:root{color-scheme:light;--paper:#faf4e8;--ink:#443329;--muted:#786858;--brick:#e9ad87;--accent:#8a452e;--line:#d8c8b3;--focus:#145b67;font-family:ui-rounded,'Avenir Next',Avenir,'Trebuchet MS',sans-serif;background:var(--paper);color:var(--ink)}
*{box-sizing:border-box}body{margin:0;background:radial-gradient(ellipse at 12% 10%,#f0dab94d,transparent 52%)}button,input,select{font:inherit}button,a,input,select{-webkit-tap-highlight-color:transparent}button,select,input{min-height:44px}button{border:1px solid var(--line);border-radius:8px;background:#fffaf1;color:var(--ink);padding:9px 15px;cursor:pointer;transition:background .15s,transform .15s,box-shadow .15s}button:hover:not(:disabled){background:#f5e1c8}button:active:not(:disabled){transform:translateY(1px)}button:disabled{opacity:.45;cursor:default}a{color:var(--accent);text-underline-offset:4px}a:hover{text-decoration-thickness:2px}a:focus-visible,button:focus-visible,input:focus-visible,select:focus-visible{outline:3px solid var(--focus);outline-offset:4px}[hidden]{display:none!important}.skip{position:absolute;left:16px;top:-90px;background:#fff;padding:12px;z-index:5}.skip:focus{top:8px}header,main,footer{width:min(1020px,calc(100% - 40px));margin:auto}header{display:flex;align-items:center;justify-content:space-between;gap:12px;padding:24px 0}header>a:last-child{padding:12px 0}.brand{display:flex;gap:10px;align-items:center;font-weight:750;font-size:23px;letter-spacing:-.7px;text-decoration:none;color:var(--ink)}.brand svg{color:#ac6748}.heading{padding:20px 0 25px}h1{font-weight:650;font-size:clamp(29px,4.2vw,47px);line-height:1.1;letter-spacing:-1.6px;margin:0 0 12px}.heading p{font-size:17px;margin:0;color:var(--muted)}.workbench{border-top:2px solid var(--ink);border-bottom:1px solid var(--line);padding:20px 0 26px}.toolbar{display:flex;align-items:center;justify-content:space-between;gap:14px;flex-wrap:wrap}.mode-switch{display:flex;background:#efe4d2;border-radius:9px;padding:3px;gap:2px}.mode-switch button{border:0;background:transparent;min-width:83px}.mode-switch button[aria-pressed=true]{background:#fffaf1;box-shadow:0 1px 4px #56381c20;font-weight:700}.toolbar label{display:flex;align-items:center;gap:9px;font-size:14px}.toolbar select{padding:5px 28px 5px 12px;color:var(--ink);border:1px solid var(--line);border-radius:8px;background:#fffaf1}.workspace{display:grid;grid-template-columns:minmax(0,1.5fr) minmax(240px,1fr);gap:55px;padding-top:27px}.board-meta{display:flex;justify-content:space-between;gap:8px;font-size:13px;color:var(--muted);font-variant-numeric:tabular-nums}.pyramid{--brick-width:clamp(52px,calc((100vw - 76px)/4),84px);display:flex;flex-direction:column;gap:11px;justify-content:center;min-height:310px;padding:26px 0 22px}.brick-row{display:flex;justify-content:center;gap:9px}.brick{position:relative;min-width:0;width:var(--brick-width);height:61px;min-height:52px;padding:5px;border-radius:5px 7px 6px 4px;border:1px solid #b77c54;background:#f4c6a4;box-shadow:0 4px 0 #c790682f,inset 0 1px #fff5;font-size:25px;font-weight:650;font-variant-numeric:tabular-nums}.brick.given{background:#e6d6be;border-color:#c2ac8c;color:#685641}.brick .lock-dot{position:absolute;right:6px;bottom:4px;font-size:7px}.brick .wrong-mark{position:absolute;left:5px;top:1px;font-size:11px;font-weight:800;display:none}.brick.conflict .wrong-mark{display:block}.brick.related{box-shadow:0 4px 0 #c790682f,inset 0 0 0 2px #b06b4630}.brick.selected{border:2px solid #8a452e;background:#f1ad7e;box-shadow:0 4px #9f634930}.brick.hinted{animation:hint-warm .8s ease-out}.brick[aria-disabled=true]{cursor:default}.brick.conflict{border:2px dashed #a23426}.brick:disabled{opacity:1}.brick:hover:not(:disabled){background:#ffd5b3}.given-legend{font-size:12px;color:var(--muted);text-align:center;margin:0}.given-legend span{font-size:7px;vertical-align:2px;margin-right:5px}.entry-side{align-self:center}.selection{font-size:14px;margin:0 0 16px;font-weight:650}#entry-form label{font-size:14px;display:flex;justify-content:space-between;margin-bottom:6px}.range{color:var(--muted);font-size:12px}.entry-line{display:grid;grid-template-columns:minmax(0,1fr) auto;gap:8px}input{min-width:0;width:100%;border:1px solid #b5a18a;border-radius:7px;padding:7px 12px;background:#fffdf8;color:var(--ink);font-size:23px;font-variant-numeric:tabular-nums}.entry-line button,.finish button{background:var(--accent);border-color:var(--accent);color:#fffdf6;font-weight:650}.entry-line button:hover:not(:disabled),.finish button:hover{background:#733b29}.digit-pad{display:grid;grid-template-columns:repeat(5,minmax(0,1fr));gap:6px;margin:10px 0 6px}.digit-pad button{padding:7px 0;font-size:17px}.erase{width:100%;background:transparent;border:0;font-size:13px;min-height:44px}.equation-note{border-left:3px solid #bf8261;padding:2px 0 2px 13px;margin-top:10px;color:var(--muted)}.equation-note span{font-size:12px}.equation-note p{font-size:20px;margin:3px 0;color:var(--ink);font-variant-numeric:tabular-nums;letter-spacing:.3px}.feedback{font-size:14px;line-height:1.5;min-height:43px;margin:16px 0 10px}.actions{display:flex;gap:7px;flex-wrap:wrap}.actions button{padding:8px 11px;font-size:13px}.actions #new-puzzle{margin-left:auto}.finish{padding:20px 0 26px;color:#486045}.finish h2{font-size:28px;letter-spacing:-.8px;margin:12px 0 24px}.finish button{min-width:170px}.error{font-size:13px;color:#a23426;margin:8px 0}.small-guide{display:grid;grid-template-columns:1fr 1.7fr;gap:8px 25px;padding:32px 0 21px;align-items:start}.small-guide h2{font-size:21px;letter-spacing:-.3px;margin:0;grid-row:span 2}.small-guide p{margin:0;font-size:14px;line-height:1.7;color:var(--muted)}.small-guide a{font-size:13px;justify-self:start;padding:8px 0}.library-note{color:var(--muted);font-size:12px;line-height:1.6;margin:15px 0 36px}.notice{border-left:3px solid #a95935;background:#f5e4ce;padding:14px 16px;margin-top:20px}.notice p{font-size:14px;line-height:1.5;margin:0 0 10px}.notice details{margin-top:12px;font-size:13px}.notice pre{white-space:pre-wrap;overflow-wrap:anywhere;max-width:100%;font-size:12px}.notice summary{cursor:pointer;padding:10px 0;min-height:44px}footer{display:flex;justify-content:space-between;gap:16px;padding:23px 0;border-top:1px solid var(--line);font-size:13px;color:var(--muted)}footer nav{display:flex;gap:16px}footer a{display:inline-block;padding:8px 0}dialog{width:min(440px,calc(100% - 32px));border:1px solid var(--line);border-radius:12px;background:var(--paper);color:var(--ink);padding:24px;box-shadow:0 18px 90px #33221844}dialog::backdrop{background:#3d2c2170}dialog h2{font-size:24px;letter-spacing:-.5px;margin:0 0 12px}dialog p{font-size:15px;line-height:1.6}.dialog-actions{display:flex;justify-content:flex-end;gap:10px;margin-top:24px}.dialog-actions button:last-child{background:var(--accent);color:white}.rules{max-width:730px;line-height:1.8}.rules h1{margin:25px 0}.rules h2{font-size:23px;margin-top:32px}.rules li{margin:10px 0}.worked-pyramid{max-width:350px;margin:25px auto;display:flex;flex-direction:column;gap:10px}.worked-pyramid div{display:flex;justify-content:center;gap:9px}.worked-pyramid span{background:#edc1a0;border:1px solid #bd906c;border-radius:5px;padding:10px;width:65px;text-align:center;font-size:22px;font-weight:650}.play-link{display:inline-block;padding:9px 18px;background:var(--accent);color:white;text-decoration:none;border-radius:8px;min-height:44px;margin:15px 0 30px}
@keyframes hint-warm{from{box-shadow:0 0 0 7px #c98b4660}to{box-shadow:0 4px 0 #c790682f}}
@media(max-width:700px){header,main,footer{width:calc(100% - 32px)}header{padding:16px 0}.heading{padding:13px 0 20px}.heading p{font-size:15px}.workspace{grid-template-columns:1fr;gap:24px;padding-top:20px}.entry-side{width:min(100%,370px);margin:auto}.pyramid{min-height:0;padding:24px 0 19px}.brick{height:56px}.toolbar{gap:10px}.toolbar label{gap:6px}.mode-switch button{min-width:70px;padding:9px 10px}.small-guide{display:block;padding-top:25px}.small-guide h2{margin-bottom:10px}.small-guide a{display:inline-block}.finish{text-align:center;padding:4px 0 15px}.finish h2{margin:3px 0 15px}.library-note{margin-bottom:25px}footer{align-items:center}footer nav{gap:12px}}
@media(prefers-reduced-motion:reduce){*,*::before,*::after{animation:none!important;transition:none!important}}