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

.hidden {
    display: none !important;
}

:root {
    --accent-color: #42ec9d;
    --bg-dark: #0a0a0a;
    --glass-bg: rgba(10, 10, 10, 0.8);
    --glass-border: rgba(255, 255, 255, 0.1);
    --text-primary: #ffffff;
    --text-secondary: rgba(255, 255, 255, 0.7);
}

body {
    background: var(--bg-dark);
    color: var(--text-primary);
    font-family: 'Poppins', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    overflow: hidden;
    width: 100vw;
    height: 100vh;
}

/* Canvas */
#glCanvas {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    display: block;
}

/* Info Toggle Button */
.info-toggle {
    position: fixed;
    top: 20px;
    right: 20px;
    width: 44px;
    height: 44px;
    border-radius: 50%;
    border: 1px solid var(--glass-border);
    background: var(--glass-bg);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    color: var(--text-primary);
    font-size: 20px;
    font-weight: bold;
    cursor: pointer;
    transition: all 0.3s ease;
    z-index: 100;
}

.info-toggle:hover {
    background: rgba(0, 255, 136, 0.2);
    border-color: var(--accent-color);
    color: var(--accent-color);
}

/* Pause/Play Toggle Button */
.pause-toggle {
    position: fixed;
    top: 74px;
    right: 20px;
    width: 44px;
    height: 44px;
    border-radius: 50%;
    border: 1px solid var(--glass-border);
    background: var(--glass-bg);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    color: var(--text-primary);
    font-size: 20px;
    cursor: pointer;
    transition: all 0.3s ease;
    z-index: 100;
    display: flex;
    align-items: center;
    justify-content: center;
}

.pause-toggle:hover {
    background: rgba(0, 255, 136, 0.2);
    border-color: var(--accent-color);
    color: var(--accent-color);
}

.pause-icon,
.play-icon {
    transition: opacity 0.2s ease;
}

.play-icon {
    padding-left: 2px;
}

/* Info Panel */
.info-panel {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.9);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 200;
    opacity: 1;
    transition: opacity 0.3s ease;
}

.info-panel.hidden {
    opacity: 0;
    pointer-events: none;
}

.info-content {
    max-width: 600px;
    padding: 40px;
    background: var(--glass-bg);
    border: 1px solid var(--glass-border);
    border-radius: 16px;
    position: relative;
    max-height: 80vh;
    overflow-y: auto;
}

.info-close {
    position: absolute;
    top: 15px;
    right: 15px;
    width: 32px;
    height: 32px;
    border: none;
    background: transparent;
    color: var(--text-secondary);
    font-size: 28px;
    cursor: pointer;
    transition: color 0.2s ease;
    line-height: 1;
}

.info-close:hover {
    color: var(--accent-color);
}

.info-content h2 {
    font-size: 24px;
    margin-bottom: 20px;
    color: var(--accent-color);
}

.info-content h3 {
    font-size: 18px;
    margin-top: 24px;
    margin-bottom: 12px;
    color: var(--text-primary);
}

.info-content p {
    line-height: 1.6;
    color: var(--text-secondary);
    margin-bottom: 16px;
}

.info-content ul {
    list-style: none;
    padding-left: 0;
}

.info-content li {
    padding: 8px 0;
    padding-left: 20px;
    position: relative;
    color: var(--text-secondary);
    line-height: 1.5;
}

.info-content li::before {
    content: '';
    position: absolute;
    left: 0;
    top: 14px;
    width: 8px;
    height: 8px;
    background: var(--accent-color);
    border-radius: 50%;
}

.info-content li strong {
    color: var(--text-primary);
}

.info-content kbd {
    display: inline-block;
    padding: 3px 8px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 4px;
    font-family: monospace;
    font-size: 14px;
    color: var(--accent-color);
}

.info-content .credit {
    margin-top: 24px;
    font-size: 14px;
    text-align: center;
    color: var(--text-secondary);
    font-style: italic;
}

.info-content .feedback-line {
    margin-top: 32px;
    font-size: 13px;
    text-align: center;
    color: rgba(255, 255, 255, 0.5);
}

.info-content .feedback-line a {
    color: rgba(255, 255, 255, 0.6);
    text-decoration: none;
    transition: color 0.2s ease;
}

.info-content .feedback-line a:hover {
    color: var(--accent-color);
    text-decoration: underline;
}

/* Expandable sections (details/summary) */
.info-content details {
    margin: 1rem 0;
    border-radius: 8px;
    transition: background 0.2s ease;
}

.info-content details[open] {
    background: rgba(255, 255, 255, 0.02);
    padding: 12px;
    margin: 1rem -12px;
}

.info-content summary {
    cursor: pointer;
    list-style: none;
    user-select: none;
    -webkit-user-select: none;
}

.info-content summary::-webkit-details-marker {
    display: none;
}

.info-content summary h3 {
    display: inline-block;
    margin: 0.5rem 0;
    transition: color 0.2s;
}

.info-content summary:hover h3 {
    color: var(--accent-color);
}

.info-content details[open] summary h3::after {
    content: ' ▴';
    color: var(--accent-color);
}

.info-content details:not([open]) summary h3::after {
    content: ' ▾';
    color: var(--text-secondary);
}

.info-content details p {
    margin-top: 12px;
}

/* Difficulty Selector */
.difficulty-selector {
    position: fixed;
    bottom: 30px;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 12px;
    z-index: 100;
}

.difficulty-buttons {
    display: flex;
    gap: 8px;
    padding: 8px 16px;
    background: var(--glass-bg);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border: 1px solid var(--glass-border);
    border-radius: 30px;
}

.difficulty-btn {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    border: 2px solid var(--glass-border);
    background: transparent;
    color: var(--text-secondary);
    font-size: 16px;
    font-weight: bold;
    cursor: pointer;
    transition: all 0.3s ease;
}

.difficulty-btn:hover {
    border-color: var(--accent-color);
    color: var(--accent-color);
}

.difficulty-btn.active {
    background: var(--accent-color);
    border-color: var(--accent-color);
    color: var(--bg-dark);
}

.difficulty-label {
    font-size: 14px;
    font-weight: 500;
    color: var(--accent-color);
    text-transform: uppercase;
    letter-spacing: 2px;
}

/* Fallback Message */
.fallback {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: var(--bg-dark);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: 40px;
    z-index: 1000;
}

.fallback.hidden {
    display: none;
}

.fallback h1 {
    font-size: 32px;
    margin-bottom: 20px;
    color: var(--accent-color);
}

.fallback p {
    font-size: 18px;
    color: var(--text-secondary);
    max-width: 500px;
}

/* Mobile Responsiveness */
@media (max-width: 768px) {
    .info-toggle {
        top: 15px;
        right: 15px;
        width: 40px;
        height: 40px;
        font-size: 18px;
    }

    .pause-toggle {
        top: 65px;
        right: 15px;
        width: 40px;
        height: 40px;
        font-size: 18px;
    }

    .info-content {
        margin: 20px;
        padding: 24px;
        max-height: calc(100vh - 40px);
    }

    .info-content h2 {
        font-size: 20px;
    }

    .difficulty-selector {
        bottom: 20px;
    }

    .difficulty-buttons {
        padding: 6px 12px;
        gap: 6px;
    }

    .difficulty-btn {
        width: 36px;
        height: 36px;
        font-size: 14px;
    }

    .difficulty-label {
        font-size: 12px;
    }
}

/* Scrollbar styling */
.info-content::-webkit-scrollbar {
    width: 8px;
}

.info-content::-webkit-scrollbar-track {
    background: rgba(255, 255, 255, 0.05);
    border-radius: 4px;
}

.info-content::-webkit-scrollbar-thumb {
    background: rgba(255, 255, 255, 0.2);
    border-radius: 4px;
}

.info-content::-webkit-scrollbar-thumb:hover {
    background: rgba(255, 255, 255, 0.3);
}

/* Screen Size Warning */
.size-warning {
    position: fixed;
    top: 20px;
    left: 50%;
    transform: translateX(-50%);
    background: var(--glass-bg);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border: 1px solid var(--glass-border);
    border-radius: 12px;
    padding: 16px 20px;
    z-index: 150;
    min-width: 280px;
    transition: opacity 0.3s ease, transform 0.3s ease;
}

.size-warning.hidden {
    opacity: 0;
    pointer-events: none;
    transform: translateX(-50%) translateY(-20px);
}

.size-warning-close {
    position: absolute;
    top: 8px;
    right: 10px;
    width: 24px;
    height: 24px;
    border: none;
    background: transparent;
    color: var(--text-secondary);
    font-size: 20px;
    cursor: pointer;
    transition: color 0.2s ease;
    line-height: 1;
    padding: 0;
}

.size-warning-close:hover {
    color: var(--text-primary);
}

.size-warning-content {
    text-align: center;
}

.size-warning-title {
    font-size: 14px;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 12px;
    text-transform: uppercase;
    letter-spacing: 1px;
}

.size-warning-metrics {
    display: flex;
    justify-content: center;
    gap: 24px;
    margin-bottom: 10px;
}

.size-metric {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 4px;
}

.metric-label {
    font-size: 11px;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 1px;
}

.metric-value {
    font-size: 24px;
    font-weight: 800;
    transition: color 0.3s ease;
}

.size-warning-hint {
    font-size: 11px;
    color: var(--text-secondary);
    margin-top: 4px;
}

/* Hide width/height metric when at 0% */
.size-metric.ok {
    opacity: 0.4;
}

.size-metric.ok .metric-value {
    color: #44ff88 !important;
}

@media (max-width: 480px) {
    .size-warning {
        left: 10px;
        right: 10px;
        transform: none;
        min-width: auto;
    }

    .size-warning.hidden {
        transform: translateY(-20px);
    }
}

/* Pause Notification */
.pause-notification {
    position: fixed;
    top: 160px;
    left: 50%;
    transform: translateX(-50%);
    background: var(--glass-bg);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border: 1px solid var(--glass-border);
    border-radius: 12px;
    padding: 14px 20px;
    z-index: 150;
    min-width: 240px;
    transition: opacity 0.3s ease, transform 0.3s ease;
}

.pause-notification.hidden {
    opacity: 0;
    pointer-events: none;
    transform: translateX(-50%) translateY(-20px);
}

.pause-notification-content {
    text-align: center;
}

.pause-notification-text {
    font-size: 13px;
    font-weight: 600;
    color: var(--accent-color);
    text-transform: uppercase;
    letter-spacing: 1px;
}

@media (max-width: 480px) {
    .pause-notification {
        left: 10px;
        right: 10px;
        transform: none;
        min-width: auto;
        top: 140px;
    }

    .pause-notification.hidden {
        transform: translateY(-20px);
    }
}