset{margin:6px 0}.clear-answer{margin-top:5px}.navigation{margin-top:8px}.menu-grid button{min-height:36px}}@media(max-width:600px){.question legend{font-size:20px}.question label.choice{font-size:16px}.active-question{min-height:400px}.menu-grid{grid-template-columns:repeat(5,1fr)}}
.name-teacher-row{display:flex;gap:12px;align-items:center}.name-teacher-row input{margin:0;min-width:0}.name-teacher-row button{min-height:48px}#student-session{justify-content:flex-start}#teacher-slot-active{margin-left:auto}#teacher-slot-active button{min-height:36px;font-size:14px;padding:4px 14px}#teacher-auth-dialog{max-width:480px}#teacher-auth-dialog input{margin-bottom:16px}#teacher-auth-dialog button{margin:4px 6px 4px 0}
@media(min-width:801px){.question label.choice{display:inline-flex;width:calc(50% - 6px);vertical-align:top;margin:4px 3px;min-height:60px;font-size:16px;padding:8px}.question label.choice:has(input:checked){padding:7px}.active-question{min-height:330px}.question legend{font-size:21px}.clear-answer{display:block;margin-top:7px}.question fieldset{margin:8px 0}.navigation{margin-top:10px}}
@media(min-width:801px) and (max-height:700px){.question label.choice{min-height:48px;padding:5px;font-size:15px}.question label.choice:has(input:checked){padding:4px}.active-question{min-height:300px}.question legend{font-size:18px}.clear-answer{margin-top:4px}}
/* Contextual visual helper replaces question navigation grid. */
.visual-helper{background:#eee5f6;border:1px solid var(--line);border-radius:20px;padding:16px;align-self:start}.visual-helper summary{font-size:18px;font-weight:800;cursor:pointer}.visual-helper h2{font-size:21px;margin:6px 0 10px}.visual-helper .eyebrow{font-size:10px;margin:12px 0 0}.visual-helper .hint{font-size:12px;margin:8px 0}.fraction-example{display:flex;gap:18px;align-items:center;margin:12px 0}.fraction-stack{font-size:30px;font-weight:800;line-height:1.1;text-align:center;min-width:45px}.fraction-stack span{display:block;padding:4px 9px}.fraction-stack span:first-child{border-bottom:2px solid currentColor;color:#62458c}.fraction-labels{font-size:13px;font-weight:700;display:grid;gap:14px}.calculator-example{border:1px solid #bba8ce;border-radius:12px;background:#fbf9ff;padding:10px;max-width:255px}.calculator-screen{text-align:right;background:#dce8d6;border:1px solid #9dac96;border-radius:5px;padding:4px 12px;font:700 25px/1.2 ui-monospace,monospace}.calculator-keys{display:flex;gap:8px;margin-top:8px}.calculator-keys span{display:block;flex:1;background:#ede7f4;border:1px solid #bba8ce;border-radius:5px;text-align:center;font-weight:800;padding:3px}.visual-steps{font-size:13px;padding-left:20px;margin:12px 0}.visual-steps li{margin:5px 0}.place-value-table{width:100%;table-layout:fixed;background:white;border-radius:8px;font-size:15px;font-variant-numeric:tabular-nums;margin:10px 0}.place-value-table th{font-size:9px;letter-spacing:-.3px;padding:6px 1px;text-align:center;overflow-wrap:normal}.place-value-table th:nth-child(2){width:15px}.place-value-table td{text-align:center;padding:7px 2px;font-weight:700}.place-value-table caption{font-size:12px;text-align:left;margin-bottom:5px}.place-emphasis{background:#eee5ff}.order-example{padding:10px 5px;background:white;border-radius:8px;font-size:17px;font-weight:800;text-align:center}.question-menu{display:none}@media(min-width:801px) and (max-height:700px){.visual-helper{padding:12px}.visual-helper h2{font-size:18px;margin-bottom:6px}.fraction-example{margin:7px 0}.fraction-stack{font-size:25px}.calculator-example{padding:7px}.visual-steps{margin:8px 0;font-size:12px}.visual-helper .hint{font-size:11px}.place-value-table td{padding:5px 2px}.place-value-table th{font-size:8px}.order-example{font-size:16px;padding:6px}}@media(max-width:600px){.visual-helper{order:2}.visual-helper summary{min-height:32px}.place-value-table th{font-size:9px}.visual-helper h2{font-size:20px}}
.helper-demo-row{display:grid;grid-template-columns:130px minmax(0,1fr);gap:10px;align-items:center;margin:10px 0}.helper-demo-row .fraction-example{gap:6px;margin:0}.helper-demo-row .fraction-stack{font-size:26px;min-width:30px}.helper-demo-row .fraction-stack span{padding:4px}.helper-demo-row .fraction-labels{font-size:10px;gap:13px}.helper-demo-row .calculator-example{padding:7px}.helper-demo-row .calculator-keys{gap:4px}.helper-demo-row .calculator-keys span{padding:2px;font-size:15px}.visual-helper p.visual-steps{padding-left:0;font-size:13px;margin:10px 0}.visual-helper h2{margin-bottom:8px}.visual-helper .hint{line-height:1.35}@media(min-width:801px) and (max-height:700px){.helper-demo-row{grid-template-columns:120px minmax(0,1fr);gap:6px;margin:7px 0}.helper-demo-row .fraction-labels{font-size:9px}.visual-helper p.visual-steps{font-size:12px;margin:8px 0}.visual-helper summary{font-size:16px}}
.place-value-table td{padding:3px 2px;line-height:1.3}.place-value-table th{padding:4px 1px;line-height:1.2}.place-value-table caption{font-size:11px;margin-bottom:4px}.order-example{padding:7px 3px;line-height:1.2}.visual-helper p.visual-steps{line-height:1.3;margin:8px 0}.helper-demo-row{grid-template-columns:140px minmax(0,1fr)}.helper-demo-row .fraction-labels{font-size:11px}@media(min-width:801px) and (max-height:700px){.place-value-table td{padding:2px;line-height:1.2}.place-value-table th{padding:3px 1px}.visual-helper .eyebrow{margin-top:8px}.visual-helper h2{line-height:1.15}.visual-helper .hint{margin:6px 0}.order-example{padding:5px 2px}}

/* Finish / helper placement revision: no question-bank or server change. */
.helper-column{min-width:0}.helper-column .guide-actions{display:flex;justify-content:center;margin-top:10px}.workbar{justify-content:flex-end}#finish-status:not(:empty){padding:10px 14px;border:1px solid #bda9d8;border-radius:10px;background:#f3edf9;font-weight:600}

/* Separate class-hour candidate. */
select{font:inherit;color:var(--ink);background:white;border:2px solid #9c8bac;border-radius:10px;min-height:42px;padding:7px 10px;max-width:100%}select:focus{outline:3px solid #d19015;outline-offset:3px}.name-teacher-row{align-items:end}.id-field{flex:1;min-width:0}.hour-field{flex:0 0 160px}.hour-field select{width:100%;margin-top:8px}.name-teacher-row label{font-size:14px}.teacher-filter{margin:12px 0}.teacher-filter label{display:inline;margin-right:10px}.hour-group th{background:#eee5f6;text-align:left;font-weight:800}@media(max-width:600px){.name-teacher-row{flex-wrap:wrap}.id-field{flex-basis:100%}.hour-field{flex:1}}