:root{color-scheme:dark;--bg:#11121a;--paper:#1c1d29;--ink:#f5f3ec;--muted:#a1a3b5;--line:#3a3b4d;--heavy:#a4a0bc;--accent:#c2adff;--related:#252637;--same:#363047;--selected:#4d4269;--coral:#ff9a86;--green:#c6eea1}body.light{color-scheme:light;--bg:#f6f4ee;--paper:#fffef9;--ink:#292b3d;--muted:#747587;--line:#dfdce7;--heavy:#69637c;--accent:#7353a5;--related:#f1edf8;--same:#e7ddf5;--selected:#d8c5ed;--coral:#b84239;--green:#3f7144}*{box-sizing:border-box}body{margin:0;background:var(--bg);color:var(--ink);font:14px/1.6 Arial,sans-serif}.app{max-width:490px;margin:auto;padding:20px 19px 25px}button,select{font:inherit;color:inherit}button{cursor:pointer;border:0;background:var(--paper);border-radius:10px;padding:9px 12px;min-height:40px;touch-action:manipulation}button:focus-visible,select:focus-visible,a:focus-visible,input:focus-visible{outline:3px solid #ffb77a;outline-offset:3px}button:disabled{opacity:.4;cursor:default}header{display:flex;align-items:center;justify-content:space-between;margin-bottom:23px}header>div{display:flex;gap:7px}header button{width:39px}.brand{font-size:23px;letter-spacing:-1px;font-weight:900;text-decoration:none;color:var(--ink)}.brand span,h1 span{color:#ff995e}.title{display:flex;align-items:center;justify-content:space-between}.eyebrow{font-size:8px;font-weight:bold;letter-spacing:1.5px;color:var(--muted)}h1{font-size:48px;line-height:1.1;letter-spacing:-2.5px;margin:8px 0 17px}.dailybadge{font-size:8px;letter-spacing:1px;text-align:right;color:var(--accent)}.dailybadge b{font-size:11px;letter-spacing:0}.meta{display:flex;justify-content:space-between;align-items:center;margin-bottom:12px}.meta select{background:none;border:0;font-size:13px;font-weight:bold;padding:8px 0}.meta select option{background:var(--paper)}#progress{font-size:10px;color:var(--muted);font-variant-numeric:tabular-nums}.timer{display:flex;align-items:center;gap:10px;font-size:12px;color:var(--muted);font-variant-numeric:tabular-nums}.timer button{min-height:32px;width:32px;padding:3px}.board-wrap{position:relative}.board{display:grid;grid-template-columns:repeat(9,minmax(0,1fr));aspect-ratio:1;background:var(--paper);border:2px solid var(--heavy);border-radius:9px;overflow:hidden;isolation:isolate}.cell{border-radius:0;min-height:0;min-width:0;padding:0;border-right:1px solid var(--line);border-bottom:1px solid var(--line);font-size:clamp(20px,6vw,29px);font-weight:500;line-height:1;color:var(--accent);position:relative;display:flex;align-items:center;justify-content:center;transition:background-color .15s}.cell:nth-child(3n){border-right:2px solid var(--heavy)}.cell:nth-child(9n){border-right:0}.cell:nth-child(n+19):nth-child(-n+27),.cell:nth-child(n+46):nth-child(-n+54){border-bottom:2px solid var(--heavy)}.cell:nth-child(n+73){border-bottom:0}.cell.given{color:var(--ink);font-weight:700}.cell.related{background:var(--related)}.cell.same{background:var(--same)}.cell.selected{background:var(--selected);box-shadow:inset 0 0 0 2px var(--accent)}.cell.error{color:var(--coral)}.cell.error::after{content:'';position:absolute;bottom:4px;width:4px;height:4px;background:var(--coral);border-radius:50%}.cell.hint{box-shadow:inset 0 0 0 2px var(--green)}.notes-grid{display:grid;grid-template-columns:repeat(3,1fr);align-items:center;width:100%;height:100%;padding:3px;font:10px Arial;color:var(--muted)}.notes-grid span{text-align:center}.unit-pop{animation:unitGlow .85s ease both;animation-delay:var(--delay,0ms)}.digit-pop{animation:digitPop .23s ease}.shake{animation:shake .3s ease}.progress-track{height:3px;border-radius:4px;background:var(--line);margin-top:12px;overflow:hidden}.progress-track span{height:100%;display:block;background:var(--accent);transition:width .5s}.feedback{display:flex;align-items:center;gap:8px;min-height:58px}.feedback p{font-size:11px;color:var(--muted);margin:10px 0;line-height:1.7;flex:1}.feedback>span{color:var(--green);font-size:25px}.feedback.celebrating p{color:var(--green)}.tools{display:grid;grid-template-columns:repeat(5,1fr);gap:4px;margin:0 0 17px}.tools button{background:transparent;font-size:10px;padding:7px 1px;min-height:60px;color:var(--muted)}.tools b{display:block;font-weight:400;font-size:23px;color:var(--ink);line-height:1.4}.tools .active{background:var(--same);color:var(--accent)}.numbers{display:grid;grid-template-columns:repeat(9,minmax(0,1fr));gap:5px}.numbers button{padding:9px 0 7px;font-size:25px;min-height:62px;color:var(--accent);line-height:1}.numbers small{display:block;font-size:8px;color:var(--muted);margin-top:9px}.check{display:flex;align-items:center;gap:6px;font-size:10px;color:var(--ink);margin:20px 0}.check input{accent-color:var(--accent);width:14px;height:14px}.check span{margin-left:auto;font-size:9px;color:var(--muted)}.actions{display:flex;gap:10px}.actions button{flex:1;min-height:45px;font-size:12px}.primary{background:var(--accent);color:var(--bg);font-weight:bold}.footnote{font-size:9px;text-align:center;color:var(--muted);line-height:1.8;margin-top:18px}footer{text-align:center;font-size:8px;letter-spacing:1px;color:var(--muted);margin-top:23px}.pause-cover{position:absolute;inset:0;display:flex;flex-direction:column;justify-content:center;align-items:center;background:var(--paper);border-radius:9px;border:2px solid var(--heavy);z-index:4}.pause-cover>span{font-size:40px;color:var(--accent)}.pause-cover h2{font-size:25px;margin:12px 0 0}.pause-cover p{font-size:12px;color:var(--muted);margin:10px 0 23px}dialog{background:var(--paper);color:var(--ink);border:1px solid var(--line);border-radius:20px;padding:34px 26px;max-width:390px;width:calc(100% - 30px)}dialog::backdrop{background:#080811bb;backdrop-filter:blur(5px)}dialog h2{font-size:29px;letter-spacing:-1px;margin:15px 0}dialog p{font-size:13px;line-height:1.9;color:var(--muted);white-space:pre-line}#modalActions{display:flex;gap:9px;margin-top:23px;flex-wrap:wrap}#modalActions button{font-size:12px}.close{position:absolute;right:8px;top:6px;font-size:24px;background:none}.confetto{position:fixed;top:-20px;width:8px;height:14px;z-index:20;pointer-events:none;animation:fall 2.5s ease-in forwards}#confetti{pointer-events:none}[hidden]{display:none!important}@keyframes unitGlow{0%{background:var(--selected);box-shadow:inset 0 0 0 0 var(--green)}35%{background:var(--green);color:var(--bg);box-shadow:inset 0 0 0 2px var(--green)}100%{box-shadow:inset 0 0 0 0 transparent}}@keyframes digitPop{0%{transform:scale(.7)}65%{transform:scale(1.15)}100%{transform:scale(1)}}@keyframes shake{25%,75%{transform:translateX(-3px)}50%{transform:translateX(3px)}}@keyframes fall{to{transform:translate(var(--drift),105vh) rotate(600deg);opacity:0}}@media(max-width:360px){.app{padding:16px 11px}.numbers{gap:3px}.numbers button{min-height:56px;font-size:23px}.notes-grid{font-size:8px;padding:2px}.check span{font-size:8px}h1{font-size:43px}}@media(prefers-reduced-motion:reduce){*,*::before,*::after{animation:none!important;transition:none!important}}

/* V4: number pad stays directly below the board; feedback expands only as needed. */
.app{padding-top:15px}header{margin-bottom:15px}h1{font-size:43px;margin-bottom:13px}.meta{margin-bottom:9px}.numbers{margin-top:10px;gap:5px}.numbers button{min-height:57px;padding:8px 0 6px;user-select:none;-webkit-user-select:none;-webkit-touch-callout:none;touch-action:none}.numbers small{margin-top:7px}.numbers .digit-highlight{background:var(--selected);box-shadow:inset 0 0 0 1px var(--accent)}.tools{margin:9px 0 4px}.tools button{min-height:49px;padding:3px 1px}.tools b{font-size:21px}.progress-track{margin-top:5px}.feedback{min-height:34px;align-items:flex-start}.feedback p{margin:8px 0;font-size:10px;line-height:1.65}.feedback>span{font-size:21px;margin-top:3px}.check{margin:10px 0}.restart{display:block;background:transparent;color:var(--muted);font-size:10px;margin:8px auto 0;min-height:35px;padding:5px 14px}.footnote{margin:3px 0 0;font-size:8px}footer{margin-top:15px}.cell.hint-context{background:var(--related);box-shadow:inset 0 0 0 1px color-mix(in srgb,var(--green) 25%,transparent)}.cell.hint{background:var(--same);box-shadow:inset 0 0 0 2px var(--green)}
@media(max-height:780px) and (max-width:600px){header{margin-bottom:10px}.app{padding-top:10px;padding-bottom:12px}.eyebrow{font-size:7px}h1{font-size:36px;margin:5px 0 8px}.meta{margin-bottom:7px}.numbers{margin-top:8px}.numbers button{min-height:51px;font-size:23px}.numbers small{margin-top:5px}.tools{margin-top:5px}.tools button{min-height:44px}.tools b{font-size:19px}footer{margin-top:10px}}
@media(max-width:360px){.numbers{gap:3px}.numbers button{min-height:50px;font-size:22px}.check{margin-top:8px}}