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

:root {
    --primary-color: #3b82f6;
    --secondary-color: #10b981;
    --accent-color: #f59e0b;
    --danger-color: #ef4444;
    --bg-primary: #0f172a;
    --bg-secondary: #1e293b;
    --bg-tertiary: #334155;
    --text-primary: #f1f5f9;
    --text-secondary: #cbd5e1;
    --border-color: #475569;
    
    --color-red: #ef4444;
    --color-blue: #3b82f6;
    --color-green: #10b981;
    --color-yellow: #fbbf24;
    --color-purple: #a855f7;
    --color-pink: #ec4899;
    --color-cyan: #06b6d4;
    --color-orange: #f97316;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background: linear-gradient(135deg, var(--bg-primary) 0%, #1a1f35 100%);
    color: var(--text-primary);
    min-height: 100vh;
    overflow: hidden;
}

.app {
    width: 100%;
    height: 100vh;
    display: flex;
    position: relative;
}

/* Screens */
.screen {
    position: absolute;
    width: 100%;
    height: 100%;
    display: flex;
    flex-direction: column;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.3s ease, visibility 0.3s ease;
    z-index: 1;
    overflow-y: auto;
}

.screen.active {
    opacity: 1;
    visibility: visible;
    z-index: 10;
}

/* Main Menu */
.menu-container {
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    height: 100%;
    padding: 2rem;
    text-align: center;
}

.app-title {
    font-size: 3.5rem;
    margin-bottom: 0.5rem;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.subtitle {
    font-size: 1.2rem;
    color: var(--text-secondary);
    margin-bottom: 3rem;
}

.menu-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1.5rem;
    margin-bottom: 3rem;
    width: 100%;
    max-width: 800px;
}

.menu-btn {
    padding: 1.5rem;
    border: 2px solid var(--border-color);
    background: var(--bg-secondary);
    color: var(--text-primary);
    border-radius: 12px;
    font-size: 1rem;
    cursor: pointer;
    transition: all 0.3s ease;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.5rem;
}

.menu-btn:hover {
    border-color: var(--primary-color);
    background: var(--bg-tertiary);
    transform: translateY(-4px);
    box-shadow: 0 8px 24px rgba(59, 130, 246, 0.2);
}

.game-btn .icon {
    font-size: 2.5rem;
}

.game-btn .name {
    font-weight: 600;
    font-size: 1.1rem;
}

.game-btn .desc {
    font-size: 0.85rem;
    color: var(--text-secondary);
}

.secondary-btn {
    margin: 0 0.5rem;
}

.menu-footer {
    display: flex;
    gap: 1rem;
    justify-content: center;
}

/* Game Header */
.game-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1.5rem 2rem;
    background: var(--bg-secondary);
    border-bottom: 2px solid var(--border-color);
}

.back-btn {
    padding: 0.75rem 1.5rem;
    border: none;
    background: var(--bg-tertiary);
    color: var(--text-primary);
    border-radius: 8px;
    cursor: pointer;
    font-size: 1rem;
    transition: all 0.3s ease;
}

.back-btn:hover {
    background: var(--primary-color);
    transform: translateX(-2px);
}

.game-header h2 {
    flex: 1;
    text-align: center;
    margin: 0 1rem;
}

.header-stats {
    display: flex;
    gap: 2rem;
    font-size: 1rem;
}

.header-stats span {
    color: var(--text-secondary);
}

.header-stats strong {
    color: var(--primary-color);
    font-size: 1.2rem;
}

/* Game Container */
.game-container {
    flex: 1;
    display: flex;
    padding: 2rem;
    gap: 1.5rem;
    overflow: hidden;
}

.game-canvas {
    flex: 1;
    background: var(--bg-tertiary);
    border: 2px solid var(--border-color);
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    overflow: hidden;
}

#ropeCanvas {
    cursor: crosshair;
}

#colorSortCanvas {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 1rem;
    padding: 2rem;
    align-content: center;
    justify-content: center;
}

#paintNumbersCanvas {
    display: flex;
    align-items: center;
    justify-content: center;
}

#paintSvg {
    width: 100%;
    height: 100%;
    max-width: 600px;
    max-height: 600px;
}

/* Game Controls */
.game-controls,
.paint-sidebar {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    width: 150px;
}

.control-btn {
    padding: 1rem;
    border: 2px solid var(--border-color);
    background: var(--bg-secondary);
    color: var(--text-primary);
    border-radius: 8px;
    font-size: 0.95rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s ease;
}

.control-btn:hover:not(:disabled) {
    border-color: var(--primary-color);
    background: var(--primary-color);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(59, 130, 246, 0.2);
}

.control-btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.control-btn.secondary-btn {
    background: var(--bg-tertiary);
}

.control-btn.danger-btn {
    border-color: var(--danger-color);
    color: var(--danger-color);
}

.control-btn.danger-btn:hover {
    background: var(--danger-color);
    color: white;
}

/* Color Palette */
.color-palette {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 0.5rem;
}

.color-btn {
    width: 100%;
    height: 50px;
    border: 3px solid transparent;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.3s ease;
}

.color-btn:hover {
    transform: scale(1.05);
}

.color-btn.selected {
    border-color: var(--text-primary);
    box-shadow: 0 0 12px currentColor;
}

/* Tubes (Color Sort) */
.tube {
    width: 60px;
    height: 140px;
    border: 2px solid var(--border-color);
    border-radius: 8px;
    background: var(--bg-primary);
    cursor: pointer;
    transition: all 0.3s ease;
    display: flex;
    flex-direction: column-reverse;
    padding: 4px;
    gap: 2px;
}

.tube:hover {
    border-color: var(--primary-color);
    box-shadow: 0 0 12px rgba(59, 130, 246, 0.2);
}

.tube.selected {
    border-color: var(--primary-color);
    box-shadow: 0 0 16px rgba(59, 130, 246, 0.4);
}

.ball {
    width: 100%;
    height: 25px;
    border-radius: 4px;
    cursor: pointer;
    transition: all 0.2s ease;
}

/* Statistics Screen */
.stats-container {
    padding: 2rem;
    overflow-y: auto;
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1.5rem;
    margin-bottom: 3rem;
}

.stat-card {
    background: linear-gradient(135deg, var(--bg-secondary), var(--bg-tertiary));
    padding: 1.5rem;
    border-radius: 12px;
    border: 2px solid var(--border-color);
    text-align: center;
}

.stat-card h3 {
    font-size: 1.1rem;
    margin-bottom: 1rem;
    color: var(--text-secondary);
}

.stat-value {
    font-size: 2.5rem;
    font-weight: bold;
    color: var(--primary-color);
}

.achievements-section {
    margin-bottom: 2rem;
}

.achievements-section h3 {
    margin-bottom: 1rem;
    font-size: 1.3rem;
}

.achievements-list {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
    gap: 1rem;
}

.achievement-item {
    background: var(--bg-secondary);
    padding: 1rem;
    border-radius: 8px;
    text-align: center;
    border: 2px solid var(--border-color);
    transition: all 0.3s ease;
}

.achievement-item.unlocked {
    border-color: var(--accent-color);
    background: linear-gradient(135deg, var(--bg-secondary), rgba(245, 158, 11, 0.1));
}

.achievement-icon {
    font-size: 2rem;
    margin-bottom: 0.5rem;
}

.achievement-name {
    font-weight: 600;
    font-size: 0.9rem;
    margin-bottom: 0.25rem;
}

.achievement-desc {
    font-size: 0.8rem;
    color: var(--text-secondary);
}

.game-stats {
    background: var(--bg-secondary);
    padding: 1.5rem;
    border-radius: 12px;
    margin-bottom: 2rem;
}

.game-stat-row {
    display: flex;
    justify-content: space-between;
    padding: 0.75rem 0;
    border-bottom: 1px solid var(--border-color);
}

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

.game-stat-name {
    color: var(--text-secondary);
}

.game-stat-value {
    color: var(--primary-color);
    font-weight: 600;
}

/* Help Screen */
.help-container {
    padding: 2rem;
    overflow-y: auto;
    max-width: 900px;
    margin: 0 auto;
}

.help-section {
    background: var(--bg-secondary);
    padding: 1.5rem;
    margin-bottom: 1.5rem;
    border-radius: 12px;
    border-left: 4px solid var(--primary-color);
}

.help-section h3 {
    font-size: 1.3rem;
    margin-bottom: 1rem;
    color: var(--primary-color);
}

.help-section p {
    color: var(--text-secondary);
    margin-bottom: 1rem;
    line-height: 1.6;
}

.help-section ul {
    list-style: none;
    padding-left: 1rem;
}

.help-section li {
    color: var(--text-secondary);
    margin-bottom: 0.75rem;
    padding-left: 1.5rem;
    position: relative;
}

.help-section li:before {
    content: "→";
    position: absolute;
    left: 0;
    color: var(--primary-color);
}

.help-section.tips {
    border-left-color: var(--secondary-color);
    background: linear-gradient(135deg, var(--bg-secondary), rgba(16, 185, 129, 0.1));
}

.help-section.tips h3 {
    color: var(--secondary-color);
}

/* Victory Modal */
.modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.7);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 100;
}

.modal-content {
    background: linear-gradient(135deg, var(--bg-secondary), var(--bg-tertiary));
    padding: 2rem;
    border-radius: 16px;
    border: 2px solid var(--border-color);
    text-align: center;
    max-width: 500px;
    animation: slideUp 0.3s ease;
}

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

.modal-content h2 {
    font-size: 2rem;
    margin-bottom: 1rem;
    color: var(--accent-color);
}

.modal-content p {
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
    line-height: 1.6;
}

.modal-stats {
    background: var(--bg-primary);
    padding: 1rem;
    border-radius: 8px;
    margin-bottom: 1.5rem;
}

.modal-stat {
    padding: 0.5rem 0;
    font-size: 1rem;
    color: var(--text-secondary);
}

.modal-stat strong {
    color: var(--primary-color);
}

.modal-content .control-btn {
    width: 100%;
    margin-bottom: 0.5rem;
}

/* Responsive */
@media (max-width: 768px) {
    .game-header {
        flex-wrap: wrap;
        gap: 1rem;
    }

    .game-header h2 {
        flex-basis: 100%;
        order: 1;
    }

    .game-header .back-btn {
        order: 2;
    }

    .header-stats {
        flex-basis: 100%;
        order: 3;
        justify-content: center;
    }

    .game-container {
        flex-direction: column;
        padding: 1rem;
    }

    .game-controls,
    .paint-sidebar {
        flex-direction: row;
        width: 100%;
        height: auto;
    }

    .control-btn {
        flex: 1;
    }

    .menu-grid {
        grid-template-columns: 1fr;
    }

    .app-title {
        font-size: 2rem;
    }

    #colorSortCanvas {
        grid-template-columns: repeat(3, 1fr);
    }
}

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

@keyframes glow {
    0%, 100% {
        box-shadow: 0 0 8px rgba(59, 130, 246, 0.2);
    }
    50% {
        box-shadow: 0 0 16px rgba(59, 130, 246, 0.4);
    }
}

.tube.selected {
    animation: glow 1.5s ease-in-out infinite;
}

/* Scrollbar */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: var(--bg-secondary);
}

::-webkit-scrollbar-thumb {
    background: var(--border-color);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--primary-color);
}

/* Print Styles */
@media print {
    body {
        background: white;
    }

    .screen {
        position: static;
    }
}