:root{--lightningcss-light: ;--lightningcss-dark:initial;color-scheme:dark;--bg-color:#0b0f19;--surface-main:#131a2a;--surface-highlight:#1e293b;--surface-border:#334155;--surface-glass:#131a2ab3;--text-main:#f8fafc;--text-dim:#94a3b8;--text-primary:#38bdf8;--color-primary:#0ea5e9;--color-primary-glow:#0ea5e966;--color-error:#ef4444;--color-error-bg:#ef44441a;--color-success:#10b981;--color-accent:#8b5cf6;--cell-size:clamp(30px, 10vw, 55px);--cell-border:1px solid #1e293b;--cell-border-thick:2px solid #38bdf8;--cell-bg:var(--surface-main);--cell-bg-selected:#1b2e4b;--cell-bg-related:#16243a;--cell-bg-same-number:#38bdf833;--cell-text-initial:#f8fafc;--cell-text-user:#38bdf8;--cell-text-error:#ef4444;font-synthesis:none;text-rendering:optimizelegibility;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;font-family:Inter,system-ui,Avenir,Helvetica,Arial,sans-serif;font-weight:400;line-height:1.5}*{box-sizing:border-box;margin:0;padding:0}body{background-color:var(--bg-color);min-width:320px;min-height:100vh;color:var(--text-main);background-image:radial-gradient(at top,#1e293b 0%,#0000 80%),radial-gradient(at bottom,#0ea5e922 0%,#0000 60%);place-items:center;margin:0;display:flex}#root{width:100%;max-width:1280px;margin:0 auto;padding:1rem}button{background-color:var(--surface-highlight);color:var(--text-main);cursor:pointer;border:1px solid #0000;border-radius:8px;padding:.6em 1.2em;font-family:inherit;font-size:1em;font-weight:500;transition:all .2s cubic-bezier(.4,0,.2,1)}button:hover{border-color:var(--color-primary);background-color:var(--surface-border);box-shadow:0 0 10px var(--color-primary-glow)}button:focus,button:focus-visible{outline:2px solid var(--color-primary);outline-offset:2px}.glass-panel{background:var(--surface-glass);-webkit-backdrop-filter:blur(10px);border:1px solid var(--surface-border);border-radius:12px}.text-gradient{background:linear-gradient(90deg,#38bdf8,#8b5cf6);-webkit-text-fill-color:transparent;-webkit-background-clip:text;background-clip:text}.sudoku-board{border:var(--cell-border-thick);background:var(--surface-main);grid-template-rows:repeat(9,1fr);width:max-content;margin:0 auto;display:grid;overflow:hidden;box-shadow:0 0 30px #0ea5e926}.sudoku-row{grid-template-columns:repeat(9,1fr);display:grid}.sudoku-row:nth-child(3n){border-bottom:var(--cell-border-thick)}.sudoku-row:last-child{border-bottom:none}.sudoku-cell{width:var(--cell-size);height:var(--cell-size);border-right:var(--cell-border);border-bottom:var(--cell-border);font-size:calc(var(--cell-size) * .5);cursor:pointer;background:var(--cell-bg);-webkit-user-select:none;user-select:none;color:var(--cell-text-user);justify-content:center;align-items:center;transition:background .15s,color .15s;display:flex;position:relative}.sudoku-cell:nth-child(3n){border-right:var(--cell-border-thick)}.sudoku-cell:last-child{border-right:none}.sudoku-cell.initial{color:var(--cell-text-initial);font-weight:600}.sudoku-cell:hover{background:var(--surface-highlight)}.sudoku-cell.related{background:var(--cell-bg-related)}.sudoku-cell.same-number{background:var(--cell-bg-same-number);text-shadow:0 0 10px var(--color-primary)}.sudoku-cell.selected{background:var(--cell-bg-selected);box-shadow:inset 0 0 0 2px var(--color-primary);z-index:10}.sudoku-cell.error{background:var(--color-error-bg);color:var(--color-error);text-shadow:0 0 8px var(--color-error);animation:2s infinite pulse-error}@keyframes pulse-error{0%{box-shadow:inset 0 0 0 2px #0000}50%{box-shadow:inset 0 0 0 2px #ef444480}to{box-shadow:inset 0 0 0 2px #0000}}.notes-grid{grid-template-rows:repeat(3,1fr);grid-template-columns:repeat(3,1fr);width:100%;height:100%;padding:10%;display:grid}.note{font-size:calc(var(--cell-size) * .2);color:#0000;justify-content:center;align-items:center;line-height:1;transition:color .2s;display:flex}.note.visible{color:var(--text-primary)}.controls-container{flex-direction:column;gap:1.5rem;width:100%;display:flex}.controls-container.disabled{opacity:.6;pointer-events:none}.actions-row{justify-content:space-between;gap:.5rem;width:100%;max-width:440px;margin:0 auto;display:flex}.action-btn{color:var(--text-dim);background:0 0;border:none;border-radius:12px;flex-direction:column;flex:1;justify-content:center;align-items:center;gap:.4rem;padding:.75rem .2rem;display:flex;position:relative}.action-btn span{letter-spacing:.5px;font-size:.75rem;font-weight:600}.action-btn .notes-badge{background:var(--surface-border);border-radius:6px;margin-top:-2px;padding:2px 6px;font-size:.6rem}.action-btn.active.notes-active .notes-badge{background:var(--color-primary);color:var(--bg-color)}.action-btn:hover:not(:disabled){color:var(--color-primary);background:var(--surface-main);box-shadow:none}.action-btn:disabled{opacity:.3;cursor:not-allowed}.action-btn.active.notes-active{color:var(--color-primary);background:var(--surface-main);box-shadow:inset 0 0 0 1px var(--color-primary), 0 0 15px var(--color-primary-glow)}.hint-icon-wrapper{display:inline-block;position:relative}.badge{background:var(--color-primary);color:var(--bg-color);border-radius:9px;justify-content:center;align-items:center;min-width:18px;height:18px;padding:0 4px;font-size:.7rem;font-weight:700;display:flex;position:absolute;top:-8px;right:-12px}.numpad{grid-template-rows:repeat(3,1fr);grid-template-columns:repeat(3,1fr);gap:1rem;width:100%;max-width:440px;margin:0 auto;display:grid}.numpad-btn{color:var(--color-primary);aspect-ratio:1;background:var(--surface-main);border:1px solid var(--surface-border);border-radius:12px;justify-content:center;align-items:center;width:100%;height:auto;padding:0;font-size:2.2rem;font-weight:500;transition:all .2s;display:flex}.numpad-btn:active:not(:disabled){background:var(--surface-highlight);transform:scale(.95)}.numpad-btn.completed{visibility:hidden;opacity:0;pointer-events:none}@media (width<=1023px){.actions-row{max-width:100%;margin-bottom:.5rem}.numpad{grid-template-rows:auto;grid-template-columns:repeat(9,1fr);gap:.2rem;width:100%;max-width:100%}.numpad-btn{border-radius:8px;height:auto;font-size:1.5rem}}.app-container{flex-direction:column;min-height:100vh;padding:1rem;display:flex}.header{flex-direction:column;align-items:center;gap:1.5rem;width:100%;padding:0 0 2rem;display:flex}.difficulty-selector{background:var(--surface-main);border:1px solid var(--surface-border);border-radius:999px;flex-wrap:wrap;justify-content:center;gap:.5rem;padding:.5rem;display:flex}.diff-btn{color:var(--text-dim);background:0 0;border:none;border-radius:999px;padding:.6rem 1.25rem;font-size:.95rem;font-weight:600}.diff-btn:hover{color:var(--text-main);background:#ffffff0d}.diff-btn.active{background:var(--surface-highlight);color:var(--color-primary);box-shadow:0 0 12px var(--color-primary-glow)}.header-top{align-items:center;gap:2rem;display:flex}.logo{letter-spacing:2px;text-transform:lowercase;margin:0;font-size:2.5rem;font-weight:800}.seed-btn{color:var(--text-dim);background:var(--surface-main);border:1px solid var(--surface-border);border-radius:12px;padding:.4rem 1rem;font-family:monospace;font-size:.8rem;transition:border-color .2s,color .2s}.seed-btn:hover{border-color:var(--color-primary);color:var(--text-main)}.main-content{flex-direction:column;align-items:center;gap:1.5rem;display:flex}.board-wrapper{flex-direction:column;gap:.5rem;display:flex}.board-header{color:var(--text-dim);justify-content:space-between;align-items:center;padding:0 .5rem;font-size:.9rem;display:flex}.difficulty-label strong{color:var(--color-primary)}.timer{cursor:pointer;border-radius:6px;align-items:center;gap:.5rem;padding:.2rem .5rem;transition:background .2s;display:flex}.timer:hover{background:var(--surface-main);color:var(--text-main)}.board-container{position:relative}.board-blurred{filter:blur(8px);pointer-events:none;opacity:.3}.overlay{z-index:20;text-align:center;flex-direction:column;align-items:center;gap:1rem;min-width:250px;padding:2rem 3rem;display:flex;position:absolute;top:50%;left:50%;transform:translate(-50%,-50%)}.overlay h2{color:var(--text-main);margin:0;font-size:2rem}.overlay.error h2{color:var(--color-error)}.overlay.success h2{color:var(--color-success)}.resume-btn,.new-game-btn-large{background:var(--color-primary);color:#fff;cursor:pointer;border:none;border-radius:20px;padding:.8rem 2rem;font-size:1.2rem;font-weight:600;transition:filter .2s}.resume-btn:hover,.new-game-btn-large:hover{filter:brightness(1.2)}.controls-section{flex-direction:column;align-items:center;gap:1.5rem;width:100%;display:flex}.new-game-btn{background:var(--surface-main);border:1px solid var(--color-primary);color:var(--color-primary);cursor:pointer;border-radius:99px;width:100%;max-width:440px;padding:.8rem 2rem;font-size:1.2rem;font-weight:600;transition:all .2s}.new-game-btn:hover{background:var(--color-primary);color:#fff}.dialog-overlay{-webkit-backdrop-filter:blur(4px);backdrop-filter:blur(4px);z-index:100;background:#0009;justify-content:center;align-items:center;display:flex;position:fixed;inset:0}.dialog-content{flex-direction:column;gap:1rem;width:90%;max-width:400px;padding:2rem;display:flex}.dialog-content h3{color:var(--text-main);margin:0}.dialog-desc{color:var(--text-dim);margin:0;font-size:.9rem}.dialog-content input{border:1px solid var(--surface-border);background:var(--surface-main);color:var(--text-primary);border-radius:8px;padding:.8rem;font-family:monospace;font-size:1.1rem}.dialog-content input:focus{outline:2px solid var(--color-primary);border-color:#0000}.dialog-actions{justify-content:flex-end;gap:1rem;margin-top:1rem;display:flex}.dialog-actions .secondary{border:1px solid var(--surface-border);background:0 0}.dialog-actions .primary{background:var(--color-primary);color:#fff}@media (width>=1024px){.header{padding-left:0}.main-content{flex-direction:row;justify-content:center;align-items:flex-start;gap:5rem;padding-top:1rem}.controls-section{max-width:440px}}