:root{--paper:#faf6ed;--ink:#492231;--text:#332e2b;--muted:#776c65;--line:#ded4c7;--panel:#fffdf7;--green:#2c6848;--green-soft:#e0efdf;--blue:#285c85;--blue-soft:#dfeaf5;--purple:#69547e;--purple-soft:#ece3f0;--amber:#825722;--amber-soft:#f6ecd7;font-family:Arial,'PingFang SC','Microsoft YaHei',system-ui,sans-serif;color:var(--text);background:var(--paper);line-height:1.7}*{box-sizing:border-box}body{margin:0}button,a{-webkit-tap-highlight-color:transparent}button{font:inherit;cursor:pointer}button:focus-visible,a:focus-visible,.drop-zone:focus-visible,summary:focus-visible{outline:3px solid #a17a99;outline-offset:4px}button:disabled{cursor:default;opacity:.6}a{color:inherit;text-decoration:none}h1,h2,h3,p,dl,dd{margin:0}h1,h2,h3{color:var(--ink);font-weight:500}h1{font-family:Georgia,'Songti SC','SimSun',serif;font-size:clamp(36px,4.6vw,62px);line-height:1.3;letter-spacing:-.045em}h2{font-size:20px;line-height:1.45}h3{font-size:22px;line-height:1.5}.lab-header,main,footer{width:min(1280px,calc(100% - 80px));margin:auto}.lab-header{display:flex;justify-content:space-between;align-items:center;gap:25px;height:92px;border-bottom:1px solid var(--line)}.lab-brand{font:29px Georgia,serif;letter-spacing:-1px;color:var(--ink);white-space:nowrap}.lab-brand>span{font:10px Arial,sans-serif;letter-spacing:2px;margin-left:16px;color:var(--muted)}.header-right{display:flex;gap:25px;align-items:center;font-size:12px}.language-switch{display:flex;gap:3px;padding:3px;border:1px solid var(--line);border-radius:30px}.language-switch button{border:0;background:none;padding:6px 10px;font-size:11px;border-radius:20px;color:var(--muted)}.language-switch button[aria-pressed=true]{background:var(--ink);color:var(--paper)}.intro{padding:50px 0 26px}.eyebrow{font-size:11px;letter-spacing:1.4px;color:var(--muted);margin-bottom:16px}.intro-copy{font-size:15px;color:var(--muted);margin-top:18px;line-height:1.85}.mode-tabs{display:flex;gap:10px;flex-wrap:wrap;margin-top:30px}.mode-tabs button{border:1px solid var(--line);background:transparent;padding:12px 21px;border-radius:30px;color:var(--muted);font-size:13px;min-height:45px}.mode-tabs button[aria-selected=true]{background:var(--ink);border-color:var(--ink);color:var(--paper)}.experiment-toolbar{display:flex;align-items:center;justify-content:space-between;gap:25px;padding:17px 0;border-top:1px solid var(--line)}.experiment-toolbar>p{font-size:15px;font-weight:500}.toolbar-actions{display:flex;gap:8px;flex:0 0 auto}.toolbar-actions button,.section-heading>button{font-size:11px;border:1px solid #cec2b4;border-radius:20px;background:transparent;color:var(--ink);padding:9px 15px;min-height:38px}.toolbar-actions button:hover,.section-heading>button:hover{background:#eee5dd}.workbench{display:grid;grid-template-columns:.85fr 1.15fr 1fr;gap:20px;align-items:stretch}.card-library,.composition-panel,.result-panel{min-width:0;border:1px solid var(--line);border-radius:10px;padding:23px;background:var(--panel)}.panel-heading{display:flex;align-items:baseline;gap:10px;margin-bottom:18px}.panel-heading h2{font-size:17px}.step-number{font:11px Georgia,serif;color:var(--muted)}.help{font-size:12px;color:var(--muted);line-height:1.85;margin-bottom:20px}.card-pool{display:grid;gap:13px}.context-card{position:relative;display:flex;flex-direction:column;align-items:flex-start;min-height:114px;text-align:left;border:1px solid #d4d4ca;border-radius:9px;padding:18px;background:#eff1e7;color:var(--text);cursor:grab;touch-action:none;transition:transform .2s,box-shadow .2s,border-color .2s}.context-card strong{font-size:21px;font-weight:500;line-height:1.4}.context-card small{font-size:11px;margin-top:8px;color:var(--muted)}.context-card[data-tone=green]{background:var(--green-soft);border-color:#c1d5be}.context-card[data-tone=green] strong{color:var(--green)}.context-card[data-tone=blue]{background:var(--blue-soft);border-color:#bed1df}.context-card[data-tone=blue] strong{color:var(--blue)}.context-card[data-tone=purple]{background:var(--purple-soft);border-color:#d6c5df}.context-card[data-tone=purple] strong{color:var(--purple)}.context-card[data-tone=wine]{background:#eedee4;border-color:#dcc1cb}.context-card[data-tone=wine] strong{color:var(--ink)}.context-card[aria-pressed=true]{box-shadow:inset 0 0 0 2px currentColor;transform:translateX(3px)}.context-card:active{cursor:grabbing}.context-card.is-dragging{opacity:.45}.predict-prompt{border-top:1px solid var(--line);padding-top:18px;margin-top:22px;font-size:12px;line-height:1.85;color:var(--muted)}.selection-count{font-size:10px;color:var(--muted);margin-left:auto}.drop-zone{position:relative;display:flex;flex-direction:column;align-items:center;justify-content:center;min-height:310px;border:1px dashed #bfb5a8;border-radius:9px;background:#f1ede2;padding:25px 20px;transition:background .2s,border-color .2s}.drop-zone.drag-over{background:#e7ecd9;border-color:#6c8049;box-shadow:inset 0 0 0 2px #8fa06f}.concept-tile{display:flex;flex-direction:column;align-items:center;justify-content:center;padding:24px 20px;min-height:180px;width:90%;max-width:235px;background:#fffdf7;border:1px solid #d8cec1;border-radius:10px;box-shadow:0 9px 18px #503c2920;transform:rotate(-3deg);position:relative;z-index:1;transition:transform .3s}.concept-tile strong{font:44px/1.2 Georgia,serif;color:#292927;margin:17px 0 13px;letter-spacing:-1px}.concept-tile p{font-size:11px;color:var(--muted);text-align:center}.tile-label{letter-spacing:1px}.overlay-tray{display:flex;flex-wrap:wrap;justify-content:center;gap:7px;width:100%;position:relative;z-index:2;margin-top:-21px;min-height:30px}.domain-overlay{border:1px solid #c5cdbb;border-radius:7px;padding:12px 15px;font-size:13px;background:#e4ebddec;box-shadow:0 4px 12px #3c483218;animation:place-card .28s ease-out;transform:rotate(2deg)}.domain-overlay[data-tone=green]{color:var(--green);background:#d8eacdf2}.domain-overlay[data-tone=blue]{color:var(--blue);background:#d8e7f4f2}.domain-overlay[data-tone=purple]{color:var(--purple);background:#e9deeff2}.domain-overlay[data-tone=wine]{color:var(--ink);background:#ecd8e1f2}.domain-overlay:nth-child(2){transform:rotate(-2deg)}.drop-help{font-size:11px;color:#84776b;margin-top:18px;text-align:center}.selected-cards{display:flex;flex-wrap:wrap;gap:8px;min-height:35px;margin-top:17px}.selected-chip{border:1px solid var(--line);border-radius:25px;background:#fffdf7;color:var(--muted);font-size:11px;padding:8px 12px;min-height:35px}.selected-chip:hover{border-color:var(--ink);color:var(--ink)}.selected-chip span{margin-left:10px}.result-panel{display:flex;flex-direction:column;align-items:flex-start;transition:background .3s}.result-state{font-size:11px;color:var(--muted);border-bottom:1px solid var(--line);padding-bottom:12px;width:100%}.result-panel>h3{font-size:28px;line-height:1.35;margin:22px 0 15px}.result-panel>p#meaning-explanation{font-size:13px;line-height:1.9;color:var(--muted)}#fruit-image{width:150px;height:150px;object-fit:contain;align-self:center;margin:15px 0 -4px}.company-name{font:42px/1.1 Georgia,serif;color:var(--blue);padding:40px 0 17px;letter-spacing:-1.5px}.company-name span{display:block;font-size:24px;letter-spacing:0;margin-top:5px}.math-result{font:61px/1.2 Georgia,serif;letter-spacing:-2px;color:var(--purple);padding:35px 0 10px}.result-panel[data-tone=green]{background:#f2f8ed}.result-panel[data-tone=blue]{background:#eff5fa}.result-panel[data-tone=purple]{background:#f4eff7}.result-panel[data-tone=wine]{background:#f7eef2}.result-panel[data-tone=amber]{background:var(--amber-soft)}.result-panel[data-tone=amber] h3{color:var(--amber);font-size:24px}.demo-caption{font-size:10px;line-height:1.8;color:var(--muted);border-top:1px solid var(--line);padding-top:13px;margin-top:auto;width:100%}.result-panel #meaning-explanation+.demo-caption{margin-top:25px}.action-status{min-height:30px;font-size:12px;color:var(--muted);margin:16px 0}.grid-section{padding:30px 0 36px;border-top:1px solid var(--line)}.section-heading{display:flex;justify-content:space-between;align-items:end;gap:25px;margin-bottom:22px}.section-heading h2{font-size:26px}.section-heading .eyebrow{margin-bottom:12px}.section-heading>button{flex:0 0 auto}.four-grid{display:grid;grid-template-columns:1fr 1fr 1.3fr 1.3fr;border:1px solid var(--line);border-radius:8px;overflow:hidden}.four-grid>div{padding:21px;background:#fffdf7;min-width:0}.four-grid>div+div{border-left:1px solid var(--line)}.four-grid dt{font-size:12px;color:var(--muted);margin-bottom:14px}.four-grid dd{font-size:14px;line-height:1.85;overflow-wrap:anywhere}.four-grid .condition-cell{background:#eee5ef}.check-section{display:grid;grid-template-columns:1fr 1.5fr;gap:60px;border-top:1px solid var(--line);padding:36px 0}.check-intro h2{font-size:27px;line-height:1.5;max-width:350px}.check-intro>p:last-child{font-size:12px;color:var(--muted);line-height:1.85;margin-top:14px}.check-body h3{font-size:19px;line-height:1.7}.answer-options{display:flex;gap:9px;flex-wrap:wrap;margin-top:22px}.answer-options button{background:#fffdf7;border:1px solid var(--line);border-radius:25px;padding:11px 17px;min-height:44px;font-size:13px;color:var(--text)}.answer-options button[aria-pressed=true]{background:#ece3ea;border-color:#9f7d94}.answer-options button.is-correct{background:#e3efdF;border-color:#86a084;color:#2d5f3d}.check-feedback{min-height:47px;margin-top:18px;font-size:12px;color:var(--muted);line-height:1.85}.check-feedback.correct{color:var(--green)}.check-feedback.incorrect{color:#8a5137}.discussion{border-top:1px solid var(--line);padding:25px 0 36px;color:var(--muted);font-size:12px}.discussion summary{cursor:pointer;font-size:13px;color:var(--ink);padding:5px 0}.discussion ol{padding-left:20px;margin:18px 0}.discussion li{margin:10px 0}.discussion>p{font-size:11px;line-height:1.85;max-width:800px}.drag-ghost{position:fixed;z-index:100;pointer-events:none;opacity:.9;transform:translate(-50%,-50%) rotate(-3deg);width:180px;max-width:45vw;box-shadow:0 15px 30px #35252a2e}.drag-ghost small{display:none}footer{display:flex;justify-content:space-between;align-items:start;gap:25px;padding:23px 0 30px;border-top:1px solid var(--line);color:var(--muted);font-size:10px}footer p{line-height:1.9}footer a{text-decoration:underline;text-underline-offset:3px}[hidden]{display:none!important}.skip{position:absolute;left:-9999px}.skip:focus{left:15px;top:10px;background:#fff;padding:10px;z-index:200}noscript{display:block;text-align:center;padding:30px}@keyframes place-card{from{opacity:.2;translate:0 -16px}to{opacity:1;translate:0 0}}
@media(max-width:1000px){.lab-header,main,footer{width:calc(100% - 50px)}.workbench{grid-template-columns:.9fr 1.1fr}.result-panel{grid-column:1/-1;display:grid;grid-template-columns:1fr 1.3fr;gap:10px 30px;align-items:start}.result-panel .panel-heading{grid-column:1/-1;margin-bottom:5px}.result-state{grid-column:1/-1}.result-panel>h3{grid-column:2;margin:17px 0 0}.result-panel>#meaning-explanation{grid-column:2}.result-panel>.demo-caption{grid-column:1/-1;margin-top:12px!important}.result-panel #fruit-image,.result-panel #company-visual,.result-panel #math-result{grid-column:1;grid-row:3/5;justify-self:center;align-self:center;padding-top:15px;margin:0}.check-section{gap:35px;grid-template-columns:1fr 1.5fr}}
@media(max-width:600px){.lab-header,main,footer{width:calc(100% - 32px)}.lab-header{height:78px;gap:12px}.lab-brand{font-size:24px}.lab-brand>span{display:none}.header-right{gap:12px}.header-right>a{font-size:10px}.language-switch button{padding:5px 8px}.intro{padding:32px 0 22px}.intro .eyebrow{font-size:10px}.intro-copy{font-size:13px;margin-top:17px}.mode-tabs{gap:8px;margin-top:23px}.mode-tabs button{font-size:11px;padding:11px 14px}.experiment-toolbar{align-items:start;gap:15px}.experiment-toolbar>p{font-size:13px}.toolbar-actions{gap:6px}.toolbar-actions button{font-size:10px;padding:8px 11px;white-space:nowrap}.workbench{grid-template-columns:1fr;gap:15px}.card-library,.composition-panel,.result-panel{padding:19px}.card-pool{grid-template-columns:1fr 1fr;gap:12px}.context-card{padding:15px 12px;min-height:104px}.context-card strong{font-size:19px}.context-card small{font-size:10px}.help{font-size:11px;margin-bottom:15px}.predict-prompt{margin-top:16px;padding-top:13px;font-size:11px}.panel-heading{margin-bottom:13px}.panel-heading h2{font-size:18px}.drop-zone{min-height:265px}.concept-tile{min-height:155px}.concept-tile strong{font-size:40px}.result-panel{display:flex;grid-column:auto;gap:0}.result-panel>h3{margin:18px 0 12px;font-size:27px}.result-panel #fruit-image{margin:14px 0 -5px;width:140px;height:140px}.result-panel #company-visual{padding:27px 0 12px;font-size:38px}.result-panel #math-result{padding:26px 0 10px;font-size:55px}.result-panel>#meaning-explanation{font-size:13px}.result-panel>.demo-caption{margin-top:20px!important}.action-status{font-size:11px;margin:14px 0;min-height:24px}.section-heading{align-items:start;gap:17px;flex-direction:column}.section-heading h2{font-size:25px}.grid-section{padding:25px 0 30px}.four-grid{grid-template-columns:1fr 1fr}.four-grid>div{padding:17px 14px}.four-grid>div:nth-child(3){border-left:0;border-top:1px solid var(--line)}.four-grid>div:nth-child(4){border-top:1px solid var(--line)}.four-grid dd{font-size:12px}.four-grid dt{font-size:11px;margin-bottom:10px}.check-section{grid-template-columns:1fr;gap:24px;padding:28px 0}.check-intro h2{font-size:25px}.check-body h3{font-size:18px}.answer-options button{font-size:12px;padding:11px 15px}.check-feedback{font-size:12px;min-height:45px}.discussion{padding-bottom:27px}footer{flex-direction:column;gap:10px;font-size:10px}.demo-caption{font-size:10px}}
@media(prefers-reduced-motion:reduce){*,*:before,*:after{animation:none!important;transition:none!important;scroll-behavior:auto!important}}