:root{--primary-color: #40513B;--bg-color: #F8EDE3;--popup-overlay-color: rgba(0, 0, 0, .85);--popup-bg-color: #F8EDE3;--popup-important-bg-color: #D0B8A8 --popup-shadow-color: rgba(0, 0, 0, .6);--primary-shadow-color: rgba(255, 0, 102, .1);--side-bar-color: #080808;--text-color: #181818;--text-error-color: #181818;--text-selected-color: #181818;--text-light-error-color: E84545;--text-light-selected-color: #181818;--text-hover-color: #181818;--text-error-hover-color: #181818;--text-selected-hover-color: #181818;--text-light-error-hover-color: #181818;--text-light-selected-hover-color: #181818;--cell-color: transparent;--cell-error-color: #E84545;--cell-selected-color: #BDD2B6;--cell-light-error-color: #88304E;--cell-light-selected-color: #798777;--cell-hover-color: #AEBDCA;--cell-error-hover-color: #903749;--cell-selected-hover-color: #7895B2;--cell-light-error-hover-color: #AEBDCA;--cell-light-selected-hover-color: #AEBDCA;--line-color: #609966;--region-line-color: var(--primary-color)}.grid{position:relative;width:1024px;height:1024px;transition:all .3s ease}.cell{display:flex;flex-direction:column;justify-content:center;align-items:center}.cell p{color:var(--text-color);transition:all .3s ease;font-size:2rem}.cell .overlay{transition:all .3s ease}section{flex-grow:1;height:100%;display:flex;justify-content:center;align-items:center;transition:.3s}.left{justify-content:right}.right{justify-content:left}.guide-overlay{position:fixed;top:0;left:0;right:0;bottom:0;background:var(--popup-overlay-color);z-index:999;display:none}.guide-overlay.visible{display:block}.close-guide{position:absolute;top:15px;right:15px;background:none;border:0;color:var(--text-color);font-size:24px;line-height:1;cursor:pointer;padding:5px;transition:color .2s ease}.close-guide:hover{color:var(--primary-color)}.sudoku-guide{display:none;position:fixed;left:50%;top:50%;transform:translate(-50%,-50%);z-index:1000;width:800px;background:var(--popup-bg-color);border:1px solid var(--line-color);border-radius:8px;box-shadow:0 8px 30px var(--popup-shadow-color);padding:30px;opacity:0;transition:opacity .2s ease,transform .2s ease}.sudoku-guide.visible{display:block;opacity:1;transform:translate(-50%,-50%) scale(1)}.sudoku-guide h3{margin:0 0 15px;font-size:1.5em;border-bottom:1px solid var(--line-color);padding-bottom:8px;position:relative}.sudoku-guide ul{padding-left:20px;margin:15px 0}.sudoku-guide li{margin-bottom:8px}.sudoku-guide strong{color:var(--primary-color);font-weight:700}.controls-list{background:var(--popup-important-bg-color);padding:15px;border-radius:6px;margin:20px 0;border:1px solid var(--line-color);position:relative}.controls-list:before{content:"";position:absolute;top:-1px;left:-1px;right:-1px;bottom:-1px;border:1px solid var(--primary-color);border-radius:6px;opacity:.2}.controls-list p{margin:0 0 10px;font-weight:700}.timer-note{font-style:italic}.mistakes-label{font-size:2rem;max-width:70px;min-width:70px}.controls-panel{flex:0 0 220px;border-left:1px solid;border-image:linear-gradient(to bottom,transparent 0%,var(--line-color) 15%,var(--line-color) 85%,transparent 100%) 1;padding:0 0 0 25px}.timer-display{font-size:1.3em;margin:0 0 30px;font-family:monospace;letter-spacing:1px;position:relative}.timer-display:after{content:"";position:absolute;bottom:-15px;left:0;width:30%;height:1px;background:var(--primary-color);opacity:.3}.controls-buttons{display:flex;flex-direction:column;gap:8px}.ctrl-btn{background:none;border:0;color:var(--text-color);padding:8px 0;text-align:left;cursor:pointer;transition:all .2s ease;border-radius:3px;display:flex;align-items:center;gap:8px;width:fit-content}.ctrl-btn:hover{color:var(--primary-color);text-shadow:0 0 8px var(--primary-shadow-color)}.ctrl-btn svg{width:16px;height:16px;fill:currentColor;opacity:.8}.how-to-play-btn{position:absolute;right:15px;bottom:15px;background:var(--line-color);border:2px solid var(--line-color);color:var(--text-color);width:40px;height:40px;border-radius:50%;cursor:pointer;transition:all .2s ease;display:flex;align-items:center;justify-content:center;font-size:1.2em;margin-top:20px}.how-to-play-btn:hover{border-color:var(--region-line-color);transform:scale(1.1)}.how-to-play-btn:after{content:"How to Play";position:absolute;top:-50px;right:0;background:var(--popup-bg-color);color:var(--text-color);padding:6px 12px;border-radius:4px;font-size:.9em;white-space:nowrap;border:1px solid var(--line-color);opacity:0;transition:opacity .2s ease;pointer-events:none;box-shadow:0 2px 8px #0003}.how-to-play-btn:hover:after{opacity:1}.how-to-play-btn span{position:relative;top:-1px}.pause-overlay{position:absolute;top:0;left:0;width:100%;height:100%;font-size:5rem;display:flex;justify-content:center;align-items:center;background-color:var(--bg-color);transition:all .3s ease;opacity:0;z-index:99;pointer-events:none}@media only screen and (max-width: 768px){.grid{width:500px;height:500px}.cell p{font-size:1rem}}*{margin:0;padding:0;box-sizing:border-box}body{width:100vw;height:100vh;font-family:Poppins,sans-serif;font-weight:400;font-style:normal;font-size:1.3rem;background-color:var(--bg-color);color:var(--text-color);padding:2rem;display:flex;justify-content:center;align-items:center;gap:5rem}