/* ========================================
   SUDOKU NOVA - Cosmic Theme Styles
   ======================================== */

:root {
    /* Cosmic Color Palette */
    --bg-deep: #0a0a1a;
    --bg-mid: #12122a;
    --bg-surface: #1a1a3a;
    
    --nova-pink: #ff2d75;
    --nova-purple: #9d4edd;
    --nova-blue: #4cc9f0;
    --nova-cyan: #00f5d4;
    --nova-gold: #ffd700;
    --nova-orange: #ff6b35;
    
    --text-primary: #ffffff;
    --text-secondary: rgba(255, 255, 255, 0.7);
    --text-dim: rgba(255, 255, 255, 0.4);
    
    --glow-pink: 0 0 20px rgba(255, 45, 117, 0.5);
    --glow-purple: 0 0 20px rgba(157, 78, 221, 0.5);
    --glow-blue: 0 0 20px rgba(76, 201, 240, 0.5);
    --glow-cyan: 0 0 20px rgba(0, 245, 212, 0.5);
    --glow-gold: 0 0 20px rgba(255, 215, 0, 0.5);
    
    /* Grid Colors */
    --cell-bg: rgba(255, 255, 255, 0.03);
    --cell-bg-hover: rgba(255, 255, 255, 0.08);
    --cell-bg-selected: rgba(76, 201, 240, 0.25);
    --cell-bg-same-number: rgba(157, 78, 221, 0.25);
    --cell-bg-same-region: rgba(76, 201, 240, 0.08);
    --cell-border: rgba(255, 255, 255, 0.1);
    --cell-border-box: rgba(255, 255, 255, 0.3);
    --cell-error: rgba(255, 45, 117, 0.3);
    
    /* Sizing */
    --grid-size: min(92vw, 390px);
    --cell-size: calc(var(--grid-size) / 9);
    
    /* Transitions */
    --transition-fast: 0.15s ease;
    --transition-medium: 0.3s ease;
    --transition-slow: 0.5s ease;
}

/* Reset & Base */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html, body {
    height: 100%;
    overflow: hidden;
    position: fixed;
    width: 100%;
}

body {
    font-family: 'DM Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    background: var(--bg-deep);
    color: var(--text-primary);
    display: flex;
    justify-content: center;
    align-items: flex-start;
    min-height: 100vh;
    min-height: 100dvh;
    min-height: -webkit-fill-available;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    touch-action: manipulation;
    user-select: none;
    -webkit-user-select: none;
}

/* Particle Background */
#particles {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 0;
    pointer-events: none;
}

/* App Container */
#app {
    position: relative;
    z-index: 1;
    width: 100%;
    max-width: 430px;
    min-height: 100vh;
    min-height: 100dvh;
    min-height: -webkit-fill-available;
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 12px 16px;
    padding-top: calc(env(safe-area-inset-top, 0px) + 12px);
    padding-bottom: calc(env(safe-area-inset-bottom, 0px) + 12px);
    background: linear-gradient(
        180deg,
        rgba(157, 78, 221, 0.1) 0%,
        transparent 30%,
        transparent 70%,
        rgba(76, 201, 240, 0.1) 100%
    );
}

/* Header */
.game-header {
    width: 100%;
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 8px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 8px;
}

.logo-icon {
    font-size: 24px;
    animation: pulse-glow 2s ease-in-out infinite;
    display: flex;
    align-items: center;
}

.logo-icon svg {
    width: 24px;
    height: 24px;
    color: var(--nova-pink);
    filter: drop-shadow(0 0 8px rgba(255, 45, 117, 0.6));
}

.logo-text {
    font-family: 'Outfit', -apple-system, sans-serif;
    font-size: 20px;
    font-weight: 700;
    letter-spacing: 1px;
    background: linear-gradient(135deg, var(--nova-pink), var(--nova-purple), var(--nova-blue));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.header-stats {
    display: flex;
    align-items: center;
    gap: 12px;
}

/* Sound Toggle */
.sound-toggle {
    background: var(--bg-surface);
    border: 1px solid var(--cell-border);
    border-radius: 8px;
    padding: 8px;
    cursor: pointer;
    transition: all var(--transition-fast);
    display: flex;
    align-items: center;
    justify-content: center;
}

.sound-toggle:hover {
    border-color: var(--nova-cyan);
    box-shadow: var(--glow-cyan);
}

.sound-toggle:active {
    transform: scale(0.95);
}

.sound-icon {
    width: 18px;
    height: 18px;
    color: var(--nova-cyan);
    filter: drop-shadow(0 0 4px rgba(76, 201, 240, 0.5));
}

.sound-toggle .sound-off {
    display: none;
    color: var(--text-dim);
    filter: none;
}

.sound-toggle.muted .sound-on {
    display: none;
}

.sound-toggle.muted .sound-off {
    display: block;
}

.sound-toggle.muted {
    opacity: 0.6;
}

/* Sound wave animation */
.sound-wave {
    stroke-linecap: round;
}

.sound-toggle:not(.muted) .wave-1 {
    animation: sound-pulse 1.5s ease-in-out infinite;
}

.sound-toggle:not(.muted) .wave-2 {
    animation: sound-pulse 1.5s ease-in-out infinite 0.2s;
}

@keyframes sound-pulse {
    0%, 100% { opacity: 0.4; }
    50% { opacity: 1; }
}

.stat {
    display: flex;
    align-items: center;
    gap: 4px;
    font-weight: 600;
}

.stat-icon {
    font-size: 16px;
    display: flex;
    align-items: center;
}

.stat-icon svg {
    width: 16px;
    height: 16px;
}

.stat.streak .stat-icon svg {
    color: var(--nova-orange);
    filter: drop-shadow(0 0 4px rgba(255, 107, 53, 0.6));
}

.stat.level .stat-icon svg {
    color: var(--nova-gold);
    fill: var(--nova-gold);
    filter: drop-shadow(0 0 4px rgba(255, 215, 0, 0.6));
}

.stat-value {
    font-family: 'Outfit', -apple-system, sans-serif;
    font-size: 14px;
}

/* Stats Bar */
.stats-bar {
    width: 100%;
    display: flex;
    justify-content: space-between;
    padding: 10px 16px;
    background: var(--bg-surface);
    border-radius: 12px;
    margin-bottom: 8px;
    border: 1px solid var(--cell-border);
}

.stat-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 2px;
}

.stat-label {
    font-size: 10px;
    color: var(--text-dim);
    letter-spacing: 1px;
    font-weight: 500;
}

.stat-number {
    font-family: 'Outfit', -apple-system, sans-serif;
    font-size: 16px;
    font-weight: 600;
}

.combo-container {
    position: relative;
}

.combo-display {
    color: var(--nova-gold);
    transition: var(--transition-fast);
}

.combo-display.active {
    transform: scale(1.2);
    text-shadow: var(--glow-gold);
    animation: combo-pulse 0.5s ease infinite;
}

@keyframes combo-pulse {
    0%, 100% { 
        text-shadow: 0 0 10px rgba(255, 215, 0, 0.5);
    }
    50% { 
        text-shadow: 0 0 20px rgba(255, 215, 0, 0.8), 0 0 30px rgba(255, 215, 0, 0.5);
    }
}

/* Combo Timer Bar */
.combo-timer-bar {
    position: absolute;
    bottom: -8px;
    left: 50%;
    transform: translateX(-50%);
    width: 40px;
    height: 3px;
    background: var(--bg-deep);
    border-radius: 2px;
    overflow: hidden;
    opacity: 0;
    transition: opacity 0.3s ease;
}

.combo-timer-bar.active {
    opacity: 1;
}

.combo-timer-fill {
    height: 100%;
    width: 100%;
    background: linear-gradient(90deg, var(--nova-gold), var(--nova-orange));
    border-radius: 2px;
    transform-origin: left;
    box-shadow: 0 0 8px rgba(255, 215, 0, 0.6);
}

.combo-timer-bar.warning .combo-timer-fill {
    background: linear-gradient(90deg, var(--nova-orange), var(--nova-pink));
    animation: bar-warning 0.3s ease infinite;
}

@keyframes bar-warning {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.6; }
}

/* XP Bar */
.xp-bar-container {
    width: 100%;
    margin-bottom: 10px;
    display: flex;
    align-items: center;
    gap: 10px;
}

.xp-bar {
    flex: 1;
    height: 6px;
    background: var(--bg-surface);
    border-radius: 3px;
    overflow: hidden;
    border: 1px solid var(--cell-border);
}

.xp-fill {
    height: 100%;
    width: 0%;
    background: linear-gradient(90deg, var(--nova-purple), var(--nova-pink));
    border-radius: 3px;
    transition: width 0.5s ease;
    box-shadow: var(--glow-pink);
}

.xp-text {
    font-size: 11px;
    color: var(--text-secondary);
    font-weight: 500;
    min-width: 80px;
    text-align: right;
}

/* Grid Container */
.grid-container {
    position: relative;
    margin-bottom: 12px;
    z-index: 1;
}

.grid-glow {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: calc(var(--grid-size) + 40px);
    height: calc(var(--grid-size) + 40px);
    background: radial-gradient(
        circle,
        rgba(157, 78, 221, 0.15) 0%,
        rgba(76, 201, 240, 0.1) 50%,
        transparent 70%
    );
    border-radius: 20px;
    pointer-events: none;
    animation: grid-glow-pulse 4s ease-in-out infinite;
}

/* Sudoku Grid */
.sudoku-grid {
    display: grid;
    grid-template-columns: repeat(9, var(--cell-size));
    grid-template-rows: repeat(9, var(--cell-size));
    background: var(--bg-mid);
    border: 2px solid var(--cell-border-box);
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 
        0 4px 30px rgba(0, 0, 0, 0.5),
        inset 0 0 60px rgba(157, 78, 221, 0.05);
}

.cell {
    display: flex;
    justify-content: center;
    align-items: center;
    background: var(--cell-bg);
    border: 1px solid var(--cell-border);
    font-family: 'DM Sans', -apple-system, BlinkMacSystemFont, sans-serif;
    font-size: calc(var(--cell-size) * 0.55);
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-fast);
    position: relative;
    overflow: hidden;
}

/* Box borders (3x3 sections) */
.cell:nth-child(3n) {
    border-right-color: var(--cell-border-box);
}

.cell:nth-child(n+19):nth-child(-n+27),
.cell:nth-child(n+46):nth-child(-n+54) {
    border-bottom-color: var(--cell-border-box);
}

.cell:nth-child(9n+1) {
    border-left-color: transparent;
}

.cell:nth-child(-n+9) {
    border-top-color: transparent;
}

/* Cell States */
.cell:hover:not(.fixed) {
    background: var(--cell-bg-hover);
}

.cell.selected {
    background: var(--cell-bg-selected);
    box-shadow: inset 0 0 15px rgba(76, 201, 240, 0.3);
}

.cell.same-number {
    background: var(--cell-bg-same-number);
}

.cell.same-region {
    background: var(--cell-bg-same-region);
}

.cell.fixed {
    color: var(--text-primary);
    font-weight: 500;
}

.cell:not(.fixed) {
    color: var(--nova-cyan);
    font-weight: 600;
}

.cell.error {
    background: var(--cell-error);
    animation: shake 0.3s ease;
}

.cell.error:not(.fixed) {
    color: var(--nova-pink);
}

/* Notes/Pencil Marks */
.cell .notes {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    grid-template-rows: repeat(3, 1fr);
    width: 100%;
    height: 100%;
    padding: 2px;
}

.cell .notes span {
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: calc(var(--cell-size) * 0.22);
    color: var(--text-dim);
    font-weight: 400;
}

/* Blast Animation */
.cell.blast {
    animation: blast-cell 0.6s ease forwards;
}

.cell.blast::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle, rgba(255, 215, 0, 0.8) 0%, transparent 70%);
    transform: translate(-50%, -50%) scale(0);
    animation: blast-wave 0.6s ease forwards;
    pointer-events: none;
}

/* Correct Placement Animation */
.cell.correct-place {
    animation: correct-bounce 0.4s ease;
}

/* Blast Overlay */
.blast-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: 10;
}

/* Power-ups */
.powerups {
    display: flex;
    gap: 12px;
    margin-bottom: 12px;
}

.powerup {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 4px;
    padding: 10px 16px;
    background: var(--bg-surface);
    border: 1px solid var(--cell-border);
    border-radius: 12px;
    cursor: pointer;
    transition: all var(--transition-fast);
    position: relative;
}

.powerup:active {
    transform: scale(0.95);
}

.powerup:hover {
    border-color: var(--nova-purple);
    box-shadow: var(--glow-purple);
}

.powerup.disabled {
    opacity: 0.4;
    pointer-events: none;
}

.powerup-icon {
    font-size: 24px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.powerup-icon svg {
    width: 24px;
    height: 24px;
}

#powerup-hint .powerup-icon svg {
    color: var(--nova-gold);
    filter: drop-shadow(0 0 6px rgba(255, 215, 0, 0.5));
}

#powerup-freeze .powerup-icon svg {
    color: var(--nova-cyan);
    filter: drop-shadow(0 0 6px rgba(0, 245, 212, 0.5));
}

#powerup-blast .powerup-icon svg {
    color: var(--nova-orange);
    filter: drop-shadow(0 0 6px rgba(255, 107, 53, 0.5));
}

.powerup-name {
    font-size: 10px;
    color: var(--text-secondary);
    font-weight: 500;
    letter-spacing: 0.5px;
}

.powerup-count {
    position: absolute;
    top: -6px;
    right: -6px;
    width: 20px;
    height: 20px;
    background: linear-gradient(135deg, var(--nova-pink), var(--nova-purple));
    border-radius: 50%;
    font-family: 'Outfit', -apple-system, sans-serif;
    font-size: 11px;
    font-weight: 700;
    display: flex;
    justify-content: center;
    align-items: center;
    box-shadow: var(--glow-pink);
}

/* Number Pad */
.number-pad {
    display: grid;
    grid-template-columns: repeat(9, 1fr);
    gap: 0;
    width: 100%;
    max-width: calc(var(--grid-size) + 20px);
    margin-bottom: 10px;
    padding: 4px 0;
}

.num-btn {
    display: flex;
    justify-content: center;
    align-items: center;
    background: transparent;
    border: none;
    border-radius: 12px;
    font-family: 'DM Sans', -apple-system, sans-serif;
    font-size: 28px;
    font-weight: 600;
    color: var(--text-primary);
    cursor: pointer;
    transition: all var(--transition-fast);
    padding: 14px 0;
    min-height: 56px;
}

.num-btn:active {
    transform: scale(0.85);
    color: var(--nova-cyan);
}

.num-btn:hover {
    color: var(--nova-blue);
    background: rgba(76, 201, 240, 0.1);
}

.num-btn.completed {
    opacity: 0.25;
    color: var(--text-dim);
}

.num-btn.highlighted {
    color: var(--nova-cyan);
    text-shadow: 0 0 20px rgba(76, 201, 240, 0.8);
}

/* Number Complete Celebration */
.num-btn.number-complete-flash {
    animation: number-complete 0.8s ease-out;
    opacity: 1 !important;
    color: var(--nova-gold) !important;
}

@keyframes number-complete {
    0% {
        transform: scale(1);
        text-shadow: 0 0 0 transparent;
    }
    30% {
        transform: scale(1.3);
        text-shadow: 0 0 30px rgba(255, 215, 0, 1), 0 0 60px rgba(255, 215, 0, 0.8);
    }
    60% {
        transform: scale(1.1);
    }
    100% {
        transform: scale(1);
        text-shadow: 0 0 10px rgba(255, 215, 0, 0.5);
    }
}

/* Action Buttons */
.action-buttons {
    display: flex;
    gap: 10px;
    width: 100%;
    max-width: var(--grid-size);
}

.action-btn {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 3px;
    padding: 10px 8px;
    background: var(--bg-surface);
    border: 1px solid var(--cell-border);
    border-radius: 12px;
    color: var(--text-secondary);
    font-size: 11px;
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.action-btn .action-icon {
    display: flex;
    align-items: center;
    justify-content: center;
}

.action-btn .action-icon svg {
    width: 20px;
    height: 20px;
}

.action-btn:active {
    transform: scale(0.95);
}

.action-btn:hover {
    background: var(--cell-bg-hover);
    border-color: var(--nova-purple);
}

.action-btn.active {
    background: rgba(157, 78, 221, 0.2);
    border-color: var(--nova-purple);
    color: var(--nova-purple);
}

/* Modals */
.modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.85);
    backdrop-filter: blur(10px);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 100;
    opacity: 0;
    pointer-events: none;
    transition: opacity var(--transition-medium);
}

.modal.active {
    opacity: 1;
    pointer-events: all;
}

.modal-content {
    background: var(--bg-mid);
    border: 1px solid var(--cell-border-box);
    border-radius: 20px;
    padding: 32px 24px;
    max-width: 90%;
    width: 380px;
    text-align: center;
    transform: scale(0.9);
    transition: transform var(--transition-medium);
    box-shadow: 
        0 20px 60px rgba(0, 0, 0, 0.5),
        0 0 40px rgba(157, 78, 221, 0.2);
}

.modal.active .modal-content {
    transform: scale(1);
}

.modal-content h2 {
    font-family: 'Outfit', -apple-system, sans-serif;
    font-size: 20px;
    font-weight: 700;
    letter-spacing: 1px;
    margin-bottom: 24px;
    background: linear-gradient(135deg, var(--nova-pink), var(--nova-purple));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

/* Modal Tabs */
.modal-tabs {
    display: flex;
    gap: 4px;
    margin-bottom: 20px;
    background: var(--bg-deep);
    padding: 4px;
    border-radius: 10px;
}

.modal-tab {
    flex: 1;
    padding: 10px 16px;
    background: transparent;
    border: none;
    border-radius: 8px;
    font-family: 'Outfit', -apple-system, sans-serif;
    font-size: 11px;
    font-weight: 600;
    letter-spacing: 1px;
    color: var(--text-dim);
    cursor: pointer;
    transition: all var(--transition-fast);
}

.modal-tab:hover {
    color: var(--text-secondary);
}

.modal-tab.active {
    background: linear-gradient(135deg, var(--nova-pink), var(--nova-purple));
    color: white;
    box-shadow: var(--glow-pink);
}

/* Tab Content */
.tab-content {
    display: none;
}

.tab-content.active {
    display: block;
}

.difficulty-modal-content {
    max-height: 85vh;
    overflow: hidden;
    display: flex;
    flex-direction: column;
}

.difficulty-modal-content h2 {
    margin-bottom: 16px;
}

/* How to Play Styles */
.howto-scroll {
    max-height: 55vh;
    overflow-y: auto;
    padding-right: 8px;
    scrollbar-width: thin;
    scrollbar-color: var(--nova-purple) var(--bg-deep);
}

.howto-scroll::-webkit-scrollbar {
    width: 6px;
}

.howto-scroll::-webkit-scrollbar-track {
    background: var(--bg-deep);
    border-radius: 3px;
}

.howto-scroll::-webkit-scrollbar-thumb {
    background: var(--nova-purple);
    border-radius: 3px;
}

.howto-section {
    margin-bottom: 20px;
    text-align: left;
}

.howto-section h3 {
    font-family: 'Outfit', -apple-system, sans-serif;
    font-size: 14px;
    font-weight: 600;
    color: var(--nova-cyan);
    margin-bottom: 10px;
    padding-bottom: 6px;
    border-bottom: 1px solid var(--cell-border);
    display: flex;
    align-items: center;
    gap: 8px;
}

.howto-section h3 svg {
    width: 16px;
    height: 16px;
}

.howto-section p {
    font-size: 13px;
    color: var(--text-secondary);
    line-height: 1.5;
    margin-bottom: 8px;
}

.howto-section strong {
    color: var(--text-primary);
}

.howto-item {
    display: flex;
    gap: 12px;
    align-items: flex-start;
    margin-bottom: 12px;
    padding: 10px;
    background: var(--bg-deep);
    border-radius: 10px;
    border: 1px solid var(--cell-border);
}

.howto-item:last-child {
    margin-bottom: 0;
}

.howto-icon {
    min-width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 18px;
    background: var(--bg-surface);
    border-radius: 8px;
}

.howto-icon svg {
    width: 18px;
    height: 18px;
}

.howto-icon.highlight {
    font-size: 11px;
    font-family: 'Outfit', -apple-system, sans-serif;
    font-weight: 700;
    background: linear-gradient(135deg, var(--nova-gold), var(--nova-orange));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.howto-icon.warning {
    color: var(--nova-pink);
}

.howto-icon.powerup-hint {
    background: linear-gradient(135deg, rgba(255, 215, 0, 0.2), rgba(255, 215, 0, 0.1));
}

.howto-icon.powerup-hint svg {
    color: var(--nova-gold);
}

.howto-icon.powerup-freeze {
    background: linear-gradient(135deg, rgba(76, 201, 240, 0.2), rgba(76, 201, 240, 0.1));
}

.howto-icon.powerup-freeze svg {
    color: var(--nova-cyan);
}

.howto-icon.powerup-blast {
    background: linear-gradient(135deg, rgba(255, 107, 53, 0.2), rgba(255, 45, 117, 0.1));
}

.howto-icon.powerup-blast svg {
    color: var(--nova-orange);
}

.howto-item div {
    flex: 1;
}

.howto-item strong {
    display: block;
    font-size: 13px;
    color: var(--text-primary);
    margin-bottom: 2px;
}

.howto-item p {
    font-size: 12px;
    color: var(--text-dim);
    margin: 0;
    line-height: 1.4;
}

/* Star Ratings */
.star-ratings {
    margin: 12px 0;
}

.star-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 8px 12px;
    background: var(--bg-deep);
    border-radius: 8px;
    margin-bottom: 6px;
    font-size: 12px;
}

.star-row span:first-child,
.star-row .star-icons {
    min-width: 60px;
    display: flex;
    gap: 2px;
}

.star-row .star-icons svg {
    width: 14px;
    height: 14px;
    color: var(--nova-gold);
    fill: var(--nova-gold);
}

.star-row span:last-child {
    color: var(--text-secondary);
    text-align: right;
}

.target-times {
    font-size: 11px !important;
    color: var(--text-dim) !important;
    font-style: italic;
    margin-top: 8px;
}

/* Tips List */
.tips-list {
    list-style: none;
    padding: 0;
    margin: 0;
}

.tips-list li {
    position: relative;
    padding: 8px 0 8px 24px;
    font-size: 12px;
    color: var(--text-secondary);
    border-bottom: 1px solid var(--cell-border);
}

.tips-list li:last-child {
    border-bottom: none;
}

.tips-list li::before {
    content: '→';
    position: absolute;
    left: 0;
    color: var(--nova-cyan);
    font-weight: bold;
}

.tips-list li strong {
    color: var(--nova-purple);
}

/* Stats Tab */
.stats-grid {
    display: flex;
    flex-direction: column;
    gap: 16px;
    padding: 8px 0;
}

.stats-card {
    background: var(--bg-surface);
    border: 1px solid var(--cell-border);
    border-radius: 12px;
    padding: 16px;
}

.stats-card.stats-overview {
    background: linear-gradient(135deg, rgba(157, 78, 221, 0.15), rgba(76, 201, 240, 0.1));
    border-color: var(--nova-purple);
}

.stats-card-header {
    display: flex;
    align-items: center;
    gap: 8px;
    margin-bottom: 12px;
    padding-bottom: 8px;
    border-bottom: 1px solid var(--cell-border);
}

.stats-card-header svg {
    width: 18px;
    height: 18px;
    color: var(--nova-purple);
}

.stats-card-header h3 {
    font-family: 'Outfit', -apple-system, sans-serif;
    font-size: 14px;
    font-weight: 600;
    color: var(--text-primary);
    margin: 0;
}

.stats-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 8px 0;
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
}

.stats-row:last-child {
    border-bottom: none;
    padding-bottom: 0;
}

.stats-label {
    display: flex;
    align-items: center;
    gap: 6px;
    font-size: 13px;
    color: var(--text-secondary);
}

.stats-label svg {
    width: 12px;
    height: 12px;
    color: var(--nova-gold);
    fill: var(--nova-gold);
}

.stats-value {
    font-family: 'Outfit', -apple-system, sans-serif;
    font-size: 16px;
    font-weight: 600;
    color: var(--text-primary);
}

.stats-value.gold {
    color: var(--nova-gold);
    text-shadow: 0 0 10px rgba(255, 215, 0, 0.5);
}

.stats-value.flame {
    color: var(--nova-orange);
    text-shadow: 0 0 10px rgba(255, 107, 53, 0.5);
}

.stats-value.time {
    font-family: 'DM Sans', -apple-system, sans-serif;
    color: var(--nova-cyan);
}

/* Leaderboard Tab */
.leaderboard-header {
    text-align: center;
    margin-bottom: 16px;
}

.leaderboard-header h2 {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    font-size: 18px;
    margin-bottom: 12px;
}

.leaderboard-header h2 svg {
    width: 20px;
    height: 20px;
    color: var(--nova-gold);
}

.leaderboard-filters {
    display: flex;
    justify-content: center;
    gap: 8px;
}

.lb-filter {
    padding: 6px 14px;
    background: var(--bg-surface);
    border: 1px solid var(--cell-border);
    border-radius: 20px;
    color: var(--text-secondary);
    font-size: 12px;
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.lb-filter:hover {
    border-color: var(--nova-purple);
    color: var(--text-primary);
}

.lb-filter.active {
    background: var(--nova-purple);
    border-color: var(--nova-purple);
    color: white;
}

.your-rank-card {
    background: linear-gradient(135deg, rgba(157, 78, 221, 0.2), rgba(76, 201, 240, 0.1));
    border: 1px solid var(--nova-purple);
    border-radius: 12px;
    padding: 12px 16px;
    margin-bottom: 12px;
}

.your-rank-label {
    font-size: 10px;
    font-weight: 600;
    color: var(--nova-purple);
    letter-spacing: 1px;
    margin-bottom: 6px;
}

.your-rank-info {
    display: flex;
    align-items: center;
    gap: 12px;
}

.your-rank-position {
    font-family: 'Outfit', sans-serif;
    font-size: 24px;
    font-weight: 700;
    color: var(--nova-gold);
    min-width: 50px;
}

.your-rank-name {
    flex: 1;
    font-size: 14px;
    font-weight: 500;
    color: var(--text-primary);
}

.your-rank-stat {
    font-size: 14px;
    font-weight: 600;
    color: var(--nova-cyan);
}

.leaderboard-list {
    max-height: 200px;
    overflow-y: auto;
    margin-bottom: 12px;
    border-radius: 8px;
    background: var(--bg-surface);
}

.leaderboard-loading,
.leaderboard-empty {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 40px 20px;
    color: var(--text-dim);
    font-size: 13px;
}

.leaderboard-loading svg,
.leaderboard-empty svg {
    width: 24px;
    height: 24px;
}

.leaderboard-loading svg.spin {
    animation: spin 1s linear infinite;
}

@keyframes spin {
    from { transform: rotate(0deg); }
    to { transform: rotate(360deg); }
}

.leaderboard-row {
    display: flex;
    align-items: center;
    padding: 10px 12px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
    transition: background var(--transition-fast);
}

.leaderboard-row:last-child {
    border-bottom: none;
}

.leaderboard-row:hover {
    background: rgba(255, 255, 255, 0.03);
}

.leaderboard-row.is-you {
    background: rgba(157, 78, 221, 0.15);
}

.leaderboard-row.gold .lb-rank {
    color: var(--nova-gold);
    text-shadow: 0 0 10px rgba(255, 215, 0, 0.5);
}

.leaderboard-row.silver .lb-rank {
    color: #C0C0C0;
    text-shadow: 0 0 10px rgba(192, 192, 192, 0.5);
}

.leaderboard-row.bronze .lb-rank {
    color: #CD7F32;
    text-shadow: 0 0 10px rgba(205, 127, 50, 0.5);
}

.lb-rank {
    font-family: 'Outfit', sans-serif;
    font-size: 14px;
    font-weight: 700;
    color: var(--text-dim);
    min-width: 30px;
}

.lb-name {
    flex: 1;
    font-size: 13px;
    color: var(--text-primary);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    margin-right: 12px;
}

.lb-stat {
    font-size: 12px;
    font-weight: 600;
    color: var(--nova-cyan);
}

.name-editor {
    background: var(--bg-surface);
    border: 1px solid var(--cell-border);
    border-radius: 10px;
    padding: 12px;
}

.name-editor label {
    display: block;
    font-size: 11px;
    color: var(--text-dim);
    margin-bottom: 8px;
}

.name-input-row {
    display: flex;
    gap: 8px;
}

.name-input-row input {
    flex: 1;
    padding: 8px 12px;
    background: var(--bg-deep);
    border: 1px solid var(--cell-border);
    border-radius: 8px;
    color: var(--text-primary);
    font-size: 14px;
    font-family: inherit;
}

.name-input-row input:focus {
    outline: none;
    border-color: var(--nova-purple);
}

.name-input-row button {
    padding: 8px 12px;
    background: var(--nova-purple);
    border: none;
    border-radius: 8px;
    color: white;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.name-input-row button:hover {
    background: var(--nova-pink);
}

.name-input-row button.saved {
    background: var(--nova-green);
}

.name-input-row button svg {
    width: 16px;
    height: 16px;
}

/* Difficulty Options */
.difficulty-options {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.diff-btn {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 4px;
    padding: 16px;
    background: var(--bg-surface);
    border: 1px solid var(--cell-border);
    border-radius: 12px;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.diff-btn:hover {
    border-color: var(--nova-purple);
    box-shadow: var(--glow-purple);
    transform: translateY(-2px);
}

.diff-btn:active {
    transform: scale(0.98);
}

.diff-stars {
    display: flex;
    gap: 4px;
    justify-content: center;
}

.diff-stars svg {
    width: 16px;
    height: 16px;
    color: var(--nova-gold);
    fill: var(--nova-gold);
    filter: drop-shadow(0 0 4px rgba(255, 215, 0, 0.5));
}

.diff-name {
    font-family: 'Outfit', -apple-system, sans-serif;
    font-size: 16px;
    font-weight: 700;
    color: var(--text-primary);
}

.diff-desc {
    font-size: 12px;
    color: var(--text-dim);
}

/* Victory Modal */
.modal-content.victory {
    background: linear-gradient(
        180deg,
        rgba(157, 78, 221, 0.2) 0%,
        var(--bg-mid) 30%
    );
}

.victory-stars {
    display: flex;
    justify-content: center;
    gap: 8px;
    margin-bottom: 16px;
    animation: stars-appear 0.6s ease;
}

.victory-stars svg {
    width: 40px;
    height: 40px;
    color: var(--nova-gold);
    fill: var(--nova-gold);
    filter: drop-shadow(0 0 12px rgba(255, 215, 0, 0.8));
}

/* Perfect Game Badge */
.perfect-badge {
    display: none;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 8px 20px;
    margin-bottom: 12px;
    background: linear-gradient(135deg, var(--nova-gold), var(--nova-orange));
    border-radius: 20px;
    font-family: 'Outfit', -apple-system, sans-serif;
    font-size: 14px;
    font-weight: 700;
    letter-spacing: 2px;
    color: var(--bg-deep);
    animation: perfect-pulse 1.5s ease-in-out infinite;
    box-shadow: 0 0 20px rgba(255, 215, 0, 0.6);
}

.perfect-badge.active {
    display: flex;
}

.perfect-badge svg {
    width: 18px;
    height: 18px;
}

@keyframes perfect-pulse {
    0%, 100% {
        transform: scale(1);
        box-shadow: 0 0 20px rgba(255, 215, 0, 0.6);
    }
    50% {
        transform: scale(1.05);
        box-shadow: 0 0 30px rgba(255, 215, 0, 0.9);
    }
}

.victory-stats {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 16px;
    margin: 24px 0;
}

.v-stat {
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.v-label {
    font-size: 11px;
    color: var(--text-dim);
    letter-spacing: 1px;
}

.v-value {
    font-family: 'Outfit', -apple-system, sans-serif;
    font-size: 20px;
    font-weight: 600;
    color: var(--nova-cyan);
}

.victory-buttons {
    display: flex;
    gap: 12px;
    margin-top: 24px;
}

.victory-btn {
    flex: 1;
    padding: 14px 20px;
    border-radius: 12px;
    font-family: 'Outfit', -apple-system, sans-serif;
    font-size: 12px;
    font-weight: 600;
    letter-spacing: 1px;
    cursor: pointer;
    transition: all var(--transition-fast);
    border: 1px solid var(--cell-border);
    background: var(--bg-surface);
    color: var(--text-secondary);
}

.victory-btn.primary {
    background: linear-gradient(135deg, var(--nova-pink), var(--nova-purple));
    border: none;
    color: white;
    box-shadow: var(--glow-pink);
}

.victory-btn:hover {
    transform: translateY(-2px);
}

.victory-btn:active {
    transform: scale(0.98);
}

/* Combo Popup */
.combo-popup {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%) scale(0);
    font-family: 'Outfit', -apple-system, sans-serif;
    font-size: 36px;
    font-weight: 800;
    color: var(--nova-gold);
    text-shadow: 
        0 0 20px rgba(255, 215, 0, 0.8),
        0 0 40px rgba(255, 215, 0, 0.5);
    z-index: 200;
    pointer-events: none;
    opacity: 0;
}

.combo-popup.active {
    animation: combo-pop 0.8s ease forwards;
}

/* Animations */
@keyframes pulse-glow {
    0%, 100% { 
        filter: drop-shadow(0 0 5px rgba(255, 45, 117, 0.5));
    }
    50% { 
        filter: drop-shadow(0 0 15px rgba(255, 45, 117, 0.8));
    }
}

@keyframes grid-glow-pulse {
    0%, 100% { opacity: 0.5; }
    50% { opacity: 1; }
}

@keyframes shake {
    0%, 100% { transform: translateX(0); }
    20%, 60% { transform: translateX(-4px); }
    40%, 80% { transform: translateX(4px); }
}

@keyframes blast-cell {
    0% { background: var(--cell-bg); }
    30% { background: rgba(255, 215, 0, 0.4); }
    100% { background: var(--cell-bg); }
}

@keyframes blast-wave {
    0% { transform: translate(-50%, -50%) scale(0); opacity: 1; }
    100% { transform: translate(-50%, -50%) scale(1.5); opacity: 0; }
}

@keyframes correct-bounce {
    0% { transform: scale(1); }
    30% { transform: scale(1.15); }
    60% { transform: scale(0.95); }
    100% { transform: scale(1); }
}

@keyframes combo-pop {
    0% { 
        transform: translate(-50%, -50%) scale(0);
        opacity: 0;
    }
    30% { 
        transform: translate(-50%, -50%) scale(1.3);
        opacity: 1;
    }
    70% { 
        transform: translate(-50%, -50%) scale(1);
        opacity: 1;
    }
    100% { 
        transform: translate(-50%, -60%) scale(0.8);
        opacity: 0;
    }
}

@keyframes stars-appear {
    0% { 
        transform: scale(0) rotate(-180deg);
        opacity: 0;
    }
    60% { 
        transform: scale(1.2) rotate(10deg);
    }
    100% { 
        transform: scale(1) rotate(0deg);
        opacity: 1;
    }
}

/* Row/Column/Box completion flash */
.cell.row-complete,
.cell.col-complete,
.cell.box-complete {
    animation: region-complete 0.6s ease;
}

@keyframes region-complete {
    0% { background: var(--cell-bg); }
    25% { background: rgba(0, 245, 212, 0.4); box-shadow: inset 0 0 20px rgba(0, 245, 212, 0.5); }
    50% { background: rgba(157, 78, 221, 0.3); }
    100% { background: var(--cell-bg); }
}

/* Level Up Animation */
.level-up-flash {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: radial-gradient(circle, rgba(255, 215, 0, 0.3) 0%, transparent 70%);
    z-index: 150;
    pointer-events: none;
    animation: level-flash 0.8s ease forwards;
}

@keyframes level-flash {
    0% { opacity: 0; }
    30% { opacity: 1; }
    100% { opacity: 0; }
}

/* Responsive Adjustments */
@media (max-height: 700px) {
    :root {
        --grid-size: min(85vw, 340px);
    }
    
    .stats-bar {
        padding: 8px 12px;
        margin-bottom: 8px;
    }
    
    .xp-bar-container {
        margin-bottom: 10px;
    }
    
    .powerups {
        margin-bottom: 10px;
    }
    
    .powerup {
        padding: 8px 12px;
    }
    
    .number-pad {
        margin-bottom: 8px;
    }
}

/* Smaller iPhones (iPhone 15/14/13 non-Pro Max, width ~393px) */
/* This does NOT apply to iPhone 15 Pro Max (430px width) */
@media (max-width: 414px) {
    .game-header {
        margin-bottom: 6px;
    }
    
    .stats-bar {
        padding: 8px 12px;
        margin-bottom: 6px;
    }
    
    .xp-bar-container {
        margin-bottom: 8px;
    }
    
    .powerups {
        margin-bottom: 8px;
        gap: 8px;
    }
    
    .powerup {
        padding: 8px 12px;
        gap: 2px;
    }
    
    .powerup-icon svg {
        width: 20px;
        height: 20px;
    }
    
    .powerup-name {
        font-size: 9px;
    }
    
    .number-pad {
        margin-bottom: 8px;
        padding: 2px 0;
    }
    
    .num-btn {
        font-size: 24px;
        padding: 8px 0;
        min-height: 44px;
    }
    
    .action-buttons {
        gap: 6px;
    }
    
    .action-btn {
        padding: 8px 6px;
        gap: 2px;
        font-size: 10px;
        border-radius: 10px;
    }
    
    .action-btn .action-icon svg {
        width: 16px;
        height: 16px;
    }
}

@media (max-width: 360px) {
    :root {
        --grid-size: min(92vw, 320px);
    }
    
    .logo-text {
        font-size: 16px;
    }
    
    .powerup-name {
        display: none;
    }
}

/* Touch feedback for iOS */
@supports (-webkit-touch-callout: none) {
    .num-btn:active,
    .action-btn:active,
    .powerup:active,
    .cell:active {
        opacity: 0.8;
    }
}

/* Hide scrollbars but allow scrolling if needed */
#app {
    scrollbar-width: none;
    -ms-overflow-style: none;
}

#app::-webkit-scrollbar {
    display: none;
}