.alternating-lesson .shell{max-width:1210px}.alternating-lesson .lesson-nav{flex-wrap:wrap}.alternating-lesson .lesson-nav a{width:34px;min-height:36px}.alt-problem{padding:18px 23px;margin-bottom:16px;font-size:16px}.word-help{font-size:12px;color:var(--muted);margin-top:7px;line-height:1.7}.alt-question-line{margin-top:9px;padding-top:8px;border-top:1px solid var(--line);font-weight:600}.alt-layout{display:grid;grid-template-columns:minmax(0,1.15fr) minmax(0,1fr);gap:17px;align-items:start}.alt-model{grid-column:auto;grid-row:auto;min-width:0}.alt-work{padding:20px 23px;min-width:0}.alt-board{background:radial-gradient(ellipse at 50% 20%,#fffef5,#e9f2eb);border:1px solid #d3e1d6;border-radius:15px;overflow:hidden}.alt-board svg{display:block;width:100%;height:auto;max-height:480px;font-family:inherit}.alt-status{font-size:16px;font-weight:600;color:var(--deep);padding:10px 0 5px;min-height:43px;text-align:center}.alt-controls{display:flex;gap:9px;justify-content:center;flex-wrap:wrap}.alt-controls .primary{min-width:225px}.alt-note{font-size:13px;color:var(--muted);line-height:1.8;margin:9px 0}.alt-total-row{display:grid;grid-template-columns:1fr 1fr;gap:9px;margin-top:12px}.alt-total-row>div{display:flex;align-items:baseline;gap:7px;justify-content:center;border:1px solid #b9d3c5;border-radius:12px;padding:8px;background:#edf6ee;font-size:12px}.alt-total-row .total-b{background:#edf4fa;border-color:#c1d4e3}.alt-total-row b{font:500 28px Georgia,serif}.alt-views{border:0;border-top:1px solid var(--line);padding:10px 0 0;margin:14px 0 0;display:flex;gap:6px;flex-wrap:wrap}.alt-views legend{font-size:12px;color:var(--muted);padding-right:10px}.alt-views .btn{font-size:12px;padding:6px 9px}.alt-view-note{font-size:12px;line-height:1.7;color:var(--muted);min-height:40px;margin:7px 0}.alt-record h3{font-weight:600;font-size:15px;margin:9px 0}.alt-record table{width:100%;border-collapse:separate;border-spacing:0;table-layout:fixed;font-size:13px;text-align:center;border:1px solid var(--line);border-radius:10px;overflow:hidden}.alt-record th{background:#edf3ec;font-size:12px;font-weight:500;padding:7px 3px}.alt-record th:first-child{width:13%}.alt-record th:nth-child(2){width:21%}.alt-record th:nth-child(3){width:14%}.alt-record td{height:36px;padding:4px 3px;border-top:1px solid #e3eae3;font-variant-numeric:tabular-nums}.alt-record td:last-child{font-size:12px}.alt-record tr[data-person=A].taken{background:#ecf5ed}.alt-record tr[data-person=B].taken{background:#edf4f9}.alt-record tr.waiting{color:#8b9b92}.alt-record tr.current{outline:2px solid #b59a55;outline-offset:-2px}.person-chip{display:inline-block;min-width:21px;font-weight:700;color:#286657}.person-chip.blue{color:#356e94}.alt-question{margin-top:17px;padding-top:14px;border-top:1px solid var(--line)}.alt-question h3{font-size:15px;margin-bottom:8px;font-weight:600;line-height:1.8}.alt-question .memo-label{display:block;font-size:12px;color:var(--muted)}.alt-question textarea{display:block;width:100%;min-height:61px;resize:vertical;font-family:inherit;font-size:15px;line-height:1.75;color:var(--ink);border:1px solid #c3d4c9;border-radius:9px;background:#fffffc;padding:7px 10px;margin:4px 0 9px}.alt-question textarea:focus-visible{outline:3px solid #bc9144;outline-offset:2px}.alt-question .answer-line{flex-wrap:wrap;font-size:14px}.alt-question .answer-line input{width:85px}.alt-question .feedback{font-size:13px;min-height:25px;margin-top:6px;line-height:1.7}.alt-question .feedback.good{color:#266b54}.alt-question .feedback.wrong{color:#95612a}.alt-hint{margin-top:3px;font-size:13px;color:#637a69}.alt-hint summary{cursor:pointer;min-height:30px;display:list-item;color:#88632e}.alt-hint p{background:#fff8e7;padding:9px 11px;border-radius:9px;margin:3px 0 8px}.alt-check{font-size:13px;background:#edf5ee;padding:9px 11px;border-radius:9px}.alt-completion{font-size:14px;color:var(--deep);margin:12px 0}.alt-retry{margin-top:15px}.alt-model .model-top{flex-wrap:wrap}.ring-active{cursor:pointer}.ring-active:focus-visible{outline:none}.ring-active:focus-visible .stone-face,.ring-active:hover .stone-face{stroke:#b49141;stroke-width:2}.ring-removed{opacity:0;pointer-events:none}.ring-going{animation:ring-take .65s ease-in both;pointer-events:none;transform-origin:300px 234px}.ring-ghost{opacity:.1;pointer-events:none}.ring-show{opacity:1;pointer-events:none}.stone-face{transition:opacity .2s}.active-outline{fill:none;stroke:#bfa15e;stroke-width:1.5;stroke-dasharray:4 5;pointer-events:none}.alt-board text{fill:#47675c;font-size:16px}.alt-board .tray-letter{font-family:Georgia,serif;font-size:25px}.alt-board .tray-value{font-family:Georgia,serif;font-size:27px}.alt-board .board-note{font-size:14px}.alt-board .center-note{font-size:17px;fill:#906d30}.alt-question input[aria-invalid=true]{border-color:#b87a46;background:#fffbf2}.alt-question input[aria-invalid=false]{border-color:#72a58d}.alternating-lesson .btn{min-height:42px}.alternating-lesson .solution{margin-top:18px}.alternating-lesson .solution li+li{margin-top:14px}
@keyframes ring-take{0%{opacity:1;transform:translate(0,0) scale(1)}70%{opacity:.8}100%{opacity:0;transform:translate(var(--travel),0) scale(.09)}}
@media(max-width:820px){.alt-layout{grid-template-columns:1fr}.alt-model{max-width:680px;width:100%;margin:auto}.alt-work{padding:18px}.alt-problem{padding:16px 18px}.alt-record td:last-child{font-size:13px}.alt-board svg{max-height:500px}.alt-views{justify-content:center}}
@media(max-width:430px){.alternating-lesson .shell{width:calc(100% - 22px)}.alternating-lesson .page-title{gap:9px}.alternating-lesson .page-title h1{font-size:23px}.alternating-lesson .lesson-nav{gap:4px}.alternating-lesson .lesson-nav a{width:31px;font-size:12px}.alt-problem{font-size:15px}.alt-model{padding:13px 10px}.alt-model .model-top h2{font-size:14px}.alt-model .quiet-button{font-size:12px}.alt-total-row>div{gap:4px;font-size:11px}.alt-total-row b{font-size:25px}.alt-views .btn{padding:6px 7px;font-size:11px}.alt-record td:last-child{font-size:11px}.alt-status{font-size:15px}}
@media(prefers-reduced-motion:reduce){.ring-going{animation:none;opacity:0}.stone-face{transition:none}}
@media print{.top-nav,.lesson-nav,.alt-controls,.alt-views,.alt-view-note,.quiet-button,.alt-retry,.next-row,.answer-line button{display:none!important}.shell{width:100%!important}.alt-layout{display:block}.alt-model,.alt-work{break-inside:avoid;box-shadow:none}.alt-board svg{max-height:340px}.alt-work{margin-top:12px}.alt-question{break-inside:avoid}}