:root{--ink:#18211d;--muted:#64706a;--paper:#fff9e8;--board:#21483d;--board-light:#2f6657;--chalk:#f8f2d6;--sun:#f7c948;--coral:#f56e5a;--aqua:#2bb8a8;--blue:#4377d9;--shadow:#18211d2e;--radius:8px;--radius-sm:7px;--tap:44px;--sidebar-w:268px;--ease:cubic-bezier(.2, .8, .2, 1);--space-1:4px;--space-2:8px;--space-3:12px;--space-4:16px;--space-5:20px;--space-6:24px;--space-7:32px;--space-8:40px;--text-xs:.76rem;--text-sm:.82rem;--text-base:1rem;--text-md:1.15rem;--text-lg:1.5rem;--text-xl:2rem;--text-2xl:2.8rem;--leading-none:1;--leading-tight:1.35;--elev-press-dark:0 5px 0 #18211d38;--elev-press-mid:0 5px 0 #18211d2e;--elev-press-soft:0 5px 0 #18211d29;--dur-fast:.12s;--dur-base:.14s;--dur-slow:.26s}*{box-sizing:border-box}html{background:linear-gradient(90deg, #21483d14 1px, transparent 1px) 0 0 / 34px 34px, linear-gradient(#21483d0f 1px, transparent 1px) 0 0 / 34px 34px, var(--paper);min-height:100%;color:var(--ink);-webkit-text-size-adjust:100%;font-family:Avenir Next,Trebuchet MS,Verdana,sans-serif}body{min-height:100vh;margin:0}button,input{font:inherit}button{cursor:pointer}button:disabled{cursor:not-allowed;opacity:.55}.app{grid-template-columns:var(--sidebar-w) minmax(0, 1fr);min-height:100vh;transition:grid-template-columns var(--dur-slow) var(--ease);gap:18px;padding:18px;display:grid;position:relative}.app-status{grid-template-columns:1fr;place-items:center;font-weight:900}.panel{border-radius:var(--radius);box-shadow:0 16px 34px var(--shadow);background:#fff9e8db;border:2px solid #18211d1f}.sr-only{clip:rect(0, 0, 0, 0);white-space:nowrap;border:0;width:1px;height:1px;margin:-1px;padding:0;position:absolute;overflow:hidden}.app-kicker{letter-spacing:0;text-transform:uppercase;margin:0;font-size:.9rem;font-weight:900}.app-kicker a{color:var(--board);text-decoration:none}.app-kicker a:hover,.app-kicker a:focus-visible{text-decoration:underline;-webkit-text-decoration-color:var(--sun);text-decoration-color:var(--sun);text-underline-offset:3px;text-decoration-thickness:2px}.cta-pill{min-height:var(--tap);border-radius:var(--radius);transition:background var(--dur-fast) var(--ease), box-shadow var(--dur-fast) var(--ease), transform var(--dur-fast) var(--ease), border-color var(--dur-fast) var(--ease);justify-content:center;align-items:center;gap:8px;padding:10px 20px;font-size:clamp(1rem,2.4vw,1.2rem);font-weight:900;text-decoration:none;display:inline-flex;transform:translateY(0)}.cta-pill:hover,.cta-pill:focus-visible{outline:none;transform:translateY(2px)}.cta-pill-primary{border:1px solid var(--board);background:var(--board);color:var(--chalk);box-shadow:var(--elev-press-dark)}.cta-pill-primary:hover,.cta-pill-primary:focus-visible{background:var(--board-light);box-shadow:0 3px #18211d38}.cta-pill-ghost{border:2px solid var(--board);color:var(--board);box-shadow:var(--elev-press-soft);background:0 0}.cta-pill-ghost:hover,.cta-pill-ghost:focus-visible{border-color:var(--board);box-shadow:0 3px #18211d1a}.static-shell{opacity:0;max-width:780px;animation:static-shell-reveal .25s var(--ease) .4s forwards;justify-items:start;gap:14px;margin:0 auto;padding:clamp(40px,9vh,90px) 20px 48px;display:grid}@keyframes static-shell-reveal{to{opacity:1}}.static-kicker{color:var(--coral);letter-spacing:.12em;text-transform:uppercase;margin:0;font-size:.8rem;font-weight:900}.static-shell h1{margin:0;font-family:Georgia,Times New Roman,serif;font-size:clamp(2.1rem,6vw,3.6rem);line-height:1.02}.static-lede{max-width:56ch;color:var(--muted);margin:0;font-size:1.05rem;line-height:1.5}.static-nav ul{flex-wrap:wrap;gap:10px;margin:14px 0 0;padding:0;list-style:none;display:flex}.static-nav a{color:var(--ink);background:#fff9e8db;border:2px solid #18211d24;border-radius:999px;padding:10px 16px;font-size:.9rem;font-weight:800;text-decoration:none;display:inline-block}.static-nav a:hover,.static-nav a:focus-visible{background:var(--sun)}.level-mark{background:var(--sun);width:34px;height:34px;color:var(--ink);border-radius:50%;place-items:center;font-weight:800;display:grid}.sidebar{border-radius:var(--radius);height:calc(100vh - 36px);box-shadow:0 18px 38px var(--shadow);background:#fffdf5eb;border:1px solid #18211d1a;flex-direction:column;align-self:start;gap:10px;padding:12px;display:flex;position:sticky;top:18px;overflow:hidden}.sidebar-top{align-items:flex-start;gap:10px;margin-bottom:4px;display:flex}.sidebar-brand{min-width:0}.sidebar-brand h1{color:var(--board);margin:0;font-family:Georgia,Times New Roman,serif;font-size:1.5rem;line-height:1}.sidebar-brand a,.mobile-drawer-title a{color:inherit;text-decoration:none}.sidebar-brand a:hover,.sidebar-brand a:focus-visible,.mobile-drawer-title a:hover,.mobile-drawer-title a:focus-visible{color:var(--board-light);text-underline-offset:4px;outline:none;text-decoration:underline;text-decoration-thickness:2px}.level-list{scrollbar-color:#21483d61 transparent;flex-direction:column;flex:1;gap:7px;min-height:0;padding-right:2px;display:flex;overflow-y:auto}.level-item{border-radius:var(--radius-sm);transition:border-color .16s var(--ease), box-shadow .16s var(--ease);background:#fffdf5;border:1px solid #18211d1a;flex:none;overflow:hidden}.level-item.active{border-color:var(--board-light);box-shadow:inset 0 0 0 1px #2f665766}.level-heading{margin:0}.level-row{width:100%;min-height:58px;color:var(--ink);text-align:left;background:0 0;border:0;grid-template-columns:30px minmax(0,1fr) auto;align-items:center;gap:10px;padding:10px 12px 14px;display:grid;position:relative}.level-row:hover,.level-row:focus-visible{outline:none}.level-row .level-mark{border-radius:var(--radius-sm);background:var(--sun);width:30px;height:30px;color:var(--ink);font-weight:900}.level-item.active .level-mark{background:var(--board);color:var(--chalk)}.level-name{min-width:0;font-weight:800;line-height:1.1}.level-name small{color:var(--muted);text-overflow:ellipsis;white-space:nowrap;margin-top:2px;font-size:.7rem;font-weight:700;line-height:1.1;display:block;overflow:hidden}.level-bar{background:#21483d1f;border-radius:3px;height:6px;position:absolute;bottom:6px;left:12px;right:12px;overflow:hidden}.level-bar>i{border-radius:inherit;background:var(--aqua);height:100%;transition:width .32s var(--ease);display:block}.dot-grid{grid-template-columns:repeat(5,1fr);gap:5px;padding:4px 12px 12px;display:grid}.dot{aspect-ratio:1;border-radius:var(--radius-sm);color:#18211d80;min-width:0;transition:transform .14s var(--ease), background .14s var(--ease);background:#efe3bd;border:1px solid #18211d1f;place-items:center;font-size:.72rem;font-weight:800;display:grid}.dot:hover,.dot:focus-visible{outline:none;transform:translateY(-2px)}.dot.done{background:var(--aqua);border-color:var(--aqua);color:#06302b}.dot.current{background:var(--paper);border:2px solid var(--board);color:var(--board);box-shadow:none}.sidebar-reset-row{text-align:center;border-top:1px solid #18211d1a;flex:none;margin-top:auto;padding-top:10px}.sidebar-reset{min-height:34px;color:var(--muted);text-underline-offset:3px;cursor:pointer;background:0 0;border:0;padding:4px 10px;font-size:.78rem;font-weight:700;text-decoration:underline}.sidebar-reset:hover,.sidebar-reset:focus-visible{color:#a23d2e;outline:none}.confirm-backdrop{z-index:60;background:#18211d73;position:fixed;inset:0}.confirm-viewport{z-index:61;padding:var(--space-4);place-items:center;display:grid;position:fixed;inset:0}.confirm-popup{width:min(100%,380px);padding:var(--space-5) var(--space-5) var(--space-4);border:2px solid var(--board);border-radius:var(--radius);background:var(--paper);box-shadow:0 18px 40px #18211d59}.confirm-title{margin:0 0 var(--space-2);color:var(--ink);font-family:Georgia,Times New Roman,serif;font-size:var(--text-lg)}.confirm-copy{margin:0 0 var(--space-4);color:var(--muted);font-size:var(--text-sm);font-weight:600;line-height:var(--leading-tight)}.confirm-actions{justify-content:flex-end;gap:var(--space-2);display:flex}.confirm-keep,.confirm-erase{min-height:40px;font-size:var(--text-sm);cursor:pointer;border-radius:999px;padding:6px 14px;font-weight:800}.confirm-keep{border:2px solid var(--board);background:var(--board);color:var(--chalk)}.confirm-keep:hover,.confirm-keep:focus-visible{background:var(--board-light);outline:none}.confirm-erase{color:#a23d2e;background:0 0;border:2px solid #a23d2e80}.confirm-erase:hover,.confirm-erase:focus-visible{background:#f56e5a24;border-color:#a23d2e;outline:none}.mobile-levels,.mobile-drawer-backdrop,.mobile-drawer-viewport{display:none}.main{grid-template-rows:minmax(0,1fr) auto;gap:10px;min-width:0;min-height:calc(100vh - 36px);display:grid}.site-footer{color:#18211d94;text-align:center;font-size:.76rem;font-weight:800;line-height:1.35}.site-footer a{color:inherit;text-decoration:none}.site-footer a:hover,.site-footer a:focus-visible{text-decoration:underline}.board-wrap{align-items:stretch;min-height:0;display:grid}.board{border-radius:var(--radius);background:radial-gradient(circle at 16% 14%, #f7c9482e, transparent 20%), linear-gradient(135deg, #ffffff0f, transparent 32%), var(--board);min-height:620px;color:var(--chalk);box-shadow:inset 0 0 0 2px #fff9e82e, 0 22px 50px var(--shadow);border:10px solid #8a5d31;grid-template-rows:auto 1fr auto;gap:18px;padding:clamp(18px,3vw,34px);display:grid;position:relative;overflow:auto}.board:after{content:"";pointer-events:none;opacity:.28;background-image:linear-gradient(105deg,#0000 0 44%,#ffffff1f 45%,#0000 46% 100%),radial-gradient(circle at 60% 70%,#ffffff1f 0 1px,#0000 1.5px);background-size:100% 100%,18px 18px;position:absolute;inset:0}.board-head,.algebra-workspace,.target{z-index:1;position:relative}.board-head{flex-wrap:wrap;justify-content:space-between;align-items:center;gap:8px 16px;display:flex}.board h2{letter-spacing:0;text-wrap:balance;flex:auto;min-width:0;margin:0;font-family:Georgia,Times New Roman,serif;font-size:clamp(2rem,5vw,4.4rem);line-height:.96}.board-head-actions{flex:none;align-items:center;gap:10px;margin-left:auto;display:flex}.board-tips{min-height:42px;box-shadow:var(--elev-press-dark);color:var(--ink);transition:box-shadow var(--dur-base) var(--ease), transform var(--dur-base) var(--ease), background var(--dur-base) var(--ease);background:#fff3bd;border:2px solid #18211d2e;border-radius:999px;flex:none;align-items:center;gap:8px;padding:5px 12px 5px 7px;font-size:.82rem;font-weight:900;line-height:1;display:inline-flex;transform:scale(1)}.board-tips:hover,.board-tips:focus-visible{background:var(--sun);outline:none;transform:translateY(2px);box-shadow:0 3px #18211d38}.board-tips-glyph{background:var(--aqua);color:#fff9e8;border-radius:50%;place-items:center;width:28px;height:28px;font-size:1.1rem;line-height:1;display:inline-grid}.board-reset{color:#fff9e8b8;min-height:36px;transition:background var(--dur-base) var(--ease), color var(--dur-base) var(--ease), border-color var(--dur-base) var(--ease);background:0 0;border:1.5px solid #fff9e84d;border-radius:999px;flex:none;align-items:center;gap:6px;padding:4px 12px;font-size:.78rem;font-weight:800;line-height:1;display:inline-flex}.board-reset:hover,.board-reset:focus-visible{color:#ffd9d2;background:#f56e5a29;border-color:#f56e5a99;outline:none}.board-reset-glyph{font-size:1rem;line-height:1}.board-reset:disabled{cursor:not-allowed;opacity:.35}.board-reset:disabled:hover{color:#fff9e8b8;background:0 0;border-color:#fff9e84d}.board[data-mode=balanceScale] .equations,.board[data-mode=chooseParentheses] .equations{width:100%;max-width:680px;margin-inline:auto}.equations{align-content:center;gap:14px;padding:10px 0;display:grid}.equation{border-radius:var(--radius);background:#0b1c1847;border:1px solid #f8f2d629;grid-template-columns:minmax(0,1fr) auto;align-items:center;gap:14px;min-height:72px;padding:12px 16px;display:grid}.equation-left{word-break:keep-all;min-width:0;font-size:clamp(1.6rem,4vw,3.2rem);line-height:1.05}.equation-total{text-align:right;min-width:56px;color:var(--sun);font-size:clamp(1.8rem,4.5vw,3.5rem);font-weight:900}@property --workspace-density{syntax:"<number>";inherits:true;initial-value:1}@property --equation-scale{syntax:"<number>";inherits:true;initial-value:1}.algebra-workspace{--workspace-density:1;align-content:center;gap:calc(12px * var(--workspace-density));min-height:0;transition:--workspace-density .28s var(--ease);display:grid}.algebra-row-tools button{min-height:34px;font-weight:900}.algebra-list{gap:calc(12px * var(--workspace-density,1));display:grid}.derived-divider{min-height:calc(12px * var(--workspace-density,1));border-top:2px dashed #f8f2d657;margin:2px 4px}.algebra-equation{--equation-scale:calc(var(--row-fit-scale,1) * var(--workspace-density,1));min-height:calc(82px * var(--workspace-density,1));padding:calc(12px * var(--workspace-density,1));border-radius:var(--radius);background:#0b1c1847;border:1px solid #f8f2d629;grid-template-columns:minmax(0,1fr) auto;align-items:center;gap:8px 10px;transition:background .14s,border-color .14s,box-shadow .14s,opacity .14s;display:grid;position:relative}.algebra-equation.substitute-target{border-color:var(--sun);box-shadow:inset 0 0 0 1px #f7c94852}.algebra-row-tools{white-space:nowrap;flex-wrap:nowrap;justify-content:flex-end;align-items:center;gap:6px;min-width:0;display:flex}.algebra-equation.tools-wrapped{grid-template-columns:minmax(0,1fr)}.algebra-equation.tools-wrapped .algebra-row-tools{white-space:normal;flex-wrap:wrap;justify-content:flex-start}.algebra-row-tools .tool-chip{min-height:30px;color:var(--ink);transition:background .12s var(--ease), box-shadow .12s var(--ease), transform .12s var(--ease);background:#fff3bd;border:1px solid #18211d24;border-radius:999px;padding:0 12px;font-size:.78rem;line-height:1;transform:scale(1);box-shadow:0 3px #18211d33}.tool-label-compact,.algebra-equation.tools-compact .tool-label-full{display:none}.algebra-equation.tools-compact .tool-label-compact{display:inline}.algebra-row-tools .tool-chip:hover,.algebra-row-tools .tool-chip:focus-visible{background:var(--sun);outline:none;transform:translateY(1px);box-shadow:0 2px #18211d33}.algebra-row-tools .simplify-chip{background:#d9fff7}.delete-row-corner{z-index:2;color:#f8f2d69e;width:27px;height:27px;transition:background .12s var(--ease), border-color .12s var(--ease), color .12s var(--ease), transform .12s var(--ease);background:#f8f2d60f;border:1px solid #f8f2d629;border-radius:50%;place-items:center;padding:0;font-size:1rem;font-weight:900;line-height:1;display:grid;position:absolute;top:0;right:0;transform:translate(50%,-50%)}.delete-row-corner:hover,.delete-row-corner:focus-visible{color:#fff9e8;background:#f56e5a2e;border-color:#f56e5a9e;outline:none;transform:translate(50%,-50%)scale(1.05)}.scale-action{align-items:center;display:inline-flex}.algebra-expression{align-items:center;gap:calc(12px * var(--equation-scale));min-width:0;min-height:calc(68px * var(--equation-scale));flex-wrap:nowrap;display:flex}.algebra-side{align-items:center;gap:calc(10px * var(--equation-scale));min-width:0;min-height:calc(62px * var(--equation-scale));max-width:100%;padding:calc(4px * var(--equation-scale)) calc(6px * var(--equation-scale));border-radius:var(--radius);background:0 0;outline:1px dashed #0000;flex-wrap:nowrap;flex:0 auto;transition:background .12s,outline-color .12s,box-shadow .12s;display:flex}.algebra-side.drop-target{background:#f7c9481a;outline-color:#f7c94894}.algebra-side.drop-ready{outline-color:var(--sun);background:#f7c9482e;box-shadow:inset 0 0 0 1px #f7c94847}.algebra-equals{min-width:calc(46px * var(--equation-scale));min-height:calc(52px * var(--equation-scale));padding:0 calc(6px * var(--equation-scale));border-radius:var(--radius);color:var(--sun);font-size:clamp(calc(2rem * var(--equation-scale)), calc(3.4vw * var(--equation-scale)), calc(3.45rem * var(--equation-scale)));background:0 0;border:0;flex:none;place-items:center;font-weight:900;transition:background .14s,color .14s,transform .14s;display:grid}.algebra-equals:hover,.algebra-equals:focus-visible{color:#ffe07a;background:#f7c94824;outline:none;transform:scale(1.04)}.algebra-equals:active{transform:scale(.96)}.algebra-term{align-items:center;gap:calc(8px * var(--equation-scale));min-width:calc(58px * var(--equation-scale));min-height:calc(58px * var(--equation-scale));padding:calc(7px * var(--equation-scale)) calc(12px * var(--equation-scale));border-radius:var(--radius);color:var(--chalk);font-size:clamp(calc(1.55rem * var(--equation-scale)), calc(3.2vw * var(--equation-scale)), calc(3.45rem * var(--equation-scale)));touch-action:none;background:0 0;border:1px solid #0000;flex:none;justify-content:center;font-weight:900;display:inline-flex}.algebra-sortable-term{align-items:center;gap:calc(8px * var(--equation-scale));font-size:clamp(calc(1.55rem * var(--equation-scale)), calc(3.2vw * var(--equation-scale)), calc(3.45rem * var(--equation-scale)));white-space:nowrap;flex:none;display:inline-flex}.algebra-term>span,.drag-overlay-term{white-space:nowrap;align-items:center;gap:0;display:inline-flex}.equation-drag-preview{border-radius:var(--radius);max-width:min(720px,100vw - 32px);min-height:56px;color:var(--ink);white-space:nowrap;pointer-events:none;background:#fffdf5fa;border:1px solid #f8f2d659;align-items:center;gap:10px;padding:9px 12px;font-size:1.2rem;font-weight:900;display:inline-flex;box-shadow:0 14px 30px #00000047}.equation-drag-preview .preview-label{border-radius:var(--radius);background:#f7c9484d;flex:none;padding:5px 8px}.equation-drag-preview .preview-side{text-overflow:ellipsis;min-width:0;overflow:hidden}.equation-drag-preview .preview-equals{color:#b9912e;flex:none;font-size:1.45rem}.algebra-sortable-term.dragging{opacity:.24}.algebra-term:hover,.algebra-term:focus-visible{background:#fff9e81a;border-color:#f8f2d62e;outline:none}.algebra-term.substitute-target{background:#f7c9481a;border-color:#f7c9487a}.algebra-term.substitute-ready{border-color:var(--sun);background:#f7c94833;box-shadow:inset 0 0 0 1px #f7c9485c}.drag-overlay-term{border-radius:var(--radius);min-height:42px;color:var(--ink);cursor:grabbing;pointer-events:none;background:#fffdf5;border:1px solid #f8f2d659;padding:6px 10px;font-size:clamp(1.15rem,2.3vw,1.8rem);font-weight:900;box-shadow:0 14px 30px #00000047}.drag-overlay-term .term-sign{color:var(--board-light)}.drag-overlay-term-scale{display:inline-flex}.drag-overlay-term.game-term-overlay{min-width:calc(58px * var(--equation-scale,1));min-height:calc(58px * var(--equation-scale,1));gap:calc(8px * var(--equation-scale,1));padding:calc(7px * var(--equation-scale,1)) calc(12px * var(--equation-scale,1));font-size:clamp(calc(1.55rem * var(--equation-scale,1)), calc(3.2vw * var(--equation-scale,1)), calc(3.45rem * var(--equation-scale,1)))}@media (width<=900px){.drag-overlay-term.game-term-overlay{min-width:calc(38px * var(--equation-scale,1));min-height:calc(36px * var(--equation-scale,1));padding:calc(4px * var(--equation-scale,1)) calc(6px * var(--equation-scale,1));font-size:clamp(calc(1.2rem * var(--equation-scale,1)), calc(5vw * var(--equation-scale,1)), calc(1.65rem * var(--equation-scale,1)))}}.term-sign{color:var(--chalk);text-shadow:0 1px #0b1c18b3;flex:none;font-size:1.08em;font-weight:1000;line-height:1}.term-sign.prefix{width:calc(40px * var(--equation-scale));min-width:calc(40px * var(--equation-scale));min-height:calc(58px * var(--equation-scale));font-size:inherit;justify-content:center;align-items:center;display:inline-flex}.term-sign.prefix.empty{display:none}.algebra-side.sorting .term-sign.prefix{display:inline-flex}.algebra-side.sorting .term-sign.prefix.empty{display:none}.term-sign.prefix.combine-operator{width:calc(40px * var(--equation-scale));min-width:calc(40px * var(--equation-scale));height:calc(40px * var(--equation-scale));min-height:calc(40px * var(--equation-scale));color:#bffcf4;font:inherit;letter-spacing:0;text-shadow:0 1px #0b1c18b3;transition:background-color .14s var(--ease), border-color .14s var(--ease), box-shadow .14s var(--ease);background:#2bb8a829;border:1px solid #2bb8a89e;border-radius:50%;justify-content:center;align-items:center;padding:0;font-weight:1000;line-height:1;display:inline-flex}.term-sign.prefix.combine-operator:hover,.term-sign.prefix.combine-operator:focus-visible{border-color:var(--aqua);background:#2bb8a847;outline:none;box-shadow:0 0 0 2px #2bb8a829}.term-sign.prefix.combine-operator:active{background:#2bb8a85c;box-shadow:0 0 0 2px #2bb8a838}.term-sign.unary{margin-right:.28em}.empty-side{min-width:calc(58px * var(--equation-scale));min-height:calc(58px * var(--equation-scale));color:#f8f2d66b;font-size:clamp(calc(1.55rem * var(--equation-scale)), calc(3.2vw * var(--equation-scale)), calc(3.45rem * var(--equation-scale)));flex:none;justify-content:center;align-items:center;font-weight:900;line-height:1;display:inline-flex}.target{grid-template-columns:minmax(0,1fr) auto;align-items:center;gap:14px;display:grid}.algebra-equation.just-added{animation:derived-row-flash 1.6s var(--ease)}@keyframes 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#f7c9489e}.builder-clue-empty{color:#f8f2d680;font-size:clamp(1rem,2.6vw,1.3rem);font-style:italic;font-weight:800}.builder-clue-total{min-width:calc(56px * var(--equation-scale,1));text-align:right;color:var(--sun);font-size:clamp(calc(1.55rem * var(--equation-scale,1)), calc(3.2vw * var(--equation-scale,1)), calc(3.45rem * var(--equation-scale,1)));flex:none;font-weight:900;line-height:1}.builder-add-clue{min-height:var(--tap);border-radius:var(--radius);color:var(--chalk);cursor:pointer;transition:background var(--dur-fast) var(--ease), border-color var(--dur-fast) var(--ease);background:#f8f2d60f;border:2px dashed #f8f2d657;padding:10px 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strong{color:var(--board);font-size:1.15em}.builder-goal-secret{color:var(--coral);font-style:italic;font-weight:900;display:inline-block}.builder-goal-hint{max-width:none;color:var(--muted)}.builder-share{gap:clamp(16px,3vw,24px)}.builder-code-board{text-align:center;justify-items:center;gap:6px;min-height:0;padding:clamp(14px,3vw,22px) clamp(16px,4vw,28px);display:grid}.builder-code-label{color:#f8f2d6b3;text-transform:uppercase;letter-spacing:.18em;font-size:.82rem;font-weight:900}.builder-code{color:var(--sun);letter-spacing:.16em;font-family:Georgia,Times New Roman,serif;font-size:clamp(2.8rem,11vw,5rem);font-weight:900;line-height:1}.builder-share-link{gap:8px;display:grid}.builder-share-label{color:var(--board);text-transform:uppercase;letter-spacing:.03em;font-size:.86rem;font-weight:900}.builder-share-row{grid-template-columns:minmax(0,1fr) auto;align-items:stretch;gap:10px}.builder-share-input{height:auto;min-height:var(--tap);text-align:left;font-size:clamp(.9rem,2.4vw,1.05rem);font-weight:700}.builder-share-row .primary{white-space:nowrap;padding-inline:clamp(14px,3vw,22px)}.builder-send-actions{margin-top:clamp(4px,1.6vw,12px);display:flex}.builder-send-button{background:var(--coral);color:#fff9e8;min-width:clamp(190px,42vw,280px);box-shadow:0 6px 0 color-mix(in srgb, var(--coral) 52%, var(--ink));transition:transform var(--dur-fast) var(--ease), box-shadow var(--dur-fast) var(--ease), background var(--dur-fast) var(--ease);border:0;border-radius:999px;padding:clamp(15px,2.4vw,20px) clamp(30px,6vw,52px);font-size:clamp(1.1rem,2.6vw,1.4rem);font-weight:900}.builder-send-button:hover:not(:disabled),.builder-send-button:focus-visible:not(:disabled){box-shadow:0 4px 0 color-mix(in srgb, var(--coral) 52%, var(--ink));background:#ef6552;outline:none;transform:translateY(2px)}.builder-send-button:disabled{background:color-mix(in srgb, var(--board) 26%, var(--paper));color:color-mix(in srgb, var(--board) 55%, var(--paper));box-shadow:none}.builder-nav{justify-content:space-between;align-items:center;gap:24px;margin-top:clamp(10px,2.4vw,18px);display:flex}.builder-nav:has(>.primary:only-child){justify-content:flex-end}.builder-nav button:not(.primary){color:var(--board);background:0 0;border:0;border-radius:999px;padding:12px 16px;font-weight:900}.builder-nav button:not(.primary):hover,.builder-nav button:not(.primary):focus-visible{background:color-mix(in srgb, var(--board) 8%, transparent);outline:none}.builder-nav .primary{background:var(--coral);color:#fff9e8;width:auto;min-width:clamp(150px,32vw,210px);box-shadow:0 5px 0 color-mix(in srgb, var(--coral) 52%, var(--ink));transition:transform var(--dur-fast) var(--ease), box-shadow var(--dur-fast) var(--ease), background var(--dur-fast) var(--ease);border:0;border-radius:999px;padding:clamp(13px,2vw,17px) clamp(28px,5vw,44px);font-size:clamp(1.05rem,2.4vw,1.25rem);font-weight:900}.builder-nav .primary:hover:not(:disabled),.builder-nav .primary:focus-visible:not(:disabled){box-shadow:0 3px 0 color-mix(in srgb, var(--coral) 52%, var(--ink));background:#ef6552;outline:none;transform:translateY(2px)}.builder-nav .primary:disabled{background:var(--board);color:var(--chalk);opacity:.4;box-shadow:none}.builder-nav-hint{color:var(--muted);margin:0;font-size:.92rem;font-weight:800}@media (width<=900px){.builder-page{gap:20px;padding:20px 16px 40px}.builder-top{gap:8px;margin-bottom:-12px}.builder-title{font-size:clamp(26px,7vw,34px);line-height:1.05}.builder-set-card{min-height:148px}.builder-step-btn{width:50px;height:50px}.builder-clue-rows{gap:8px;padding:12px}.builder-clue-row.algebra-equation{min-height:60px}.builder-tile{min-width:58px;min-height:58px;font-size:clamp(2.1rem,9vw,2.8rem)}.builder-share-row{grid-template-columns:1fr}}.builder-term{align-items:center;gap:calc(4px * var(--equation-scale,1));display:inline-flex}.builder-sign-toggle{min-width:calc(40px * var(--equation-scale,1));color:var(--sun);font-size:clamp(calc(1.55rem * var(--equation-scale,1)), calc(3.2vw * var(--equation-scale,1)), calc(3.45rem * var(--equation-scale,1)));cursor:pointer;background:0 0;border:0;place-items:center;padding:0 2px;font-weight:900;line-height:1;display:inline-grid}.builder-sign-toggle:focus-visible{outline:2px solid var(--sun);outline-offset:2px;border-radius:8px}.builder-term-grip{cursor:grab;touch-action:none}.builder-term-grip:active{cursor:grabbing}.builder-term.dragging{opacity:.5}.builder-clue-row.drop-target{outline:2px dashed color-mix(in srgb, var(--sun) 60%, transparent);outline-offset:-4px}.builder-clue-row.drop-ready{outline:3px solid var(--sun);background:color-mix(in srgb, var(--sun) 12%, transparent)}.builder-palette.is-removing{border-radius:var(--radius);outline:2px dashed color-mix(in srgb, var(--coral) 55%, transparent);outline-offset:4px}.builder-palette.is-removing .builder-palette-hint{color:var(--coral)}.builder-palette.is-remove-ready{outline:3px solid var(--coral);background:color-mix(in srgb, var(--coral) 12%, transparent)}.builder-palette-hint.is-hidden,.builder-palette-tiles.is-hidden{visibility:hidden}.builder-palette-trash-msg{z-index:1;color:var(--coral);text-align:center;pointer-events:none;place-items:center;margin:0;padding:8px;font-size:clamp(1.05rem,3.4vw,1.5rem);font-weight:900;display:grid;position:absolute;inset:0}.drag-overlay-term.builder-term-overlay{font-size:clamp(calc(1.55rem * var(--equation-scale,1)), calc(3.2vw * var(--equation-scale,1)), calc(3.45rem * var(--equation-scale,1)))}@media (width<=900px){.builder-clue-total,.builder-sign-toggle{font-size:clamp(calc(1.2rem * var(--equation-scale,1)), calc(5vw * var(--equation-scale,1)), calc(1.65rem * var(--equation-scale,1)))}}.challenge-play{flex-direction:column;gap:clamp(16px,3vw,26px);width:min(900px,100%);min-height:100dvh;margin:0 auto;padding:clamp(20px,5vw,48px) clamp(16px,4vw,40px) clamp(28px,6vw,64px);display:flex}.challenge-play>.site-footer{margin-top:auto}.challenge-hero{gap:8px;display:grid}.challenge-hero h1{color:var(--board);margin:0;font-family:Georgia,Times New Roman,serif;font-size:clamp(1.8rem,5vw,3rem);line-height:1.02}.challenge-solved-banner{border-radius:var(--radius);background:color-mix(in srgb, var(--sun) 24%, var(--paper));border:2px solid color-mix(in srgb, var(--sun) 60%, transparent);color:var(--board);text-align:center;margin:0;padding:clamp(10px,2vw,16px) clamp(14px,3vw,22px);font-family:Georgia,Times New Roman,serif;font-size:clamp(1.3rem,3.4vw,2rem);font-weight:900}.challenge-solved-secondary{text-align:center;color:var(--ink);margin:0;font-weight:800}.challenge-missing-sub{color:var(--ink);margin:0;font-weight:700}.challenge-solved-action{background:var(--coral);border-color:var(--coral);color:#fff9e8;box-shadow:0 5px 0 color-mix(in srgb, var(--coral) 52%, var(--ink))}.challenge-missing{text-align:center;place-content:center}.challenge-missing h1{font-family:Georgia,Times New 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.my-challenges-headline{justify-items:center}.my-challenges-make{flex:none}.my-challenges-list{gap:clamp(10px,2vw,14px);margin:0;padding:0;list-style:none;display:grid}.my-challenge-card{gap:10px;padding:clamp(14px,2.6vw,20px) clamp(14px,3vw,22px);display:grid}.my-challenge-head{flex-wrap:wrap;align-items:center;gap:clamp(8px,2vw,14px);display:flex}.my-challenge-glyphs{gap:4px;font-size:clamp(1.4rem,4vw,2rem);display:inline-flex}.my-challenge-code{letter-spacing:.12em;color:var(--board);font-family:Georgia,Times New Roman,serif;font-weight:900}.my-challenge-date{color:var(--muted);white-space:nowrap;margin-left:auto;font-size:.85rem;font-weight:800}.my-challenge-stat{color:var(--ink);font-weight:800}.my-challenge-actions{flex-wrap:wrap;align-items:center;gap:8px;display:flex}.my-challenge-confirm{color:var(--board);font-weight:900}.my-challenge-action-status{color:var(--muted);margin:0;font-size:.88rem;font-weight:800;line-height:1.25}.my-challenge-action-status.warn{color:var(--coral)}.my-challenge-share-url{color:var(--board);overflow-wrap:anywhere;margin-top:4px;display:block}.card-btn{border:2px solid var(--board);border-radius:var(--radius-sm);min-height:40px;color:var(--board);white-space:nowrap;transition:background .12s var(--ease), border-color .12s var(--ease), color .12s var(--ease), opacity .12s var(--ease);background:0 0;align-items:center;gap:6px;padding:0 16px;font-size:.92rem;font-weight:900;text-decoration:none;display:inline-flex}.card-btn:hover:not(:disabled),.card-btn:focus-visible:not(:disabled){background:#21483d1a;outline:none}.card-btn:disabled{opacity:.45;cursor:not-allowed}.card-btn-primary{background:var(--board);border-color:var(--board);color:var(--chalk)}.card-btn-primary:hover:not(:disabled),.card-btn-primary:focus-visible:not(:disabled){background:var(--board-light);border-color:var(--board-light);color:var(--chalk)}.card-btn-danger{border-color:var(--coral);color:var(--coral)}.card-btn-danger:hover:not(:disabled),.card-btn-danger:focus-visible:not(:disabled){background:#f56e5a1f}.my-challenges-pager{justify-content:center;align-items:center;gap:14px;margin-top:4px;display:flex}.my-challenges-pager-status{color:var(--muted);font-size:.9rem;font-weight:800}.my-challenges-empty{text-align:center;flex:1;place-content:center;justify-items:center;gap:16px;padding:clamp(20px,6vw,52px) 0;display:grid}.my-challenges>.site-footer{margin-top:auto}.my-challenges-empty-emoji{margin:0;font-size:clamp(2.6rem,9vw,4rem);line-height:1}.my-challenges-empty .builder-sub{max-width:38ch;margin:0}.builder-see-puzzles{color:var(--board);font-weight:800}.worksheet-check{gap:var(--space-6);max-width:760px;min-height:100vh;margin:0 auto;padding:clamp(18px,5vw,46px);display:grid}.worksheet-check-hero{gap:var(--space-2);display:grid}.worksheet-check-kicker,.worksheet-check-number,.worksheet-check-secondary{color:var(--muted);font-size:var(--text-sm);margin:0;font-weight:900}.worksheet-check h1{max-width:12ch;color:var(--board);margin:0;font-family:Georgia,Times New Roman,serif;font-size:clamp(2.6rem,8vw,5rem);line-height:.95}.worksheet-check-card{gap:var(--space-5);background:linear-gradient(90deg,#f7c9481c 0 1px,#0000 1px) 0 0/22px 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input{border-radius:var(--radius);width:100%;min-height:58px;color:var(--ink);text-align:center;background:#fffdf5eb;border:1px solid #18211d24;padding:8px 14px;font-size:2rem;font-weight:1000;box-shadow:inset 0 2px #18211d14}.worksheet-check-answer input:focus{border-color:var(--blue);outline:3px solid #4377d92e}.worksheet-check-choices{gap:var(--space-3);display:grid}.worksheet-choice{text-align:left;justify-content:flex-start;width:100%;min-height:56px}.worksheet-choice--selected{border-color:var(--aqua);background:#2bb8a81f}.worksheet-check-secondary a{color:var(--board);font-weight:1000}.worksheet-check-missing{text-align:center;align-content:center}.worksheet-check-missing h1{max-width:none;margin-inline:auto}.worksheet-check-missing p{color:var(--muted);margin:0;font-weight:800}@page{margin:10mm}.worksheet-print{max-width:min(216mm,100vw - 28px);color:var(--ink);margin:0 auto;padding:clamp(16px,4vw,32px) 14px 40px}.worksheet-print-toolbar{align-items:center;gap:var(--space-3) 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7.8mm);flex:1;min-height:28mm}.worksheet-answer-row{align-items:flex-end;gap:6mm;margin-top:auto;padding-top:2mm;display:flex}.worksheet-answer{flex:1;align-items:baseline;gap:10px;font-size:18pt;font-weight:900;display:flex}.worksheet-answer-expr{white-space:nowrap}.worksheet-answer-badge{color:#fff;background:#111;border-radius:50%;align-self:center;place-items:center;width:26px;height:26px;font-size:13pt;font-weight:900;display:grid}.worksheet-answer-blank{border-bottom:2px solid #111;flex:1;min-width:30mm;height:0}.worksheet-choose{gap:3mm;display:grid}.worksheet-choose-prompt{margin:0;font-size:17pt;font-weight:800;line-height:1.2}.worksheet-choose-options{gap:2.5mm;margin:0;padding:0;list-style:none;display:grid}.worksheet-choose-option{align-items:center;gap:10px;font-size:17pt;font-weight:900;display:flex}.worksheet-choose-circle{font-size:20pt;line-height:1}.worksheet-qr{flex-direction:column;align-items:center;gap:1mm;margin-left:auto;display:flex}.worksheet-qr-svg{width:18mm;height:18mm;display:block}.worksheet-qr-caption{font-size:8pt;font-weight:800}.worksheet-page-strip{justify-content:space-between;gap:var(--space-4);color:#555;font-size:9pt;font-weight:800;display:flex}.worksheet-print-missing{gap:var(--space-4);text-align:center;place-content:center;max-width:640px;min-height:100vh;margin:0 auto;padding:clamp(18px,5vw,46px);display:grid}.worksheet-print-missing h1{color:var(--board);margin:0}.worksheet-print-missing p{color:var(--muted);margin:0;font-weight:800}@media print{html,body{background:#fff}.worksheet-print-toolbar{display:none}.worksheet-print{color:#111;max-width:none;margin:0;padding:0}.worksheet-print-page{break-inside:avoid;break-after:page;flex-direction:column;gap:6mm;width:auto;height:248mm;margin:0;padding:3.5mm 3.5mm 0;display:flex}.worksheet-print-page[data-last]{break-after:auto}.worksheet-puzzle{flex:1 1 0;min-height:0}}.coach-overlay{z-index:30;pointer-events:none;position:fixed;inset:0}.coach-spotlight{-webkit-backdrop-filter:brightness(1.18)saturate(1.05);border:3px dashed #f8f2d6f2;border-radius:14px;animation:1.6s ease-in-out infinite coach-spotlight-pulse;position:fixed;box-shadow:0 0 0 5px #f7c94852,0 0 30px 10px #f7c94866,0 0 0 200vmax #18211d4d}@keyframes coach-spotlight-pulse{0%,to{border-color:#f8f2d6f2}50%{border-color:#f7c948f2}}.coach-bubble{background:var(--board);border-radius:var(--radius);width:340px;max-width:calc(100vw - 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