/* CSS变量定义 - 支持主题切换 */
:root {
    /* 现代主题 */
    --bg-primary: #0a0e27;
    --bg-secondary: #151933;
    --bg-game: #1a1f3a;
    --border-color: #3a4574;
    --text-primary: #ffffff;
    --text-secondary: #a8b2d1;
    --accent-primary: #64ffda;
    --accent-secondary: #f06292;
    --success-color: #4caf50;
    --warning-color: #ff9800;
    --danger-color: #f44336;
    --shadow-color: rgba(0, 0, 0, 0.5);
}

/* 全局样式重置 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: linear-gradient(135deg, var(--bg-primary) 0%, var(--bg-secondary) 100%);
    color: var(--text-primary);
    overflow: hidden;
    user-select: none;
    -webkit-user-select: none;
    -webkit-tap-highlight-color: transparent;
    touch-action: none;
    height: 100vh;
}

/* 游戏容器 */
.game-container {
    position: relative;
    width: 100vw;
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
}

/* 游戏画布 */
.game-canvas {
    background: var(--bg-game);
    border: 2px solid var(--border-color);
    border-radius: 12px;
    box-shadow: 
        0 0 40px var(--shadow-color),
        inset 0 0 20px rgba(100, 255, 218, 0.1);
    max-width: min(90vmin, 800px);
    max-height: min(90vmin, 800px);
    width: 100%;
    height: 100%;
    aspect-ratio: 1;
    
    /* 像素完美渲染 */
    image-rendering: -moz-crisp-edges;
    image-rendering: -webkit-crisp-edges;
    image-rendering: pixelated;
    image-rendering: crisp-edges;
}

/* 游戏UI层 */
.game-ui {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: 10;
}

/* 分数面板 */
.score-panel {
    position: absolute;
    top: 20px;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    gap: 40px;
    background: rgba(26, 31, 58, 0.9);
    padding: 12px 24px;
    border-radius: 8px;
    backdrop-filter: blur(10px);
    border: 1px solid var(--border-color);
}

.current-score, .high-score {
    display: flex;
    flex-direction: column;
    align-items: center;
}

.score-panel .label {
    font-size: 12px;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 1px;
}

.score-panel #score,
.score-panel #highScore {
    font-size: 24px;
    font-weight: bold;
    color: var(--accent-primary);
    font-variant-numeric: tabular-nums;
}

/* 游戏信息 */
.game-info {
    position: absolute;
    bottom: 20px;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    gap: 20px;
    font-size: 14px;
    color: var(--text-secondary);
}

.level, .speed-indicator {
    background: rgba(26, 31, 58, 0.9);
    padding: 8px 16px;
    border-radius: 6px;
    backdrop-filter: blur(10px);
    border: 1px solid var(--border-color);
}

/* 菜单容器 */
.menu-container {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
    background: rgba(10, 14, 39, 0.95);
    backdrop-filter: blur(20px);
    z-index: 100;
    transition: opacity 0.3s ease;
}

.menu-container.hidden {
    display: none;
}

/* 通用隐藏类 */
.hidden {
    display: none !important;
}

.menu-content {
    background: var(--bg-secondary);
    padding: 40px;
    border-radius: 16px;
    border: 2px solid var(--border-color);
    box-shadow: 0 20px 60px var(--shadow-color);
    max-width: 90%;
    width: 400px;
    animation: menuSlideIn 0.3s ease-out;
}

@keyframes menuSlideIn {
    from {
        transform: translateY(-20px);
        opacity: 0;
    }
    to {
        transform: translateY(0);
        opacity: 1;
    }
}

/* 游戏标题 */
.game-title {
    font-size: 32px;
    text-align: center;
    margin-bottom: 8px;
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.game-subtitle {
    text-align: center;
    color: var(--text-secondary);
    margin-bottom: 30px;
}

/* 按钮样式 */
.menu-buttons {
    display: flex;
    flex-direction: column;
    gap: 12px;
    margin: 30px 0;
}

.btn {
    padding: 14px 24px;
    font-size: 16px;
    font-weight: 600;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.3s ease;
    text-transform: uppercase;
    letter-spacing: 1px;
}

.btn-primary {
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
    color: var(--bg-primary);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 30px rgba(100, 255, 218, 0.3);
}

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

.btn-secondary:hover {
    background: var(--border-color);
    transform: translateY(-2px);
}

/* 游戏统计 */
.game-stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(100px, 1fr));
    gap: 20px;
    margin: 30px 0;
}

.stat-item {
    text-align: center;
    padding: 15px;
    background: rgba(58, 69, 116, 0.3);
    border-radius: 8px;
    border: 1px solid var(--border-color);
}

.stat-label {
    display: block;
    font-size: 12px;
    color: var(--text-secondary);
    margin-bottom: 8px;
    text-transform: uppercase;
}

.stat-value {
    display: block;
    font-size: 24px;
    font-weight: bold;
    color: var(--accent-primary);
}

/* 设置面板 */
.settings-group {
    margin: 30px 0;
}

.setting-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px 0;
    border-bottom: 1px solid rgba(58, 69, 116, 0.5);
}

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

.setting-item span:first-child {
    color: var(--text-secondary);
}

.setting-item select,
.setting-item input[type="range"] {
    background: var(--bg-game);
    border: 1px solid var(--border-color);
    color: var(--text-primary);
    padding: 8px 12px;
    border-radius: 6px;
    outline: none;
}

.setting-item input[type="range"] {
    width: 120px;
    cursor: pointer;
}

/* 帮助内容 */
.help-content {
    margin: 30px 0;
}

.control-group {
    margin-bottom: 25px;
}

.control-group h3 {
    color: var(--accent-primary);
    margin-bottom: 10px;
    font-size: 16px;
}

.control-group p {
    color: var(--text-secondary);
    line-height: 1.6;
    margin-bottom: 5px;
}

/* 暂停覆盖层 */
.pause-overlay {
    display: none; /* 默认隐藏 */
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    background: rgba(26, 31, 58, 0.95);
    padding: 30px 50px;
    border-radius: 12px;
    border: 2px solid var(--border-color);
    text-align: center;
    z-index: 50;
    backdrop-filter: blur(10px);
}

/* 显示暂停覆盖层 */
.pause-overlay:not(.hidden) {
    display: block;
}

.pause-overlay h2 {
    color: var(--accent-primary);
    margin-bottom: 10px;
}

.pause-overlay p {
    color: var(--text-secondary);
}

/* 移动端适配 */
@media (max-width: 768px) {
    .game-canvas {
        max-width: 95vmin;
        max-height: 95vmin;
    }
    
    .score-panel {
        top: 10px;
        padding: 8px 16px;
        gap: 20px;
    }
    
    .score-panel .label {
        font-size: 10px;
    }
    
    .score-panel #score,
    .score-panel #highScore {
        font-size: 20px;
    }
    
    .menu-content {
        padding: 30px 20px;
        width: 90%;
    }
    
    .game-title {
        font-size: 28px;
    }
    
    .btn {
        padding: 12px 20px;
        font-size: 14px;
    }
    
    .game-info {
        bottom: 10px;
        font-size: 12px;
    }
}

/* 主题切换动画 */
body.theme-transition,
body.theme-transition *,
body.theme-transition *:before,
body.theme-transition *:after {
    transition: all 0.3s !important;
    transition-delay: 0 !important;
}

/* 经典主题 */
body.theme-classic {
    --bg-primary: #2d2d2d;
    --bg-secondary: #3d3d3d;
    --bg-game: #000000;
    --border-color: #00ff00;
    --accent-primary: #00ff00;
    --accent-secondary: #ffff00;
}

/* 霓虹主题 */
body.theme-neon {
    --bg-primary: #0a0a0a;
    --bg-secondary: #1a0a1a;
    --bg-game: #000000;
    --border-color: #ff00ff;
    --accent-primary: #00ffff;
    --accent-secondary: #ff00ff;
}

/* 自然主题 */
body.theme-nature {
    --bg-primary: #2c5f2d;
    --bg-secondary: #4a7c59;
    --bg-game: #1a3a1a;
    --border-color: #97bc62;
    --accent-primary: #97bc62;
    --accent-secondary: #f4a460;
}