:root{color:#172019;font-synthesis:none;text-rendering:optimizelegibility;--felt:#17633f;--felt-dark:#0f4a2e;--ink:#172019;--line:#829287;--strong-line:#243d2e;--focus:#ffca55;background:#17633f;font-family:system-ui,-apple-system,BlinkMacSystemFont,Segoe UI,sans-serif}*{box-sizing:border-box}body{background:var(--felt);min-width:0;min-height:100vh;margin:0}button,select{font:inherit;min-height:42px;color:var(--ink);background:#fff;border:1px solid #a9b7ad;border-radius:4px}button{cursor:pointer;padding:.55rem .75rem;font-weight:700}button:hover:not(:disabled){background:#f2f8f3;border-color:#3f6c51}button:focus-visible,select:focus-visible{z-index:5;outline:3px solid var(--focus);outline-offset:1px;position:relative}button:disabled{cursor:not-allowed;opacity:.5}.primary-button{color:#fff;background:#12633b;border-color:#0b4a2c}.primary-button:hover:not(:disabled){background:#0c4d2d}.game-screen{background:radial-gradient(circle at top left, #ffffff14, transparent 34rem), linear-gradient(135deg, var(--felt), var(--felt-dark));min-height:100vh}.game-header{color:#132018;background:#fff;min-height:72px;padding:.7rem clamp(.75rem,2.5vw,1.5rem)}.game-header h1{margin:0;font-family:Georgia,Yu Mincho,serif;font-size:2rem}.game-heading{flex-direction:column;align-items:flex-start;gap:.2rem;margin-left:-4px;display:flex}.breadcrumb{color:#000;align-items:center;gap:.4rem;margin-left:4px;font-size:clamp(.72rem,2.2vw,.86rem);line-height:1.4;display:flex}.breadcrumb a,.breadcrumb span{color:#000}.game-layout{grid-template-columns:minmax(280px,600px) minmax(240px,310px);justify-content:start;align-items:start;gap:clamp(.7rem,2vw,1.3rem);width:min(100%,1050px);padding:clamp(.65rem,2vw,1.4rem);display:grid}.board-panel,.control-panel{border:1px solid #ffffff57;border-radius:4px}.board-panel{background:#04291738;min-width:0;padding:clamp(.45rem,1.4vw,.85rem)}.board-heading{color:#fff;text-align:left;min-height:30px}.sudoku-board{aspect-ratio:1;background:#fff;grid-template-columns:repeat(9,minmax(0,1fr));width:100%;display:grid}.sudoku-cell{aspect-ratio:1;border:0;border-top:1px solid var(--line);border-left:1px solid var(--line);color:#154f84;background:#fff;border-radius:0;place-items:center;min-width:0;min-height:0;padding:0;font-size:clamp(1rem,4.4vw,2rem);line-height:1;display:grid;position:relative}.sudoku-cell:hover:not(:disabled){border-color:var(--line);background:#eef6ef}.sudoku-cell.block-left{border-left:3px solid var(--strong-line)}.sudoku-cell.block-top{border-top:3px solid var(--strong-line)}.sudoku-cell.board-right{border-right:3px solid var(--strong-line)}.sudoku-cell.board-bottom{border-bottom:3px solid var(--strong-line)}.sudoku-cell.is-related{background:#eef3ed}.sudoku-cell.is-same{background:#d6ead9}.sudoku-cell.is-selected{z-index:2;background:#c2dfc8;box-shadow:inset 0 0 0 3px #17633f}.sudoku-cell.is-initial{color:#172019;font-weight:850}.sudoku-cell.is-player{color:#145ca0}.sudoku-cell.is-conflict{color:#a51f17;background:#ffe3df}.sudoku-cell.is-hint-unit{background:#fff1bd}.sudoku-cell.is-hint-cell{z-index:3;background:#ffd35f;box-shadow:inset 0 0 0 3px #8f6500}.sudoku-cell:disabled{opacity:1}.cell-value{font-weight:720}.control-panel{color:var(--ink);background:#fff;gap:.65rem;padding:.8rem;display:grid}.control-panel h2{border-bottom:1px solid #d4ddd6;margin:0;padding-bottom:.35rem;font-size:1rem}.setting-field{justify-content:space-between;align-items:center;gap:.7rem;min-height:44px;display:flex}.setting-field span{font-weight:750}.setting-field select{min-width:9.5rem;padding:.35rem}.game-actions,.edit-actions,.dialog-actions{gap:.5rem;display:grid}.game-actions button,#start-new{width:100%}.number-section{gap:.55rem;display:grid}.number-pad{grid-template-columns:repeat(3,1fr);gap:.35rem;display:grid}.number-button{place-items:center;min-width:0;min-height:54px;padding:.25rem;display:grid}.number-button strong{font-size:1.3rem}.number-button small{font-size:.65rem;font-weight:600}.edit-actions{grid-template-columns:repeat(2,minmax(0,1fr))}.dialog-backdrop{z-index:1000;background:#031009b8;place-items:center;padding:1rem;display:grid;position:fixed;inset:0;overflow-y:auto}.dialog-card{background:#fff;border:1px solid #d6dfd8;border-radius:4px;width:min(560px,100%);max-height:calc(100vh - 2rem);padding:clamp(1rem,4vw,1.8rem);overflow-y:auto;box-shadow:0 24px 80px #00000059}.dialog-card h2{margin-top:0}.dialog-card h3{margin-bottom:.2rem}.dialog-card p{line-height:1.65}.rules-dialog ul{line-height:1.8}.dialog-actions{grid-template-columns:repeat(auto-fit,minmax(10rem,1fr));margin-top:1rem}.rules-dialog>button{width:100%;margin-top:.6rem}@media (width<=760px){.game-layout{grid-template-columns:minmax(0,600px);justify-content:center}.control-panel{grid-template-columns:repeat(2,minmax(0,1fr))}.control-panel>h2,.setting-field,.number-section,#start-new,.edit-actions,.game-actions{grid-column:1/-1}.number-pad{grid-template-columns:repeat(9,minmax(0,1fr))}.number-button{min-height:48px}.number-button small{display:none}}@media (width<=420px){.game-header{min-height:62px;padding:.55rem .65rem}.game-layout{gap:.55rem;padding:.5rem}.board-panel,.control-panel{padding:.45rem}.board-heading{min-height:26px;font-size:.84rem}.sudoku-cell{font-size:clamp(1rem,7vw,1.45rem)}.control-panel{gap:.45rem}.number-pad{gap:.2rem}.number-button{min-height:42px;padding:.1rem}.number-button strong{font-size:1rem}}