:root {
    --bg-main: #F3EFE4;
    --bg-panel: rgba(255, 255, 255, 0.5);
    --bg-element: rgba(0, 0, 0, 0.05);
    --bg-cell: rgba(0, 0, 0, 0.02);
    --bg-cell-selected: rgba(0, 0, 0, 0.1);
    --text-primary: #2c2c2e;
    --text-secondary: #5E5E60;
    --border-color: rgba(0, 0, 0, 0.1);
    --border-heavy: #2c2c2e;
    --accent-primary: #8E8E93;
    --accent-secondary: #AEAEB2;
    --shadow-color: rgba(0, 0, 0, 0.1);
    --conflict-color: #FF3B30;
    --note-color: #5E5E60; 
}
[data-theme="dark"] {
    --bg-main: #1c1c1e;
    --bg-panel: rgba(0, 0, 0, 0.2);
    --bg-element: rgba(255, 255, 255, 0.1);
    --bg-cell: rgba(255, 255, 255, 0.05);
    --bg-cell-selected: rgba(255, 255, 255, 0.2);
    --text-primary: #F3EFE4;
    --text-secondary: #AEAEB2;
    --border-color: rgba(255, 255, 255, 0.2);
    --border-heavy: #F3EFE4;
    --accent-primary: #D8C3A5;
    --accent-secondary: #C8B8A0;
    --shadow-color: rgba(0, 0, 0, 0.3);
    --conflict-color: #FF453A;
    --note-color: #AEAEB2; 
}
* { margin: 0; padding: 0; box-sizing: border-box; }
html { 
    font-size: 16px; 
    height: 100%; 
    width: 100%;
    overflow-x: hidden;
}
body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background-color: var(--bg-main);
    color: var(--text-primary);
    line-height: 1.6;
    height: 100%;
    width: 100%;
    position: relative;
    overflow-x: hidden;
    overflow-y: auto;
    transition: background-color 0.4s ease, color 0.4s ease;
    -webkit-overflow-scrolling: touch;
}
.container { 
    width: 100%; 
    height: 100%;
    position: relative; 
    display: flex;
    flex-direction: column;
    overflow-x: hidden;
    overflow-y: auto;
    -webkit-overflow-scrolling: touch;
}
.welcome-screen, .home-screen, .game-screen, .victory-screen {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: flex-start;
    padding: 1rem;
    overflow-y: auto;
    -webkit-overflow-scrolling: touch;
}
.welcome-screen[style*="display: none"], 
.home-screen[style*="display: none"], 
.game-screen[style*="display: none"], 
.victory-screen[style*="display: none"] {
    opacity: 0;
    pointer-events: none;
    transform: scale(0.95);
}
.welcome-content, .home-content, .victory-content {
    background: var(--bg-panel);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border: 1px solid var(--border-color);
    border-radius: 20px;
    padding: 1.5rem;
    box-shadow: 0 8px 32px 0 var(--shadow-color);
    text-align: center;
    width: 100%;
    max-width: 700px;
    margin: auto 0;
}
.game-screen {
    padding-top: 60px; 
}
.game-panel {
    width: 100%;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: 1.5rem;
    padding: 1.5rem;
    background: var(--bg-panel);
    backdrop-filter: blur(12px);
    border-radius: 20px;
    border: 1px solid var(--border-color);
    box-shadow: 0 12px 40px 0 var(--shadow-color);
    max-width: 900px;
    margin: 0 auto;
}
.sudoku-grid-container { 
    width: 100%;
    max-width: min(90vw, 500px);
    margin: 0 auto;
}
.game-controls-container { 
    width: 100%;
    max-width: min(90vw, 500px);
    display: flex; 
    flex-direction: column; 
    gap: 1.5rem;
    margin: 0 auto;
}
.sudoku-grid {
    display: grid;
    grid-template-columns: repeat(9, 1fr);
    grid-template-rows: repeat(9, 1fr);
    border: 3px solid var(--border-heavy);
    border-radius: 8px;
    width: 100%;
    aspect-ratio: 1;
    overflow: hidden;
    margin: 0 auto;
}
.sudoku-cell {
    background-color: var(--bg-cell);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: clamp(0.9rem, 3vw, 1.6rem);
    font-weight: 600;
    cursor: pointer;
    color: var(--text-primary);
    transition: background-color 0.2s ease;
    border-bottom: 1px solid var(--border-color);
    border-right: 1px solid var(--border-color);
    aspect-ratio: 1;
    touch-action: manipulation;
    position: relative; 
}
.notes-container {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    grid-template-rows: repeat(3, 1fr);
    pointer-events: none;
    padding: 2px;
    box-sizing: border-box;
}
.note {
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: clamp(0.4rem, 1.2vw, 0.7rem);
    font-weight: 400;
    color: var(--note-color);
    opacity: 0.8;
    line-height: 1;
    padding: 0;
    margin: 0;
}
@media (max-width: 768px) {
    .note {
        font-size: clamp(0.35rem, 1vw, 0.6rem);
    }
}
.note-mode-btn {
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 0.75rem;
    border-radius: 8px;
    border: 1px solid var(--border-color);
    background-color: var(--bg-element);
    color: var(--text-primary);
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s ease;
    min-height: 44px;
}
.note-mode-btn::after {
    content: attr(title);
    position: absolute;
    bottom: -30px;
    left: 50%;
    transform: translateX(-50%);
    background-color: var(--bg-main);
    color: var(--text-primary);
    padding: 4px 8px;
    border-radius: 4px;
    font-size: 0.75rem;
    white-space: nowrap;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.2s ease, visibility 0.2s ease;
    z-index: 100;
    box-shadow: 0 2px 5px var(--shadow-color);
    border: 1px solid var(--border-color);
    pointer-events: none;
}
.note-mode-btn:hover::after {
    opacity: 1;
    visibility: visible;
}
.note-mode-btn.active {
    background-color: var(--accent-primary);
    color: var(--bg-main);
    border-color: var(--accent-primary);
}
.note-mode-btn:hover {
    transform: translateY(-2px);
    border-color: var(--accent-primary);
    box-shadow: 0 4px 8px var(--shadow-color);
}
.sudoku-cell[data-row="8"] { border-bottom: none; }
.sudoku-cell[data-col="8"] { border-right: none; }
.sudoku-cell[data-row="2"], .sudoku-cell[data-row="5"] {
    border-bottom: 2px solid var(--border-heavy);
}
.sudoku-cell[data-col="2"], .sudoku-cell[data-col="5"] {
    border-right: 2px solid var(--border-heavy);
}
.sudoku-cell:hover { background-color: var(--bg-cell-selected); }
.sudoku-cell.selected { background-color: var(--bg-cell-selected); box-shadow: inset 0 0 0 2px var(--accent-primary); }
.sudoku-cell.prefilled { background-color: transparent; color: var(--text-secondary); cursor: default; font-weight: 700; }
.sudoku-cell.highlight { background-color: var(--bg-element); }
.sudoku-cell.conflict {
    background-color: var(--conflict-color);
    color: white;
    animation: pulse-error 1s ease-in-out;
}
@keyframes pulse-error {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.1); }
}
.game-controls, .number-pad {
    display: grid;
    gap: 0.75rem;
    width: 100%;
}
.game-controls { 
    grid-template-columns: repeat(4, 1fr);
}
.number-pad { 
    grid-template-columns: repeat(5, 1fr);
    margin-top: 1rem;
}
.control-btn, .number-btn, .play-btn, .back-btn, .victory-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 0.75rem;
    border-radius: 8px;
    border: 1px solid var(--border-color);
    background-color: var(--bg-element);
    color: var(--text-primary);
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s ease;
    min-height: 44px; 
}
.control-btn:hover, .number-btn:hover, .play-btn:hover, .back-btn:hover, .victory-btn:hover {
    transform: translateY(-2px);
    border-color: var(--accent-primary);
    box-shadow: 0 4px 8px var(--shadow-color);
}
.number-btn { 
    aspect-ratio: 1; 
    font-size: 1.5rem;
    min-width: 44px;
}
.header { 
    width: 100%; 
    display: flex; 
    justify-content: space-between; 
    align-items: center; 
    padding: 1rem;
    position: fixed; 
    top: 0; 
    left: 0; 
    z-index: 10;
    background-color: var(--bg-panel);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    border-bottom: 1px solid var(--border-color);
}
.difficulty-card:hover { 
    transform: translateY(-5px); 
    background: var(--bg-element); 
    border-color: var(--accent-primary); 
}
.home-header {
    display: flex;
    flex-direction: column;
    align-items: center;
    width: 100%;
    margin-bottom: 2rem;
    position: relative;
    padding-top: 2.5rem; 
}
.back-to-welcome {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 0.5rem 1rem;
    border-radius: 8px;
    border: 1px solid var(--border-color);
    background-color: var(--bg-element);
    color: var(--text-primary);
    font-size: 0.9rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s ease;
    position: absolute;
    left: 0;
    top: 0;
    z-index: 5; 
}
.back-to-welcome:hover {
    transform: translateY(-2px);
    border-color: var(--accent-primary);
    box-shadow: 0 4px 8px var(--shadow-color);
}
.back-to-welcome:active {
    transform: translateY(0);
}
.selection-title { 
    font-size: clamp(1.5rem, 5vw, 2rem);
    text-align: center;
    width: 100%;
}
.difficulty-cards {
    display: grid;
    grid-template-columns: 1fr;
    gap: 1.5rem;
}
@media (min-width: 768px) {
    .difficulty-cards {
        grid-template-columns: repeat(2, 1fr);
    }
}
@media (min-width: 1024px) {
    .difficulty-cards {
        grid-template-columns: repeat(3, 1fr);
    }
}
.difficulty-card {
    background: var(--bg-element);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 1.5rem 1rem;
    text-align: center;
    cursor: pointer;
    transition: all 0.2s ease;
}
.header-right {
    display: flex;
    align-items: center;
    gap: 1rem;
}
.timer-container {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    background-color: var(--bg-element);
    padding: 0.5rem 1rem;
    border-radius: 8px;
}
.theme-toggle {
    background: none;
    border: none;
    color: var(--text-primary);
    font-size: 1.5rem;
    cursor: pointer;
}
.header {
    display: grid;
    grid-template-columns: auto 1fr auto; 
    align-items: center;
    gap: 1rem;
    width: 100%;
    margin-bottom: 1rem;
}
.header-left {
    justify-self: start; 
}
.header-center {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 1rem;
    padding: 0.5rem 1rem;
    background: var(--bg-glass);
    backdrop-filter: blur(10px);
    border-radius: var(--border-radius);
    border: 1px solid var(--border-color);
    min-width: 0; 
}
.header-right {
    justify-self: end; 
}
.timer-section {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}
.difficulty-badge {
    font-size: clamp(0.8rem, 2vw, 0.9rem);
    font-weight: 500;
    padding: 0.2rem 0.6rem;
    border-radius: 1rem;
    background-color: var(--accent-primary-faded);
    color: var(--accent-primary);
    white-space: nowrap; 
}
.timer {
    font-size: clamp(1rem, 3vw, 1.2rem);
    font-weight: 600;
    color: var(--text-primary);
}
.timer-btn {
    background: none;
    border: none;
    font-size: 1.2rem;
    cursor: pointer;
    color: var(--text-secondary);
    padding: 0;
    margin-left: 0.5rem;
    transition: color 0.2s ease, transform 0.2s ease;
    position: relative; 
}
.timer-btn:hover {
    color: var(--text-primary);
    transform: scale(1.1);
}
.timer-btn:active {
    transform: scale(0.95);
}
.timer-btn#restartBtn {
    font-size: 1rem;
}
.game-title {
    font-size: clamp(2.5rem, 8vw, 4rem);
    font-weight: 900;
    margin-bottom: 0.5rem;
}
.game-subtitle {
    font-size: clamp(1rem, 3vw, 1.25rem);
    color: var(--text-secondary);
    margin-bottom: 2rem;
}
.welcome-features {
    display: grid;
    grid-template-columns: 1fr;
    gap: 1rem;
    margin: 2rem 0;
    text-align: left;
}
@media (min-width: 768px) {
    .welcome-features {
        grid-template-columns: repeat(2, 1fr);
    }
}
.feature-item {
    display: flex;
    align-items: center;
    gap: 1rem;
    background: var(--bg-element);
    padding: 1rem;
    border-radius: 12px;
    border: 1px solid var(--border-color);
}
.feature-icon {
    font-size: 1.5rem;
    display: flex;
    align-items: center;
    justify-content: center;
}
.welcome-actions {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin-top: 2rem;
    flex-wrap: wrap;
}
.theme-toggle-welcome {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.75rem;
    padding: 0.75rem 1.5rem;
    border-radius: 8px;
    border: 1px solid var(--border-color);
    background-color: var(--bg-element);
    color: var(--text-primary);
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s ease;
}
.theme-toggle-welcome:hover {
    transform: translateY(-2px);
    border-color: var(--accent-primary);
    box-shadow: 0 4px 8px var(--shadow-color);
}
.welcome-footer {
    margin-top: 2rem;
    font-size: 0.9rem;
    color: var(--text-secondary);
}
.victory-screen {
    padding: 2rem 1rem;
    overflow-y: auto;
    display: flex;
    align-items: center;
    justify-content: center;
    height: 100%;
}
.victory-content {
    background: var(--bg-panel);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border: 1px solid var(--border-color);
    border-radius: 20px;
    padding: 2rem 1.5rem;
    box-shadow: 0 8px 32px 0 var(--shadow-color);
    text-align: center;
    width: 100%;
    max-width: 700px;
    max-height: 90vh;
    overflow-y: auto;
    position: relative;
    margin: 0 auto;
}
.victory-content::before {
    content: '';
    display: block;
    height: 1rem;
}
.victory-message {
    margin-bottom: clamp(1.5rem, 4vw, 2.5rem);
    position: relative;
    z-index: 10;
}
.victory-title {
    font-size: clamp(2rem, 6vw, 3.5rem);
    font-weight: 800;
    margin-bottom: 0.75rem;
    color: var(--accent-primary);
    text-shadow: 0 2px 4px var(--shadow-color);
    position: relative;
    z-index: 10;
    padding-top: 1rem;
}
.victory-subtitle {
    font-size: clamp(1rem, 3vw, 1.4rem);
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
    position: relative;
    z-index: 10;
}
.victory-stats {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: clamp(0.75rem, 2vw, 1.5rem);
    margin-bottom: clamp(1.5rem, 4vw, 2.5rem);
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
    position: relative;
    z-index: 10;
}
@media (min-width: 768px) {
    .victory-stats {
        grid-template-columns: repeat(4, 1fr);
    }
}
.stat-item {
    background: var(--bg-element);
    padding: clamp(0.75rem, 3vw, 1.25rem);
    border-radius: clamp(10px, 2vw, 16px);
    border: 1px solid var(--border-color);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    text-align: center;
}
.stat-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 20px var(--shadow-color);
}
.stat-icon { 
    font-size: 1.5rem;
    margin-bottom: 0.5rem;
}
.stat-label { 
    font-size: 0.9rem; 
    color: var(--text-secondary);
    margin-bottom: 0.25rem;
}
.stat-value { 
    font-size: 1.2rem; 
    font-weight: 600;
}
.victory-actions {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    margin-bottom: 1.5rem;
    position: relative;
    z-index: 10;
}
@media (min-width: 480px) {
    .victory-actions {
        flex-direction: row;
        justify-content: center;
    }
}
.victory-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    padding: 0.75rem 1.5rem;
    border-radius: 8px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s ease;
    background-color: var(--accent-primary);
    color: var(--bg-main);
    border: none;
    flex: 1;
    max-width: 100%;
}
.victory-btn.secondary {
    background-color: var(--bg-element);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
}
.victory-btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 4px 12px var(--shadow-color);
}
@media (min-width: 480px) {
    .victory-btn {
        max-width: 200px;
    }
}
.victory-footer {
    margin-top: 1.5rem;
    font-size: clamp(0.9rem, 2.5vw, 1.1rem);
    color: var(--text-secondary);
    position: relative;
    z-index: 10;
}
.celebration-particles span:nth-child(2) { top: 20%; right: 15%; animation-delay: 0.5s; }
.celebration-particles span:nth-child(3) { bottom: 30%; left: 10%; animation-delay: 1s; }
.celebration-particles span:nth-child(4) { bottom: 20%; right: 20%; animation-delay: 1.5s; }
.celebration-particles span:nth-child(5) { top: 40%; left: 5%; animation-delay: 2s; }
.celebration-particles span:nth-child(6) { top: 60%; right: 5%; animation-delay: 2.5s; }
.confetti-particle {
    pointer-events: none;
    z-index: 5;
}
.celebration-particles span {
    z-index: 5;
}
@keyframes victoryGlow {
    0% { opacity: 0.5; }
    100% { opacity: 1; }
}
@keyframes trophyBounce {
    0%, 100% { transform: translateY(0) scale(1); }
    50% { transform: translateY(-10px) scale(1.05); }
}
@keyframes particleFloat {
    0%, 100% { transform: translateY(0) rotate(0deg); opacity: 0.8; }
    50% { transform: translateY(-20px) rotate(180deg); opacity: 1; }
}
@keyframes titleGlow {
    0% { text-shadow: 0 4px 8px var(--shadow-medium); }
    100% { text-shadow: 0 6px 12px var(--shadow-heavy); }
}
.sudoku-cell,
.number-btn,
.control-btn,
.difficulty-card,
.play-btn,
.theme-toggle,
.back-btn,
.victory-btn {
    will-change: transform;
    backface-visibility: hidden;
    -webkit-backface-visibility: hidden;
}
@media (min-width: 1024px) {
    .game-panel {
        flex-direction: row;
        align-items: flex-start;
    }
    .sudoku-grid-container {
        flex: 3;
        max-width: 500px;
    }
    .game-controls-container {
        flex: 2;
        max-width: 300px;
    }
    .game-controls {
        grid-template-columns: repeat(2, 1fr);
    }
    .number-pad {
        grid-template-columns: repeat(3, 1fr);
    }
}
@media (min-width: 768px) and (max-width: 1023px) {
    .game-panel {
        padding: 1.5rem;
        max-width: 700px;
    }
    .sudoku-grid-container {
        max-width: 450px;
    }
    .game-controls-container {
        max-width: 450px;
    }
    .sudoku-cell {
        font-size: clamp(1rem, 2.5vw, 1.4rem);
    }
}
@media (max-width: 767px) {
    .welcome-content, .home-content, .victory-content, .game-panel {
        padding: 1rem;
        border-radius: 15px;
    }
    .header {
        padding: 0.75rem;
    }
    .sudoku-grid {
        border-width: 2px;
    }
    .sudoku-cell {
        font-size: clamp(0.8rem, 4vw, 1.2rem);
    }
    .number-pad {
        gap: 0.5rem;
    }
    .number-btn {
        font-size: 1.2rem;
        padding: 0.5rem;
    }
    .control-btn {
        font-size: 0.9rem;
        padding: 0.5rem;
    }
    .game-controls {
        grid-template-columns: repeat(2, 1fr);
    }
}
@media (max-width: 359px) {
    .welcome-content, .home-content, .victory-content, .game-panel {
        padding: 0.75rem;
        border-radius: 10px;
    }
    .header {
        padding: 0.5rem;
    }
    .sudoku-cell {
        font-size: clamp(0.7rem, 3.5vw, 1rem);
    }
    .number-pad {
        gap: 0.3rem;
    }
    .number-btn {
        font-size: 1rem;
        padding: 0.3rem;
        min-height: 36px;
    }
    .control-btn {
        font-size: 0.8rem;
        padding: 0.3rem;
        min-height: 36px;
    }
}
@media (max-height: 600px) and (orientation: landscape) {
    .game-screen {
        padding-top: 50px;
    }
    .header {
        padding: 0.5rem 1rem;
    }
    .game-panel {
        flex-direction: row;
        align-items: flex-start;
        padding: 1rem;
        margin: 0.5rem auto;
        max-height: calc(100vh - 60px);
        overflow-y: auto;
    }
    .sudoku-grid-container {
        flex: 1;
        max-width: 45%;
    }
    .game-controls-container {
        flex: 1;
        max-width: 45%;
    }
    .game-controls {
        grid-template-columns: repeat(2, 1fr);
    }
    .number-pad {
        grid-template-columns: repeat(5, 1fr);
    }
    .sudoku-cell {
        font-size: clamp(0.7rem, 2.5vw, 1.2rem);
    }
}
@media (hover: none) and (pointer: coarse) {
    .sudoku-cell,
    .control-btn,
    .number-btn,
    .play-btn,
    .back-btn,
    .victory-btn {
        cursor: default;
        -webkit-tap-highlight-color: transparent;
    }
    .sudoku-cell:hover {
        background-color: var(--bg-cell);
    }
    .sudoku-cell:active {
        background-color: var(--bg-cell-selected);
    }
}
@media (prefers-contrast: high) {
    :root {
        --border-heavy: #000000;
        --conflict-color: #FF0000;
    }
    [data-theme="dark"] {
        --border-heavy: #FFFFFF;
        --conflict-color: #FF6B6B;
    }
    .sudoku-cell {
        border-width: 1px;
    }
    .sudoku-cell[data-row="2"], 
    .sudoku-cell[data-row="5"],
    .sudoku-cell[data-col="2"], 
    .sudoku-cell[data-col="5"] {
        border-width: 3px;
    }
}
@media (prefers-reduced-motion: reduce) {
    * {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.1s !important;
    }
    .sudoku-cell:hover,
    .difficulty-card:hover,
    .play-btn:hover,
    .number-btn:hover,
    .victory-btn:hover {
        transform: none !important;
    }
    .trophy-icon,
    .celebration-particles span {
        animation: none !important;
    }
}
@media print {
    .header,
    .game-controls,
    .input-section,
    .welcome-actions,
    .theme-toggle,
    .theme-toggle-welcome,
    .victory-actions,
    .victory-toast {
        display: none !important;
    }
    .sudoku-grid {
        box-shadow: none !important;
        border: 2px solid #000 !important;
    }
    .sudoku-cell {
        border: 1px solid #000 !important;
        background: white !important;
        color: black !important;
    }
    .victory-content {
        background: var(--bg-primary) !important;
        color: var(--text-primary) !important;
        box-shadow: none !important;
    }
}
.victory-toast {
    position: fixed;
    top: 20px;
    right: 20px;
    z-index: 1000;
    background: var(--bg-primary);
    border: 3px solid var(--button-primary);
    border-radius: clamp(12px, 3vw, 16px);
    box-shadow: 0 12px 32px var(--shadow-heavy);
    max-width: min(400px, 90vw);
    transform: translateX(100%);
    opacity: 0;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    will-change: transform, opacity;
}
.victory-toast.show {
    transform: translateX(0);
    opacity: 1;
}
.toast-content {
    padding: clamp(1rem, 3vw, 1.5rem);
    display: flex;
    align-items: flex-start;
    gap: clamp(0.75rem, 2vw, 1rem);
    position: relative;
}
.toast-icon {
    font-size: clamp(1.5rem, 4vw, 2rem);
    flex-shrink: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    animation: bounce 1s ease-in-out infinite alternate;
}
.toast-text {
    flex: 1;
    min-width: 0;
}
.toast-title {
    font-size: clamp(1rem, 3vw, 1.2rem);
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: clamp(0.25rem, 1vw, 0.5rem);
    line-height: 1.2;
}
.toast-subtitle {
    font-size: clamp(0.8rem, 2.5vw, 0.9rem);
    color: var(--text-secondary);
    margin-bottom: clamp(0.75rem, 2vw, 1rem);
}
.toast-actions {
    display: flex;
    gap: clamp(0.5rem, 1.5vw, 0.75rem);
    flex-wrap: wrap;
}
.toast-btn {
    padding: clamp(0.4rem, 1.5vw, 0.6rem) clamp(0.75rem, 2vw, 1rem);
    border-radius: clamp(6px, 1.5vw, 8px);
    font-size: clamp(0.7rem, 2vw, 0.8rem);
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s ease;
    border: none;
    white-space: nowrap;
    touch-action: manipulation;
}
.toast-btn.primary {
    background: var(--button-primary);
    color: white;
}
.toast-btn.secondary {
    background: var(--bg-secondary);
    color: var(--text-primary);
    border: 1px solid var(--border-medium);
}
.toast-btn:hover, .toast-btn:active {
    transform: translateY(-1px);
    box-shadow: 0 2px 8px var(--shadow-medium);
}
.toast-close {
    position: absolute;
    top: clamp(0.5rem, 1vw, 0.75rem);
    right: clamp(0.5rem, 1vw, 0.75rem);
    background: none;
    border: none;
    font-size: clamp(1rem, 3vw, 1.2rem);
    color: var(--text-muted);
    cursor: pointer;
    width: clamp(20px, 4vw, 24px);
    height: clamp(20px, 4vw, 24px);
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    transition: all 0.2s ease;
    touch-action: manipulation;
}
.toast-close:hover, .toast-close:active {
    background: var(--bg-hover);
    color: var(--text-primary);
}
@keyframes bounce {
    0% { transform: translateY(0); }
    100% { transform: translateY(-4px); }
}
@media (max-width: 768px) {
    .victory-toast {
        top: 10px;
        right: 10px;
        left: 10px;
        max-width: none;
    }
    .toast-content {
        flex-direction: column;
        align-items: center;
        text-align: center;
        gap: clamp(0.5rem, 2vw, 0.75rem);
    }
    .toast-actions {
        justify-content: center;
        width: 100%;
    }
    .toast-btn {
        flex: 1;
        min-width: clamp(80px, 20vw, 100px);
    }
}
@keyframes fall {
    0% {
        transform: translateY(0) rotate(0deg);
        opacity: 0;
    }
    10% {
        opacity: 0.7;
    }
    100% {
        transform: translateY(500px) rotate(720deg);
        opacity: 0;
    }
}
@keyframes pulse {
    0% { transform: scale(1); }
    50% { transform: scale(1.1); }
    100% { transform: scale(1); }
}
.confetti-particle {
    pointer-events: none;
}
.confetti-particle i {
    display: block;
    transform-origin: center;
}
.victory-content {
    position: relative;
    overflow: hidden;
}
.note-mode-indicator {
    display: none;
    font-size: clamp(0.8rem, 2vw, 0.9rem);
    font-weight: 500;
    padding: 0.2rem 0.6rem;
    border-radius: 1rem;
    background-color: var(--accent-primary);
    color: var(--bg-main);
    white-space: nowrap;
    margin-left: 0.5rem;
}
.note-mode-indicator.active {
    display: inline-block;
    animation: pulse 1.5s infinite alternate;
}
@keyframes pulse {
    0% { opacity: 0.7; }
    100% { opacity: 1; }
}
.sudoku-grid.paused {
    filter: blur(5px);
    pointer-events: none;
}
.sudoku-grid-container {
    position: relative;
    width: 100%;
    max-width: min(90vw, 500px);
    margin: 0 auto;
}
.pause-overlay {
    display: none;
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    font-size: clamp(2rem, 5vw, 3rem);
    font-weight: 700;
    color: var(--accent-primary);
    text-shadow: 0 2px 4px var(--shadow-color);
    z-index: 10;
    pointer-events: none;
    background-color: rgba(0, 0, 0, 0.2);
    padding: 0.5rem 1.5rem;
    border-radius: 10px;
    border: 2px solid var(--accent-primary);
}
.sudoku-grid.paused + .pause-overlay {
    display: block;
}
.timer-btn[title]::after {
    content: attr(title);
    position: absolute;
    bottom: -25px;
    left: 50%;
    transform: translateX(-50%);
    background-color: var(--bg-main);
    color: var(--text-primary);
    padding: 4px 8px;
    border-radius: 4px;
    font-size: 0.75rem;
    white-space: nowrap;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.2s ease, visibility 0.2s ease;
    z-index: 100;
    box-shadow: 0 2px 5px var(--shadow-color);
    border: 1px solid var(--border-color);
    pointer-events: none;
}
.timer-btn[title]:hover::after {
    opacity: 1;
    visibility: visible;
}
.stat-item:nth-child(4) .stat-icon {
    color: var(--conflict-color);
}
#mistakesCount {
    font-weight: 700;
}
.stat-item:nth-child(4).perfect .stat-icon {
    color: #4CAF50;
}
.stat-item:nth-child(4).perfect .stat-value {
    color: #4CAF50;
}
@keyframes mistake-flash {
    0%, 100% { background-color: var(--bg-cell); }
    50% { background-color: var(--conflict-color); color: white; }
}
.sudoku-cell.mistake {
    animation: mistake-flash 0.5s ease;
}
.feature-icon i, 
.card-icon i, 
.stat-icon i, 
.btn-icon i,
.toast-icon i,
.theme-icon i,
.play-icon i {
    font-size: 1.2em;
    width: 1.25em;
    height: 1.25em;
    display: flex;
    align-items: center;
    justify-content: center;
}
.feature-icon {
    font-size: 1.5rem;
    display: flex;
    align-items: center;
    justify-content: center;
}
.card-icon {
    font-size: 2rem;
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    justify-content: center;
}
.stat-icon {
    font-size: clamp(1.5rem, 4vw, 2rem);
    margin-bottom: clamp(0.5rem, 1vw, 0.75rem);
    display: flex;
    align-items: center;
    justify-content: center;
}
.toast-icon {
    font-size: clamp(1.5rem, 4vw, 2rem);
    flex-shrink: 0;
    display: flex;
    align-items: center;
    justify-content: center;
}
.timer-btn i {
    font-size: 1em;
}
.number-btn.delete-btn i {
    font-size: 0.8em;
}
.confirmation-dialog-container {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.3s ease, visibility 0.3s ease;
}
.confirmation-dialog-container.show {
    opacity: 1;
    visibility: visible;
}
.confirmation-dialog {
    background-color: var(--bg-main);
    border-radius: 12px;
    padding: 1.5rem;
    width: 90%;
    max-width: 400px;
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.2);
    transform: scale(0.9);
    transition: transform 0.3s ease;
}
.confirmation-dialog-container.show .confirmation-dialog {
    transform: scale(1);
}
.dialog-title {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
    color: var(--text-primary);
}
.dialog-message {
    font-size: 1rem;
    margin-bottom: 1.5rem;
    color: var(--text-secondary);
    line-height: 1.5;
}
.dialog-buttons {
    display: flex;
    justify-content: flex-end;
    gap: 1rem;
}
.dialog-btn {
    padding: 0.75rem 1.5rem;
    border-radius: 8px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s ease;
    border: none;
}
.dialog-btn.cancel {
    background-color: var(--bg-element);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
}
.dialog-btn.confirm {
    background-color: var(--accent-primary);
    color: var(--bg-main);
}
.dialog-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 8px var(--shadow-color);
}
.dialog-btn:active {
    transform: translateY(0);
}
@media (min-width: 768px) {
    .victory-screen {
        padding: 1rem;
    }
    .victory-content {
        padding: 2.5rem;
    }
    .victory-title {
        padding-top: 0;
    }
}
@media (min-width: 768px) {
    .home-header {
        padding-top: 0;
        flex-direction: row;
        justify-content: center;
    }
    .back-to-welcome {
        position: absolute;
        left: 0;
        top: 50%;
        transform: translateY(-50%);
    }
    .selection-title {
        margin: 0;
    }
}
.note span {
    display: block;
    width: 100%;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
}