/* CSS Custom Properties for Theming */
:root {
    /* Default Theme */
    --primary-color: #6366f1;
    --primary-dark: #4f46e5;
    --primary-light: #818cf8;
    --secondary-color: #f59e0b;
    --secondary-dark: #d97706;
    --secondary-light: #fbbf24;
    --accent-color: #ec4899;
    --accent-dark: #db2777;
    --accent-light: #f472b6;
    
    --background-primary: #ffffff;
    --background-secondary: #f8fafc;
    --background-tertiary: #e2e8f0;
    --background-overlay: rgba(0, 0, 0, 0.5);
    
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --text-tertiary: #94a3b8;
    --text-inverse: #ffffff;
    
    --border-color: #e2e8f0;
    --border-focus: #6366f1;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
    
    --gradient-primary: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
    --gradient-secondary: linear-gradient(135deg, var(--secondary-color), var(--secondary-dark));
    --gradient-accent: linear-gradient(135deg, var(--accent-color), var(--accent-dark));
    --gradient-background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    
    --border-radius-sm: 0.375rem;
    --border-radius-md: 0.5rem;
    --border-radius-lg: 0.75rem;
    --border-radius-xl: 1rem;
    --border-radius-full: 9999px;
    
    --transition-fast: 0.15s ease-out;
    --transition-normal: 0.3s ease-out;
    --transition-slow: 0.5s ease-out;
    
    --font-size-xs: 0.75rem;
    --font-size-sm: 0.875rem;
    --font-size-base: 1rem;
    --font-size-lg: 1.125rem;
    --font-size-xl: 1.25rem;
    --font-size-2xl: 1.5rem;
    --font-size-3xl: 1.875rem;
    --font-size-4xl: 2.25rem;
    
    --spacing-1: 0.25rem;
    --spacing-2: 0.5rem;
    --spacing-3: 0.75rem;
    --spacing-4: 1rem;
    --spacing-5: 1.25rem;
    --spacing-6: 1.5rem;
    --spacing-8: 2rem;
    --spacing-10: 2.5rem;
    --spacing-12: 3rem;
    --spacing-16: 4rem;
}

/* Dark Theme */
[data-theme="dark"] {
    --primary-color: #818cf8;
    --primary-dark: #6366f1;
    --primary-light: #a5b4fc;
    
    --background-primary: #0f172a;
    --background-secondary: #1e293b;
    --background-tertiary: #334155;
    --background-overlay: rgba(0, 0, 0, 0.7);
    
    --text-primary: #f1f5f9;
    --text-secondary: #cbd5e1;
    --text-tertiary: #94a3b8;
    
    --border-color: #334155;
    --gradient-background: linear-gradient(135deg, #1e3a8a 0%, #3730a3 100%);
}

/* Ocean Theme */
[data-theme="ocean"] {
    --primary-color: #0891b2;
    --primary-dark: #0e7490;
    --primary-light: #22d3ee;
    --secondary-color: #06b6d4;
    --accent-color: #8b5cf6;
    
    --background-primary: #f0f9ff;
    --background-secondary: #e0f2fe;
    --background-tertiary: #bae6fd;
    
    --gradient-background: linear-gradient(135deg, #0ea5e9 0%, #0284c7 100%);
}

/* Forest Theme */
[data-theme="forest"] {
    --primary-color: #059669;
    --primary-dark: #047857;
    --primary-light: #10b981;
    --secondary-color: #84cc16;
    --accent-color: #f59e0b;
    
    --background-primary: #f0fdf4;
    --background-secondary: #dcfce7;
    --background-tertiary: #bbf7d0;
    
    --gradient-background: linear-gradient(135deg, #059669 0%, #047857 100%);
}

/* Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    font-size: 16px;
    -webkit-text-size-adjust: 100%;
    -webkit-tap-highlight-color: transparent;
}

body {
    font-family: 'Poppins', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: var(--gradient-background);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
    min-height: 100vh;
    position: relative;
}

/* Screen Management */
.screen {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100vh;
    background: var(--background-primary);
    display: flex;
    flex-direction: column;
    opacity: 0;
    visibility: hidden;
    transform: translateY(20px);
    transition: all var(--transition-normal);
    z-index: 10;
    overflow-y: auto;
    -webkit-overflow-scrolling: touch;
}

.screen.active {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
    z-index: 20;
}

/* Loading Screen */
#loading-screen {
    background: var(--gradient-background);
    justify-content: center;
    align-items: center;
    text-align: center;
}

.loading-content {
    padding: var(--spacing-8);
}

.logo-container {
    margin-bottom: var(--spacing-8);
}

.logo-icon {
    font-size: var(--font-size-4xl);
    color: var(--text-inverse);
    margin-bottom: var(--spacing-4);
    display: block;
    animation: pulse 2s infinite;
}

.game-title {
    font-size: var(--font-size-3xl);
    font-weight: 700;
    color: var(--text-inverse);
    margin-bottom: var(--spacing-2);
    text-shadow: 0 2px 4px rgba(0, 0, 0, 0.3);
}

.game-subtitle {
    font-size: var(--font-size-lg);
    color: var(--text-inverse);
    opacity: 0.9;
    font-weight: 300;
}

.loading-spinner {
    width: 40px;
    height: 40px;
    border: 3px solid rgba(255, 255, 255, 0.3);
    border-top: 3px solid var(--text-inverse);
    border-radius: var(--border-radius-full);
    animation: spin 1s linear infinite;
    margin: var(--spacing-6) auto;
}

.loading-text {
    color: var(--text-inverse);
    font-size: var(--font-size-base);
    opacity: 0.8;
}

/* Main Menu */
#main-menu {
    background: var(--background-primary);
    padding: var(--spacing-6) var(--spacing-4);
}

.menu-header {
    text-align: center;
    margin-bottom: var(--spacing-8);
    padding-top: var(--spacing-8);
}

.menu-header .logo-icon {
    color: var(--primary-color);
    font-size: var(--font-size-4xl);
    margin-bottom: var(--spacing-4);
}

.menu-header .game-title {
    color: var(--text-primary);
    text-shadow: none;
    margin-bottom: var(--spacing-2);
}

.menu-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    max-width: 400px;
    margin: 0 auto;
    width: 100%;
}

.level-info {
    background: var(--background-secondary);
    border-radius: var(--border-radius-lg);
    padding: var(--spacing-6);
    margin-bottom: var(--spacing-8);
    box-shadow: var(--shadow-md);
}

.level-display {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--spacing-4);
}

.level-label {
    font-size: var(--font-size-lg);
    font-weight: 500;
    color: var(--text-secondary);
}

.level-number {
    font-size: var(--font-size-2xl);
    font-weight: 700;
    color: var(--primary-color);
}

.progress-bar {
    width: 100%;
    height: 8px;
    background: var(--background-tertiary);
    border-radius: var(--border-radius-full);
    overflow: hidden;
}

.progress-fill {
    height: 100%;
    background: var(--gradient-primary);
    border-radius: var(--border-radius-full);
    transition: width var(--transition-normal);
    width: 0%;
}

.menu-buttons {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-4);
}

.menu-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-3);
    padding: var(--spacing-4) var(--spacing-6);
    border: none;
    border-radius: var(--border-radius-lg);
    font-size: var(--font-size-lg);
    font-weight: 600;
    font-family: inherit;
    cursor: pointer;
    transition: all var(--transition-fast);
    position: relative;
    overflow: hidden;
    min-height: 60px;
}

.menu-btn.primary {
    background: var(--gradient-primary);
    color: var(--text-inverse);
    box-shadow: var(--shadow-lg);
    transform: translateY(0);
}

.menu-btn.primary:hover,
.menu-btn.primary:active {
    transform: translateY(-2px);
    box-shadow: var(--shadow-xl);
}

.menu-btn.secondary {
    background: var(--background-secondary);
    color: var(--text-primary);
    border: 2px solid var(--border-color);
    box-shadow: var(--shadow-sm);
}

.menu-btn.secondary:hover,
.menu-btn.secondary:active {
    background: var(--background-tertiary);
    border-color: var(--primary-color);
    transform: translateY(-1px);
}

.menu-btn i {
    font-size: var(--font-size-xl);
}

/* Game Screen */
#game-screen {
    background: var(--background-primary);
}

.game-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--spacing-4);
    background: var(--background-secondary);
    border-bottom: 1px solid var(--border-color);
    box-shadow: var(--shadow-sm);
}

.header-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 44px;
    height: 44px;
    border: none;
    border-radius: var(--border-radius-lg);
    background: var(--background-primary);
    color: var(--text-primary);
    font-size: var(--font-size-lg);
    cursor: pointer;
    transition: all var(--transition-fast);
    box-shadow: var(--shadow-sm);
    position: relative;
}

.header-btn:hover,
.header-btn:active {
    background: var(--primary-color);
    color: var(--text-inverse);
    transform: scale(1.05);
}

.hint-count {
    position: absolute;
    top: -8px;
    right: -8px;
    background: var(--accent-color);
    color: var(--text-inverse);
    font-size: var(--font-size-xs);
    font-weight: 700;
    width: 20px;
    height: 20px;
    border-radius: var(--border-radius-full);
    display: flex;
    align-items: center;
    justify-content: center;
}

.game-info {
    text-align: center;
}

.level-info-small {
    font-size: var(--font-size-sm);
    font-weight: 600;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-1);
}

.timer {
    font-size: var(--font-size-xl);
    font-weight: 700;
    color: var(--primary-color);
    font-family: 'Courier New', monospace;
}

.words-to-find {
    padding: var(--spacing-4);
    background: var(--background-secondary);
    margin: var(--spacing-4);
    border-radius: var(--border-radius-lg);
    box-shadow: var(--shadow-sm);
}

.words-to-find h3 {
    font-size: var(--font-size-lg);
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--spacing-3);
    text-align: center;
}

.words-list {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-2);
    justify-content: center;
}

.word-item {
    padding: var(--spacing-2) var(--spacing-3);
    background: var(--background-primary);
    border: 2px solid var(--border-color);
    border-radius: var(--border-radius-md);
    font-size: var(--font-size-sm);
    font-weight: 600;
    color: var(--text-primary);
    transition: all var(--transition-fast);
}

.word-item.found {
    background: var(--gradient-primary);
    color: var(--text-inverse);
    border-color: var(--primary-color);
    text-decoration: line-through;
    opacity: 0.8;
}

.game-board-container {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: var(--spacing-4);
}

.game-board {
    display: grid;
    gap: 2px;
    background: var(--border-color);
    border-radius: var(--border-radius-lg);
    padding: var(--spacing-2);
    box-shadow: var(--shadow-lg);
    max-width: 100%;
    aspect-ratio: 1;
    width: min(90vw, 400px);
}

.grid-cell {
    background: var(--background-primary);
    border-radius: var(--border-radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: var(--font-size-lg);
    font-weight: 700;
    color: var(--text-primary);
    cursor: pointer;
    transition: all var(--transition-fast);
    user-select: none;
    -webkit-user-select: none;
    -webkit-touch-callout: none;
    position: relative;
    aspect-ratio: 1;
    min-height: 30px;
}

.grid-cell:hover {
    background: var(--background-tertiary);
    transform: scale(1.05);
}

.grid-cell.selecting {
    background: var(--primary-light);
    color: var(--text-inverse);
    transform: scale(1.1);
    box-shadow: var(--shadow-md);
}

.grid-cell.found {
    background: var(--gradient-primary);
    color: var(--text-inverse);
    animation: foundPulse 0.6s ease-out;
}

.grid-cell.hint {
    background: var(--gradient-secondary);
    color: var(--text-inverse);
    animation: hintGlow 3s ease-in-out;
}

.grid-cell.shake {
    animation: shake 0.5s ease-in-out;
}

.game-controls {
    display: flex;
    gap: var(--spacing-4);
    padding: var(--spacing-4);
    justify-content: center;
}

.control-btn {
    display: flex;
    align-items: center;
    gap: var(--spacing-2);
    padding: var(--spacing-3) var(--spacing-4);
    border: none;
    border-radius: var(--border-radius-lg);
    background: var(--background-secondary);
    color: var(--text-primary);
    font-size: var(--font-size-sm);
    font-weight: 600;
    font-family: inherit;
    cursor: pointer;
    transition: all var(--transition-fast);
    box-shadow: var(--shadow-sm);
}

.control-btn:hover,
.control-btn:active {
    background: var(--primary-color);
    color: var(--text-inverse);
    transform: translateY(-1px);
}

/* Screen Headers */
.screen-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--spacing-4);
    background: var(--background-secondary);
    border-bottom: 1px solid var(--border-color);
    box-shadow: var(--shadow-sm);
}

.screen-header h2 {
    font-size: var(--font-size-xl);
    font-weight: 600;
    color: var(--text-primary);
}

.header-spacer {
    width: 44px;
}

/* Levels Screen */
.levels-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(80px, 1fr));
    gap: var(--spacing-3);
    padding: var(--spacing-4);
    max-width: 600px;
    margin: 0 auto;
}

.level-btn {
    aspect-ratio: 1;
    border: none;
    border-radius: var(--border-radius-lg);
    background: var(--background-secondary);
    color: var(--text-primary);
    font-size: var(--font-size-lg);
    font-weight: 700;
    font-family: inherit;
    cursor: pointer;
    transition: all var(--transition-fast);
    box-shadow: var(--shadow-sm);
    position: relative;
    overflow: hidden;
}

.level-btn:hover,
.level-btn:active {
    transform: scale(1.05);
    box-shadow: var(--shadow-md);
}

.level-btn.completed {
    background: var(--gradient-primary);
    color: var(--text-inverse);
}

.level-btn.current {
    background: var(--gradient-secondary);
    color: var(--text-inverse);
    animation: pulse 2s infinite;
}

.level-btn.locked {
    background: var(--background-tertiary);
    color: var(--text-tertiary);
    cursor: not-allowed;
    opacity: 0.5;
}

.level-btn.locked:hover {
    transform: none;
}

.level-btn::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    background: rgba(255, 255, 255, 0.3);
    border-radius: var(--border-radius-full);
    transform: translate(-50%, -50%);
    transition: all var(--transition-fast);
}

.level-btn:active::after {
    width: 100%;
    height: 100%;
}

/* Settings Screen */
.settings-content {
    padding: var(--spacing-4);
    max-width: 500px;
    margin: 0 auto;
}

.setting-group {
    margin-bottom: var(--spacing-8);
}

.setting-group h3 {
    font-size: var(--font-size-lg);
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--spacing-4);
    padding-bottom: var(--spacing-2);
    border-bottom: 2px solid var(--border-color);
}

.setting-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--spacing-4);
    background: var(--background-secondary);
    border-radius: var(--border-radius-lg);
    margin-bottom: var(--spacing-3);
    box-shadow: var(--shadow-sm);
}

.setting-item span {
    font-size: var(--font-size-base);
    font-weight: 500;
    color: var(--text-primary);
}

.toggle {
    position: relative;
    display: inline-block;
    width: 60px;
    height: 34px;
}

.toggle input {
    opacity: 0;
    width: 0;
    height: 0;
}

.slider {
    position: absolute;
    cursor: pointer;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: var(--background-tertiary);
    transition: var(--transition-normal);
    border-radius: 34px;
}

.slider:before {
    position: absolute;
    content: "";
    height: 26px;
    width: 26px;
    left: 4px;
    bottom: 4px;
    background-color: var(--text-inverse);
    transition: var(--transition-normal);
    border-radius: 50%;
    box-shadow: var(--shadow-sm);
}

input:checked + .slider {
    background: var(--gradient-primary);
}

input:checked + .slider:before {
    transform: translateX(26px);
}

.theme-selector {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--spacing-3);
}

.theme-btn {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-2);
    padding: var(--spacing-4);
    border: 2px solid var(--border-color);
    border-radius: var(--border-radius-lg);
    background: var(--background-secondary);
    color: var(--text-primary);
    font-size: var(--font-size-sm);
    font-weight: 600;
    font-family: inherit;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.theme-btn:hover,
.theme-btn.active {
    border-color: var(--primary-color);
    background: var(--background-primary);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.theme-preview {
    width: 40px;
    height: 40px;
    border-radius: var(--border-radius-md);
    position: relative;
    overflow: hidden;
}

.default-theme {
    background: linear-gradient(135deg, #6366f1, #8b5cf6);
}

.dark-theme {
    background: linear-gradient(135deg, #1e293b, #334155);
}

.ocean-theme {
    background: linear-gradient(135deg, #0891b2, #06b6d4);
}

.forest-theme {
    background: linear-gradient(135deg, #059669, #84cc16);
}

.setting-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-2);
    width: 100%;
    padding: var(--spacing-4);
    border: none;
    border-radius: var(--border-radius-lg);
    font-size: var(--font-size-base);
    font-weight: 600;
    font-family: inherit;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.setting-btn.danger {
    background: #ef4444;
    color: var(--text-inverse);
    box-shadow: var(--shadow-sm);
}

.setting-btn.danger:hover,
.setting-btn.danger:active {
    background: #dc2626;
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

/* Achievements Screen */
.achievements-content {
    padding: var(--spacing-4);
    max-width: 600px;
    margin: 0 auto;
}

.achievement-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-4);
    padding: var(--spacing-4);
    background: var(--background-secondary);
    border-radius: var(--border-radius-lg);
    margin-bottom: var(--spacing-3);
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-fast);
}

.achievement-item.unlocked {
    background: var(--gradient-primary);
    color: var(--text-inverse);
    box-shadow: var(--shadow-md);
}

.achievement-icon {
    width: 50px;
    height: 50px;
    border-radius: var(--border-radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: var(--font-size-xl);
    background: var(--background-primary);
    color: var(--primary-color);
    flex-shrink: 0;
}

.achievement-item.unlocked .achievement-icon {
    background: rgba(255, 255, 255, 0.2);
    color: var(--text-inverse);
}

.achievement-info {
    flex: 1;
}

.achievement-title {
    font-size: var(--font-size-lg);
    font-weight: 600;
    margin-bottom: var(--spacing-1);
}

.achievement-description {
    font-size: var(--font-size-sm);
    opacity: 0.8;
}

.achievement-progress {
    margin-top: var(--spacing-2);
}

.achievement-progress-bar {
    width: 100%;
    height: 6px;
    background: rgba(255, 255, 255, 0.2);
    border-radius: var(--border-radius-full);
    overflow: hidden;
}

.achievement-progress-fill {
    height: 100%;
    background: var(--text-inverse);
    border-radius: var(--border-radius-full);
    transition: width var(--transition-normal);
}

/* How to Play Screen */
.how-to-play-content {
    padding: var(--spacing-4);
    max-width: 500px;
    margin: 0 auto;
}

.instruction-card {
    display: flex;
    align-items: flex-start;
    gap: var(--spacing-4);
    padding: var(--spacing-6);
    background: var(--background-secondary);
    border-radius: var(--border-radius-lg);
    margin-bottom: var(--spacing-4);
    box-shadow: var(--shadow-sm);
}

.instruction-icon {
    width: 50px;
    height: 50px;
    border-radius: var(--border-radius-lg);
    background: var(--gradient-primary);
    color: var(--text-inverse);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: var(--font-size-xl);
    flex-shrink: 0;
}

.instruction-card h3 {
    font-size: var(--font-size-lg);
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--spacing-2);
}

.instruction-card p {
    font-size: var(--font-size-base);
    color: var(--text-secondary);
    line-height: 1.6;
}

/* Modals */
.modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100vh;
    background: var(--background-overlay);
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-normal);
    z-index: 1000;
    padding: var(--spacing-4);
}

.modal.active {
    opacity: 1;
    visibility: visible;
}

.modal-content {
    background: var(--background-primary);
    border-radius: var(--border-radius-xl);
    padding: var(--spacing-8);
    box-shadow: var(--shadow-xl);
    text-align: center;
    max-width: 400px;
    width: 100%;
    transform: scale(0.9);
    transition: transform var(--transition-normal);
}

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

.modal-content h3 {
    font-size: var(--font-size-2xl);
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: var(--spacing-6);
}

.modal-content p {
    font-size: var(--font-size-base);
    color: var(--text-secondary);
    margin-bottom: var(--spacing-6);
    line-height: 1.6;
}

.success-icon {
    font-size: var(--font-size-4xl);
    color: #10b981;
    margin-bottom: var(--spacing-4);
}

.level-stats {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-3);
    margin-bottom: var(--spacing-6);
    padding: var(--spacing-4);
    background: var(--background-secondary);
    border-radius: var(--border-radius-lg);
}

.stat {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.stat-label {
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
    font-weight: 500;
}

.stat-value {
    font-size: var(--font-size-base);
    color: var(--text-primary);
    font-weight: 700;
}

.modal-buttons {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-3);
}

.modal-btn {
    padding: var(--spacing-4) var(--spacing-6);
    border: none;
    border-radius: var(--border-radius-lg);
    font-size: var(--font-size-base);
    font-weight: 600;
    font-family: inherit;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.modal-btn.primary {
    background: var(--gradient-primary);
    color: var(--text-inverse);
    box-shadow: var(--shadow-md);
}

.modal-btn.primary:hover,
.modal-btn.primary:active {
    transform: translateY(-1px);
    box-shadow: var(--shadow-lg);
}

.modal-btn.secondary {
    background: var(--background-secondary);
    color: var(--text-primary);
    border: 2px solid var(--border-color);
}

.modal-btn.secondary:hover,
.modal-btn.secondary:active {
    background: var(--background-tertiary);
    border-color: var(--primary-color);
}

/* Toast Notifications */
#toast-container {
    position: fixed;
    top: var(--spacing-4);
    right: var(--spacing-4);
    z-index: 2000;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-2);
}

.toast {
    padding: var(--spacing-4) var(--spacing-6);
    border-radius: var(--border-radius-lg);
    color: var(--text-inverse);
    font-size: var(--font-size-sm);
    font-weight: 600;
    box-shadow: var(--shadow-lg);
    transform: translateX(100%);
    transition: transform var(--transition-normal);
    max-width: 300px;
}

.toast.show {
    transform: translateX(0);
}

.toast.success {
    background: #10b981;
}

.toast.error {
    background: #ef4444;
}

.toast.info {
    background: var(--primary-color);
}

.toast.warning {
    background: var(--secondary-color);
}

/* Particle Effects */
#particles-container {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100vh;
    pointer-events: none;
    z-index: 1500;
}

.particle {
    position: absolute;
    width: 6px;
    height: 6px;
    background: var(--primary-color);
    border-radius: var(--border-radius-full);
    animation: particleFloat 2s ease-out forwards;
}

/* Animations */
@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.7; }
}

@keyframes foundPulse {
    0% { transform: scale(1); }
    50% { transform: scale(1.2); }
    100% { transform: scale(1); }
}

@keyframes hintGlow {
    0%, 100% { box-shadow: 0 0 0 rgba(251, 191, 36, 0.5); }
    50% { box-shadow: 0 0 20px rgba(251, 191, 36, 0.8); }
}

@keyframes shake {
    0%, 100% { transform: translateX(0); }
    25% { transform: translateX(-5px); }
    75% { transform: translateX(5px); }
}

@keyframes particleFloat {
    0% {
        opacity: 1;
        transform: translateY(0) scale(1);
    }
    100% {
        opacity: 0;
        transform: translateY(-100px) scale(0);
    }
}

@keyframes slideInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes slideInDown {
    from {
        opacity: 0;
        transform: translateY(-30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

@keyframes bounceIn {
    0% {
        opacity: 0;
        transform: scale(0.3);
    }
    50% {
        opacity: 1;
        transform: scale(1.05);
    }
    70% {
        transform: scale(0.9);
    }
    100% {
        opacity: 1;
        transform: scale(1);
    }
}

/* Responsive Design */
@media (max-width: 480px) {
    .game-board {
        width: min(95vw, 350px);
    }
    
    .grid-cell {
        font-size: var(--font-size-base);
        min-height: 25px;
    }
    
    .menu-btn {
        min-height: 50px;
        font-size: var(--font-size-base);
    }
    
    .words-list {
        gap: var(--spacing-1);
    }
    
    .word-item {
        padding: var(--spacing-1) var(--spacing-2);
        font-size: var(--font-size-xs);
    }
    
    .levels-grid {
        grid-template-columns: repeat(auto-fill, minmax(60px, 1fr));
        gap: var(--spacing-2);
    }
    
    .theme-selector {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 360px) {
    .game-board {
        width: min(98vw, 320px);
    }
    
    .grid-cell {
        font-size: var(--font-size-sm);
        min-height: 22px;
    }
    
    .game-header {
        padding: var(--spacing-2);
    }
    
    .header-btn {
        width: 40px;
        height: 40px;
        font-size: var(--font-size-base);
    }
}

/* Landscape orientation adjustments */
@media (orientation: landscape) and (max-height: 500px) {
    .screen {
        padding-top: var(--spacing-2);
    }
    
    .menu-header {
        padding-top: var(--spacing-4);
        margin-bottom: var(--spacing-4);
    }
    
    .game-board {
        width: min(60vh, 350px);
    }
    
    .words-to-find {
        margin: var(--spacing-2);
        padding: var(--spacing-2);
    }
    
    .game-controls {
        padding: var(--spacing-2);
    }
}

/* High DPI displays */
@media (-webkit-min-device-pixel-ratio: 2), (min-resolution: 192dpi) {
    .grid-cell {
        border: 0.5px solid var(--border-color);
    }
}

/* Accessibility */
@media (prefers-reduced-motion: reduce) {
    * {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}

/* Focus styles for accessibility */
button:focus,
.grid-cell:focus {
    outline: 2px solid var(--primary-color);
    outline-offset: 2px;
}

/* Print styles */
@media print {
    .screen {
        position: static;
        height: auto;
        opacity: 1;
        visibility: visible;
        transform: none;
    }
    
    .game-board {
        box-shadow: none;
        border: 2px solid #000;
    }
    
    .grid-cell {
        border: 1px solid #000;
        color: #000 !important;
        background: #fff !important;
    }
}