:root {
    --primary: #FF006E;
    --secondary: #FB5607;
    --accent: #FFBE0B;
    --purple: #8338EC;
    --blue: #3A86FF;
    --dark: #1a1a1a;
    --light: #ffffff;
    --gray: #666666;
    --success: #10b981;
    --danger: #ef4444;
    --warning: #f59e0b;
    
    --gradient-primary: linear-gradient(135deg, var(--primary), var(--purple));
    --gradient-secondary: linear-gradient(135deg, var(--secondary), var(--accent));
    --gradient-blue: linear-gradient(135deg, var(--blue), var(--purple));
    --gradient-holographic: linear-gradient(45deg, var(--primary), var(--secondary), var(--accent), var(--purple), var(--blue));
    
    --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 4px 8px rgba(0, 0, 0, 0.15);
    --shadow-lg: 0 8px 16px rgba(0, 0, 0, 0.2);
    --shadow-glow: 0 0 20px rgba(255, 0, 110, 0.3);
    
    --border-radius: 12px;
    --border-radius-lg: 16px;
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: var(--dark);
    color: var(--light);
    overflow-x: hidden;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: var(--gradient-holographic);
    opacity: 0.05;
    z-index: -1;
    animation: holographicShift 10s ease-in-out infinite;
}

@keyframes holographicShift {
    0%, 100% { transform: translateX(0) rotate(0deg); }
    25% { transform: translateX(-2px) rotate(0.5deg); }
    50% { transform: translateX(2px) rotate(-0.5deg); }
    75% { transform: translateX(-1px) rotate(0.25deg); }
}

.app-header {
    background: var(--gradient-primary);
    padding: 1rem;
    box-shadow: var(--shadow-lg);
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-content {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.header-content h1 {
    font-size: 1.5rem;
    font-weight: 700;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.3);
}

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

.stat {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    background: rgba(255, 255, 255, 0.2);
    padding: 0.5rem 1rem;
    border-radius: var(--border-radius);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.stat i {
    color: var(--accent);
}

.app-main {
    flex: 1;
    padding: 1rem;
    padding-bottom: 5rem;
    max-width: 1200px;
    margin: 0 auto;
    width: 100%;
}

.screen {
    display: none;
    animation: fadeIn 0.3s ease-in-out;
}

.screen.active {
    display: block;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

.screen-header {
    text-align: center;
    margin-bottom: 2rem;
}

.screen-header h2 {
    font-size: 2rem;
    background: var(--gradient-primary);
    background-clip: text;
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    margin-bottom: 0.5rem;
}

.game-container {
    position: relative;
    background: var(--gradient-blue);
    border-radius: var(--border-radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow-lg);
    margin-bottom: 1rem;
}

#gameCanvas {
    display: block;
    width: 100%;
    height: auto;
    max-height: 60vh;
    background: linear-gradient(to bottom, #87CEEB 0%, #87CEEB 30%, #90EE90 30%, #90EE90 70%, #8B4513 70%, #8B4513 100%);
}

.game-overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
}

.game-ui {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    pointer-events: none;
}

.ui-top {
    position: absolute;
    top: 1rem;
    left: 1rem;
    right: 1rem;
    display: flex;
    justify-content: space-between;
    gap: 1rem;
}

.score-display, .distance-display {
    background: rgba(0, 0, 0, 0.7);
    padding: 0.5rem 1rem;
    border-radius: var(--border-radius);
    display: flex;
    align-items: center;
    gap: 0.5rem;
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.2);
}

.score-display i {
    color: var(--accent);
}

.distance-display i {
    color: var(--blue);
}

.ui-bottom {
    position: absolute;
    bottom: 1rem;
    left: 50%;
    transform: translateX(-50%);
}

.wheelie-indicator {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.5rem;
}

.wheelie-bar {
    width: 200px;
    height: 8px;
    background: rgba(0, 0, 0, 0.5);
    border-radius: 4px;
    overflow: hidden;
    border: 1px solid rgba(255, 255, 255, 0.2);
}

.wheelie-fill {
    height: 100%;
    background: var(--gradient-secondary);
    width: 0%;
    transition: width 0.1s ease-out;
}

.wheelie-indicator span {
    color: var(--accent);
    font-weight: bold;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.5);
}

.start-screen, .game-over-screen {
    background: rgba(0, 0, 0, 0.9);
    padding: 2rem;
    border-radius: var(--border-radius-lg);
    text-align: center;
    backdrop-filter: blur(20px);
    border: 1px solid rgba(255, 255, 255, 0.1);
    max-width: 400px;
    margin: 0 auto;
}

.start-screen h2, .game-over-screen h2 {
    font-size: 2rem;
    margin-bottom: 1rem;
    background: var(--gradient-primary);
    background-clip: text;
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.controls-info {
    margin-top: 1.5rem;
    padding: 1rem;
    background: rgba(255, 255, 255, 0.1);
    border-radius: var(--border-radius);
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.controls-info p {
    margin: 0.5rem 0;
    font-size: 0.9rem;
}

.final-stats {
    margin: 1.5rem 0;
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.final-stats .stat {
    background: rgba(255, 255, 255, 0.1);
    justify-content: center;
}

.game-over-buttons {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
}

.game-btn {
    background: var(--gradient-primary);
    border: none;
    padding: 0.75rem 1.5rem;
    border-radius: var(--border-radius);
    color: var(--light);
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    display: flex;
    align-items: center;
    gap: 0.5rem;
    box-shadow: var(--shadow-md);
    min-width: 120px;
    justify-content: center;
}

.game-btn:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.game-btn:active {
    transform: translateY(0);
}

.game-btn.secondary {
    background: var(--gradient-blue);
}

.game-btn.danger {
    background: linear-gradient(135deg, var(--danger), #dc2626);
}

.game-btn.primary {
    background: var(--gradient-primary);
}

.game-controls {
    display: flex;
    justify-content: center;
    padding: 1rem;
}

.wheelie-control {
    background: var(--gradient-secondary);
    border: none;
    padding: 1rem 2rem;
    border-radius: var(--border-radius-lg);
    color: var(--light);
    font-weight: 700;
    font-size: 1.1rem;
    cursor: pointer;
    transition: var(--transition);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.5rem;
    box-shadow: var(--shadow-lg);
    user-select: none;
    min-width: 120px;
    min-height: 80px;
}

.wheelie-control:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-glow);
}

.wheelie-control:active,
.wheelie-control.active {
    transform: translateY(0);
    background: var(--gradient-primary);
    box-shadow: var(--shadow-glow);
}

.wheelie-control i {
    font-size: 1.5rem;
}

.leaderboard-container {
    max-width: 600px;
    margin: 0 auto;
}

.leaderboard-list {
    background: rgba(255, 255, 255, 0.05);
    border-radius: var(--border-radius-lg);
    padding: 1rem;
    margin-bottom: 1rem;
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.leaderboard-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem;
    background: rgba(255, 255, 255, 0.1);
    border-radius: var(--border-radius);
    margin-bottom: 0.5rem;
    border: 1px solid rgba(255, 255, 255, 0.1);
    transition: var(--transition);
}

.leaderboard-item:hover {
    background: rgba(255, 255, 255, 0.15);
    transform: translateX(5px);
}

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

.leaderboard-rank {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-weight: 700;
    min-width: 60px;
}

.leaderboard-rank.gold { color: var(--accent); }
.leaderboard-rank.silver { color: #c0c0c0; }
.leaderboard-rank.bronze { color: #cd7f32; }

.leaderboard-info {
    flex: 1;
    margin: 0 1rem;
}

.leaderboard-score {
    font-weight: 700;
    color: var(--primary);
}

.leaderboard-details {
    font-size: 0.8rem;
    color: var(--gray);
    margin-top: 0.25rem;
}

.empty-state {
    text-align: center;
    padding: 2rem;
    color: var(--gray);
}

.empty-state i {
    font-size: 3rem;
    margin-bottom: 1rem;
    color: var(--primary);
}

.settings-container {
    max-width: 600px;
    margin: 0 auto;
}

.setting-group {
    background: rgba(255, 255, 255, 0.05);
    border-radius: var(--border-radius-lg);
    padding: 1.5rem;
    margin-bottom: 1rem;
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.setting-group h3 {
    margin-bottom: 1rem;
    color: var(--primary);
    font-size: 1.2rem;
}

.setting-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 0;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.setting-item:last-child {
    border-bottom: none;
    padding-bottom: 0;
}

.setting-item label {
    font-weight: 500;
}

.toggle-switch {
    position: relative;
    width: 50px;
    height: 24px;
}

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

.slider {
    position: absolute;
    cursor: pointer;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: var(--gray);
    transition: var(--transition);
    border-radius: 24px;
}

.slider:before {
    position: absolute;
    content: "";
    height: 18px;
    width: 18px;
    left: 3px;
    bottom: 3px;
    background: var(--light);
    transition: var(--transition);
    border-radius: 50%;
}

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

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

.volume-slider {
    width: 100px;
    margin-right: 0.5rem;
}

.setting-select {
    background: rgba(255, 255, 255, 0.1);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: var(--border-radius);
    padding: 0.5rem;
    color: var(--light);
    font-size: 0.9rem;
}

.setting-select option {
    background: var(--dark);
    color: var(--light);
}

.faq-container {
    max-width: 800px;
    margin: 0 auto;
}

.faq-item {
    background: rgba(255, 255, 255, 0.05);
    border-radius: var(--border-radius);
    margin-bottom: 0.5rem;
    overflow: hidden;
    border: 1px solid rgba(255, 255, 255, 0.1);
    transition: var(--transition);
}

.faq-item:hover {
    background: rgba(255, 255, 255, 0.08);
}

.faq-question {
    width: 100%;
    background: none;
    border: none;
    padding: 1rem 1.5rem;
    color: var(--light);
    font-size: 1rem;
    font-weight: 500;
    text-align: left;
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    transition: var(--transition);
}

.faq-question:hover {
    color: var(--primary);
}

.faq-icon {
    font-size: 1.2rem;
    font-weight: 700;
    color: var(--primary);
    transition: var(--transition);
}

.faq-question[aria-expanded="true"] .faq-icon {
    transform: rotate(45deg);
}

.faq-answer {
    padding: 0 1.5rem 1rem;
    color: var(--gray);
    line-height: 1.6;
    animation: slideDown 0.3s ease-out;
}

.faq-answer[hidden] {
    display: none;
}

@keyframes slideDown {
    from {
        opacity: 0;
        transform: translateY(-10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.bottom-nav {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    background: rgba(26, 26, 26, 0.95);
    backdrop-filter: blur(20px);
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    display: flex;
    justify-content: space-around;
    padding: 0.5rem 0;
    z-index: 1000;
}

.nav-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.25rem;
    color: var(--gray);
    text-decoration: none;
    padding: 0.5rem;
    border-radius: var(--border-radius);
    transition: var(--transition);
    min-width: 60px;
}

.nav-item:hover {
    color: var(--primary);
    background: rgba(255, 0, 110, 0.1);
}

.nav-item.active {
    color: var(--primary);
    background: rgba(255, 0, 110, 0.2);
}

.nav-item i {
    font-size: 1.2rem;
}

.nav-item span {
    font-size: 0.7rem;
    font-weight: 500;
}

footer {
    background: var(--dark);
    padding: 1rem;
    text-align: center;
    color: var(--gray);
    font-size: 0.8rem;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    margin-bottom: 4rem;
}

.hidden {
    display: none !important;
}

@media (max-width: 768px) {
    .app-main {
        padding: 0.5rem;
        padding-bottom: 5rem;
    }
    
    .header-content h1 {
        font-size: 1.2rem;
    }
    
    .header-stats {
        gap: 0.5rem;
    }
    
    .stat {
        padding: 0.3rem 0.6rem;
        font-size: 0.8rem;
    }
    
    .start-screen, .game-over-screen {
        padding: 1.5rem;
        margin: 1rem;
    }
    
    .game-over-buttons {
        flex-direction: column;
        align-items: center;
    }
    
    .game-btn {
        min-width: 200px;
    }
    
    .ui-top {
        flex-direction: column;
        gap: 0.5rem;
    }
    
    .wheelie-bar {
        width: 150px;
    }
    
    .wheelie-control {
        min-width: 100px;
        min-height: 70px;
        font-size: 1rem;
        padding: 0.8rem 1.5rem;
    }
    
    .leaderboard-item {
        flex-direction: column;
        text-align: center;
        gap: 0.5rem;
    }
    
    .leaderboard-rank {
        min-width: auto;
    }
    
    .setting-item {
        flex-direction: column;
        align-items: flex-start;
        gap: 0.5rem;
    }
    
    .setting-item > * {
        width: 100%;
    }
    
    .toggle-switch {
        width: 50px;
        align-self: flex-end;
    }
    
    .volume-slider {
        width: 100%;
        margin-right: 0;
    }
}

@media (max-width: 480px) {
    .header-content {
        flex-direction: column;
        gap: 0.5rem;
    }
    
    .screen-header h2 {
        font-size: 1.5rem;
    }
    
    .nav-item span {
        font-size: 0.6rem;
    }
    
    .nav-item i {
        font-size: 1rem;
    }
}

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