/* ========================================
   CSS变量定义
   ======================================== */
:root {
    /* 主色调 */
    --color-primary: #00ffff;
    --color-primary-dark: #0099cc;
    --color-secondary: #2196f3;
    --color-secondary-light: #00bfff;
    
    /* 状态颜色 */
    --color-success: #00ff00;
    --color-success-dark: #4caf50;
    --color-danger: #ff0000;
    --color-danger-light: #ff6666;
    --color-warning: #ffeb3b;
    --color-warning-dark: #ffd700;
    
    /* 骰子颜色 */
    --color-dice-red: #ff0000;
    --color-dice-red-light: #ff6347;
    --color-dice-blue: #0000ff;
    --color-dice-blue-light: #4682b4;
    --color-dice-yellow: #ffff00;
    --color-dice-yellow-dark: #ffd700;
    
    /* 背景色 */
    --color-bg-primary: #0f3460;
    --color-bg-overlay: rgba(0, 0, 0, 0.7);
    --color-bg-overlay-dark: rgba(0, 0, 0, 0.9);
    --color-bg-panel: rgba(10, 10, 30, 0.95);
    
    /* 边框色 */
    --color-border-primary: #00ffff;
    --color-border-secondary: #2196f3;
    --color-border-cell: #333333;
    
    /* 阴影 */
    --shadow-glow-primary: 0 0 5px var(--color-primary);
    --shadow-glow-primary-strong: 0 0 10px var(--color-primary), 0 0 20px var(--color-primary);
    --shadow-glow-secondary: 0 0 5px var(--color-secondary);
    
    /* 字体 */
    --font-primary: 'Orbitron', 'Courier New', monospace;
    --font-secondary: 'Courier New', monospace;
    
    /* 间距 */
    --spacing-xs: 5px;
    --spacing-sm: 10px;
    --spacing-md: 15px;
    --spacing-lg: 20px;
    --spacing-xl: 30px;
    
    /* 圆角 */
    --radius-sm: 5px;
    --radius-md: 8px;
    --radius-lg: 10px;
    --radius-xl: 15px;
    
    /* 过渡 */
    --transition-fast: 0.2s ease;
    --transition-normal: 0.3s ease;
    
    /* 响应式断点变量 */
    --container-max-width: 800px;
    --dice-size: 80px;
    --dice-size-mobile: 60px;
}

/* ========================================
   基础样式重置
   ======================================== */
*, *::before, *::after {
    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: var(--font-secondary);
    background: var(--color-bg-primary);
    color: #ffffff;
    min-height: 100vh;
    min-height: 100dvh; /* 动态视口高度，移动端适配 */
    overflow-x: hidden;
    position: relative;
    line-height: 1.5;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* ========================================
   太空背景
   ======================================== */
#spaceBackground {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: var(--color-bg-primary);
    z-index: -1;
    overflow: hidden;
}

#spaceBackground canvas {
    display: block;
}

/* ========================================
   屏幕布局
   ======================================== */
.screen {
    display: none;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    min-height: 100vh;
    min-height: 100dvh;
    padding: var(--spacing-lg);
    padding-bottom: calc(var(--spacing-lg) + env(safe-area-inset-bottom));
    position: relative;
}

.screen.active {
    display: flex;
}

/* 跳过链接（可访问性） - 仅键盘导航时显示 */
.skip-link {
    position: absolute;
    top: -100px;
    left: 0;
    background: var(--color-primary);
    color: #000;
    padding: var(--spacing-sm);
    z-index: 9999;
    text-decoration: none;
    font-weight: bold;
    opacity: 0;
    pointer-events: none;
}

.skip-link:focus-visible {
    top: 0;
    opacity: 1;
    pointer-events: auto;
}

/* ========================================
   游戏标题
   ======================================== */
.game-title {
    font-size: clamp(2rem, 8vw, 4rem);
    color: #ffffff;
    margin-bottom: var(--spacing-xl);
    font-weight: bold;
    letter-spacing: 4px;
    font-family: var(--font-primary);
    -webkit-text-stroke: 2px var(--color-primary);
    text-stroke: 2px var(--color-primary);
    text-shadow: 
        0 0 5px var(--color-primary),
        0 0 10px var(--color-primary),
        0 0 20px var(--color-primary),
        0 0 30px var(--color-primary);
    animation: titleGlow 3s ease-in-out infinite alternate;
    text-align: center;
}

@keyframes titleGlow {
    from {
        text-shadow: 
            0 0 5px var(--color-primary),
            0 0 10px var(--color-primary),
            0 0 20px var(--color-primary),
            0 0 30px var(--color-primary);
    }
    to {
        text-shadow: 
            0 0 10px var(--color-primary),
            0 0 20px var(--color-primary),
            0 0 30px var(--color-primary),
            0 0 40px var(--color-primary);
    }
}

/* ========================================
   按钮样式
   ======================================== */
.btn {
    background: linear-gradient(45deg, var(--color-primary), var(--color-primary-dark));
    color: #000000;
    border: 2px solid var(--color-primary);
    padding: var(--spacing-md) var(--spacing-xl);
    font-size: clamp(1rem, 3vw, 1.2rem);
    font-weight: bold;
    cursor: pointer;
    border-radius: var(--radius-sm);
    transition: all var(--transition-normal);
    font-family: var(--font-primary);
    text-shadow: 0 0 5px #ffffff;
    box-shadow: var(--shadow-glow-primary),
        inset 0 0 5px rgba(0, 255, 255, 0.3);
    animation: btnGlow 2s ease-in-out infinite alternate;
    touch-action: manipulation;
    user-select: none;
    -webkit-user-select: none;
    min-height: 44px; /* 可访问性：最小触摸目标 */
    min-width: 44px;
}

.btn:hover,
.btn:focus-visible {
    background: linear-gradient(45deg, var(--color-primary-dark), var(--color-primary));
    transform: scale(1.05);
    box-shadow: var(--shadow-glow-primary-strong),
        inset 0 0 10px rgba(0, 255, 255, 0.5);
    outline: none;
}

.btn:active,
.btn.touch-active {
    transform: scale(0.95);
    box-shadow: var(--shadow-glow-primary),
        inset 0 0 15px rgba(0, 255, 255, 0.7);
}

.btn:disabled,
.btn[aria-disabled="true"] {
    opacity: 0.5;
    cursor: not-allowed;
    transform: none;
    animation: none;
}

.btn:focus-visible {
    outline: 3px solid var(--color-warning);
    outline-offset: 2px;
}

@keyframes btnGlow {
    from {
        box-shadow: var(--shadow-glow-primary),
            inset 0 0 5px rgba(0, 255, 255, 0.3);
    }
    to {
        box-shadow: var(--shadow-glow-primary-strong),
            inset 0 0 10px rgba(0, 255, 255, 0.5);
    }
}

/* ========================================
   游戏信息面板
   ======================================== */
.game-info {
    width: 100%;
    max-width: var(--container-max-width);
    margin-bottom: var(--spacing-lg);
    padding: var(--spacing-md);
    background: var(--color-bg-overlay);
    border: 2px solid var(--color-border-secondary);
    border-radius: var(--radius-lg);
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: var(--spacing-sm);
}

.player-stats {
    display: flex;
    justify-content: space-around;
    gap: var(--spacing-lg);
    flex-wrap: wrap;
}

.stat {
    font-size: clamp(0.9rem, 2.5vw, 1.1rem);
    font-weight: bold;
    color: var(--color-warning);
}

.stat span {
    color: #ffffff;
}

.game-buttons {
    display: flex;
    gap: var(--spacing-sm);
}

/* ========================================
   地图容器
   ======================================== */
.map-container {
    width: 100%;
    max-width: var(--container-max-width);
    margin-bottom: var(--spacing-lg);
    padding: var(--spacing-lg);
    background: var(--color-bg-overlay);
    border: 2px solid var(--color-border-secondary);
    border-radius: var(--radius-lg);
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
}

.map {
    display: grid;
    grid-template-columns: repeat(10, 1fr);
    gap: var(--spacing-sm);
    width: 100%;
    min-width: 500px;
    aspect-ratio: 2.5 / 1;
}

/* ========================================
   格子样式
   ======================================== */
.cell {
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(255, 255, 255, 0.1);
    border: 2px solid var(--color-border-cell);
    border-radius: var(--radius-sm);
    font-size: clamp(0.7rem, 2vw, 0.9rem);
    font-weight: bold;
    transition: all var(--transition-normal);
    position: relative;
    overflow: hidden;
    aspect-ratio: 1;
}

.cell-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    width: 100%;
    height: 100%;
    padding: var(--spacing-xs);
}

.cell-number {
    font-size: clamp(0.5rem, 1.5vw, 0.7rem);
    color: #ffffff;
    margin-bottom: 2px;
    position: absolute;
    top: 4px;
    left: 50%;
    transform: translateX(-50%);
    z-index: 2; /* 确保在图标之上 */
}

.cell-icon {
    font-size: clamp(0.8rem, 2.5vw, 1.2rem);
    margin: var(--spacing-xs) 0;
    position: relative;
    z-index: 1;
}

.cell-direction {
    font-size: clamp(0.6rem, 1.8vw, 0.8rem);
    color: var(--color-warning);
    position: absolute;
    bottom: 4px;
    left: 50%;
    transform: translateX(-50%);
    z-index: 2; /* 确保在图标之上 */
}

/* 格子类型 */
.cell.normal { border-color: #555555; }
.cell.enemy { background: rgba(255, 0, 0, 0.2); border-color: #cc0000; }
.cell.chest { background: rgba(255, 215, 0, 0.2); border-color: #ccac00; }
.cell.boss { background: rgba(138, 43, 226, 0.2); border-color: #6a1b9a; }
.cell.start { background: rgba(0, 255, 0, 0.2); border-color: #00cc00; }

/* 最后一个 BOSS 格子单独占一整行 */
.map .cell.boss:last-child {
    grid-column: 1 / -1;
    /* 横向占 10 个普通格子的宽度，高度和普通格子一样 */
    aspect-ratio: 10 / 1;
}

.cell.target {
    animation: target-pulse 1s infinite;
    border-color: var(--color-warning);
    box-shadow: 0 0 10px rgba(255, 235, 59, 0.7);
}

.cell.player {
    background: rgba(74, 144, 226, 0.3);
    border-color: #4a90e2;
}

.cell.player::after {
    content: '👤';
    font-size: clamp(0.9rem, 2.5vw, 1.2rem);
    position: absolute;
    bottom: 4px;
    right: 4px;
    z-index: 1;
    pointer-events: none;
}

@keyframes target-pulse {
    0%, 100% { transform: scale(1); opacity: 1; }
    50% { transform: scale(1.05); opacity: 0.8; }
}

/* ========================================
   骰子样式
   ======================================== */
.dice-area {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-lg);
}

.dice {
    width: var(--dice-size);
    height: var(--dice-size);
    border: 3px solid var(--color-primary);
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: clamp(1.8rem, 5vw, 2.5rem);
    font-weight: bold;
    margin: 0 var(--spacing-sm);
    position: relative;
    overflow: hidden;
    box-shadow: var(--shadow-glow-primary);
    font-family: var(--font-primary);
    animation: diceGlow 3s ease-in-out infinite alternate;
}

.dice::before {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg, rgba(255, 255, 255, 0.2) 0%, rgba(255, 255, 255, 0) 100%);
    z-index: 1;
}

.dice span {
    position: relative;
    z-index: 2;
    text-shadow: 0 0 3px #ffffff;
}

.dice.yellow {
    background: linear-gradient(45deg, var(--color-dice-yellow), var(--color-dice-yellow-dark));
    color: #000000;
}

.dice.red {
    background: linear-gradient(45deg, var(--color-dice-red), var(--color-dice-red-light));
    color: #ffffff;
}

.dice.blue {
    background: linear-gradient(45deg, var(--color-dice-blue), var(--color-dice-blue-light));
    color: #ffffff;
}

.dice.rolling {
    animation: rollDice 0.5s ease-in-out;
}

.dice-container {
    display: flex;
    justify-content: center;
    gap: var(--spacing-xl);
    margin: var(--spacing-xl) 0;
}

.dice-icon {
    width: 50px;
    height: 50px;
    border: 2px solid var(--color-border-cell);
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    font-weight: bold;
}

.dice-icon.red {
    background: linear-gradient(45deg, var(--color-dice-red), var(--color-dice-red-light));
    color: #ffffff;
    border-color: var(--color-dice-red);
}

.dice-icon.blue {
    background: linear-gradient(45deg, var(--color-dice-blue), var(--color-dice-blue-light));
    color: #ffffff;
    border-color: var(--color-dice-blue);
}

@keyframes diceGlow {
    from { box-shadow: var(--shadow-glow-primary); }
    to { box-shadow: 0 0 10px var(--color-primary); }
}

@keyframes rollDice {
    0% { transform: rotate(0deg) scale(1); }
    25% { transform: rotate(90deg) scale(1.1); }
    50% { transform: rotate(180deg) scale(1); }
    75% { transform: rotate(270deg) scale(1.1); }
    100% { transform: rotate(360deg) scale(1); }
}

/* ========================================
   消息显示
   ======================================== */
.event-message,
.battle-message {
    width: 100%;
    max-width: var(--container-max-width);
    padding: var(--spacing-md);
    background: var(--color-bg-overlay);
    border: 2px solid var(--color-border-secondary);
    border-radius: var(--radius-lg);
    text-align: center;
    font-size: clamp(0.9rem, 2.5vw, 1.1rem);
    font-weight: bold;
    color: var(--color-warning);
    min-height: 50px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.battle-message {
    margin-top: var(--spacing-lg);
}

.event-message.flash,
.battle-message.flash {
    animation: flash 0.5s ease-in-out 1;
}

@keyframes flash {
    0% { opacity: 1; }
    50% { opacity: 0.5; }
    100% { opacity: 1; }
}

/* ========================================
   战斗界面
   ======================================== */
.enemy-section,
.player-section {
    display: flex;
    justify-content: center;
    width: 100%;
}

.enemy-section { margin-bottom: var(--spacing-xl); }
.player-section { margin-top: var(--spacing-xl); }

.battle-field {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-lg);
    width: 100%;
}

.enemy-info,
.player-info {
    width: 100%;
    max-width: 400px;
    padding: var(--spacing-lg);
    background: var(--color-bg-overlay);
    border: 2px solid var(--color-border-secondary);
    border-radius: var(--radius-lg);
    text-align: center;
}

.enemy-info h3,
.player-info h3 {
    color: var(--color-warning);
    margin-bottom: var(--spacing-md);
    font-size: clamp(1.2rem, 3vw, 1.5rem);
}

/* 血条 */
.health-bar-container {
    width: 100%;
    height: 20px;
    background: rgba(0, 0, 0, 0.5);
    border-radius: var(--radius-lg);
    margin: var(--spacing-sm) 0;
    overflow: hidden;
    border: 2px solid var(--color-primary);
    position: relative;
    box-shadow: var(--shadow-glow-primary);
}

.health-bar {
    height: 100%;
    transition: width var(--transition-normal);
    border-radius: var(--radius-md);
    position: absolute;
    top: 0;
}

.enemy-health {
    background: linear-gradient(90deg, var(--color-danger), var(--color-dice-red-light));
    left: 0;
    box-shadow: 0 0 3px var(--color-danger);
}

.player-health {
    background: linear-gradient(90deg, var(--color-success), var(--color-success-dark));
    left: 0;
    box-shadow: 0 0 3px var(--color-success);
}

.player-shield {
    background: linear-gradient(90deg, var(--color-secondary-light), #1e90ff);
    right: 0;
    z-index: 1;
    box-shadow: 0 0 3px var(--color-secondary-light);
}

.health-damage {
    color: var(--color-danger) !important;
    animation: shake 0.5s ease-in-out;
}

.shield-value { color: var(--color-secondary-light) !important; }
.shield-block { animation: shake 0.5s ease-in-out; }

@keyframes shake {
    0%, 100% { transform: translateX(0); }
    10%, 30%, 50%, 70%, 90% { transform: translateX(-5px); }
    20%, 40%, 60%, 80% { transform: translateX(5px); }
}

.battle-buttons {
    position: absolute;
    top: var(--spacing-sm);
    left: var(--spacing-sm);
    display: flex;
    gap: var(--spacing-sm);
}

.battle-buttons .btn {
    font-size: 0.8rem;
    padding: 8px 16px;
    background: var(--color-bg-overlay);
    border: 1px solid var(--color-border-secondary);
    color: var(--color-border-secondary);
}

/* ========================================
   升级界面
   ======================================== */
.upgrade-options {
    display: flex;
    gap: var(--spacing-xl);
    margin-top: var(--spacing-xl);
    flex-wrap: wrap;
    justify-content: center;
}

.upgrade-btn {
    flex: 1;
    min-width: 200px;
    max-width: 300px;
    background: var(--color-bg-overlay);
    border: 2px solid var(--color-primary);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    cursor: pointer;
    transition: all var(--transition-normal);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-md);
    font-family: var(--font-primary);
    box-shadow: var(--shadow-glow-primary),
        inset 0 0 5px rgba(0, 255, 255, 0.3);
    animation: btnGlow 2s ease-in-out infinite alternate;
}

.upgrade-btn:hover,
.upgrade-btn:focus-visible {
    background: rgba(0, 255, 255, 0.1);
    transform: translateY(-5px);
    box-shadow: var(--shadow-glow-primary-strong),
        inset 0 0 10px rgba(0, 255, 255, 0.5);
    outline: none;
}

.upgrade-btn:focus-visible {
    outline: 3px solid var(--color-warning);
    outline-offset: 2px;
}

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

.upgrade-info h3 {
    color: var(--color-warning);
    margin-bottom: var(--spacing-sm);
    font-size: clamp(1rem, 2.5vw, 1.3rem);
}

.upgrade-info p {
    margin: var(--spacing-xs) 0;
    color: #ffffff;
    font-size: clamp(0.9rem, 2vw, 1rem);
}

/* ========================================
   结束界面
   ======================================== */
#endScreen {
    gap: var(--spacing-lg);
}

#endScreen h1 {
    font-size: clamp(2rem, 6vw, 3rem);
    margin-bottom: var(--spacing-lg);
}

#endScreen .btn {
    min-width: 150px;
    margin: 0 var(--spacing-sm);
}

#endMessage {
    font-size: clamp(1rem, 3vw, 1.5rem);
    margin-bottom: var(--spacing-xl);
    color: #4a90e2;
    text-align: center;
    max-width: 600px;
    padding: 0 var(--spacing-md);
}

/* ========================================
   自动技能界面
   ======================================== */
.skill-points {
    margin: var(--spacing-lg) 0;
    color: var(--color-warning);
    font-size: clamp(1rem, 2.5vw, 1.2rem);
}

.auto-skill-container {
    width: 100%;
    max-width: 1000px;
    margin: var(--spacing-xl) 0;
    padding: var(--spacing-lg);
    background: var(--color-bg-overlay);
    border: 2px solid var(--color-border-secondary);
    border-radius: var(--radius-lg);
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
}

.branch-description {
    display: flex;
    justify-content: space-around;
    align-items: center;
    margin-bottom: var(--spacing-xl);
    width: 100%;
    flex-wrap: wrap;
    gap: var(--spacing-md);
}

.branch-label {
    font-size: clamp(0.9rem, 2.5vw, 1.2rem);
    font-weight: bold;
    text-align: center;
    padding: var(--spacing-sm) var(--spacing-lg);
    background: rgba(0, 0, 0, 0.5);
    border-radius: var(--radius-md);
    border: 2px solid;
    flex: 1;
    min-width: 150px;
    max-width: 300px;
}

.blue-label {
    border-color: var(--color-border-secondary);
    color: var(--color-border-secondary);
    text-shadow: 0 0 5px rgba(33, 150, 243, 0.7);
}

.red-label {
    border-color: #f44336;
    color: #f44336;
    text-shadow: 0 0 5px rgba(244, 67, 54, 0.7);
}

.auto-skill-tree {
    display: flex;
    justify-content: space-around;
    align-items: flex-start;
    flex-wrap: wrap;
    gap: 50px;
}

.branch {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-lg);
}

.tree-node {
    width: 100%;
    max-width: 300px;
    min-width: 200px;
    padding: var(--spacing-lg);
    background: rgba(255, 255, 255, 0.1);
    border: 2px solid #555;
    border-radius: var(--radius-lg);
    cursor: pointer;
    transition: all var(--transition-normal);
}

.tree-node:hover,
.tree-node:focus-visible {
    transform: translateY(-5px);
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.3);
    outline: none;
}

.tree-node:focus-visible {
    outline: 3px solid var(--color-warning);
    outline-offset: 2px;
}

.tree-node.activated {
    background: rgba(76, 175, 80, 0.3);
    border-color: var(--color-success-dark);
    box-shadow: 0 0 10px rgba(76, 175, 80, 0.5);
}

.tree-node.locked {
    opacity: 0.5;
    cursor: not-allowed;
}

.tree-node.locked:hover {
    transform: none;
}

.node-content {
    text-align: center;
}

.node-title {
    font-size: clamp(0.9rem, 2vw, 1.1rem);
    font-weight: bold;
    color: #ffffff;
}

.auto-skill-buttons {
    display: flex;
    justify-content: center;
    gap: var(--spacing-lg);
    margin-top: var(--spacing-xl);
    flex-wrap: wrap;
}

/* ========================================
   提示弹窗
   ======================================== */
.tip-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: var(--color-bg-overlay-dark);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    backdrop-filter: blur(5px);
    padding: var(--spacing-lg);
}

.tip-content {
    background: var(--color-bg-panel);
    border: 2px solid var(--color-primary);
    border-radius: var(--radius-xl);
    padding: var(--spacing-xl);
    max-width: 500px;
    width: 100%;
    text-align: center;
    box-shadow: 0 0 20px rgba(0, 255, 255, 0.5);
    max-height: 80vh;
    overflow-y: auto;
}

.tip-content h2 {
    color: var(--color-primary);
    font-size: clamp(1.5rem, 4vw, 2rem);
    margin-bottom: var(--spacing-lg);
    text-shadow: 0 0 10px rgba(0, 255, 255, 0.7);
}

.tip-content p {
    color: #ffffff;
    font-size: clamp(1rem, 2.5vw, 1.2rem);
    margin-bottom: var(--spacing-lg);
}

.tip-content ul {
    list-style: none;
    padding: 0;
    margin: var(--spacing-lg) 0;
}

.tip-content li {
    color: #ffffff;
    font-size: clamp(0.9rem, 2.5vw, 1.1rem);
    margin: var(--spacing-sm) 0;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
}

.tip-content .btn {
    margin-top: var(--spacing-lg);
}

/* ========================================
   音量控制
   ======================================== */
.volume-control {
    position: fixed;
    right: var(--spacing-lg);
    background: var(--color-bg-overlay);
    padding: var(--spacing-sm) var(--spacing-md);
    border: 2px solid var(--color-border-secondary);
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    z-index: 1000;
    font-family: var(--font-primary);
    box-shadow: var(--shadow-glow-secondary);
}

#soundEffectControl { bottom: 70px; }
#volumeControl { bottom: var(--spacing-lg); }

.volume-label {
    color: var(--color-warning);
    font-weight: bold;
    font-size: 0.9rem;
}

/* 通用滑块样式 */
.volume-control input[type="range"] {
    width: 100px;
    height: 5px;
    -webkit-appearance: none;
    appearance: none;
    background: rgba(255, 255, 255, 0.3);
    border-radius: var(--radius-sm);
    outline: none;
}

.volume-control input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 15px;
    height: 15px;
    background: var(--color-border-secondary);
    border: 2px solid #ffffff;
    border-radius: 50%;
    cursor: pointer;
    box-shadow: var(--shadow-glow-secondary);
}

.volume-control input[type="range"]::-moz-range-thumb {
    width: 15px;
    height: 15px;
    background: var(--color-border-secondary);
    border: 2px solid #ffffff;
    border-radius: 50%;
    cursor: pointer;
    box-shadow: var(--shadow-glow-secondary);
}

.volume-control input[type="range"]:focus-visible {
    outline: 2px solid var(--color-warning);
    outline-offset: 2px;
}

.volume-value {
    color: #ffffff;
    font-weight: bold;
    font-size: 0.8rem;
    width: 45px;
    text-align: right;
}

/* ========================================
   帮助按钮和界面
   ======================================== */
.help-btn {
    position: fixed;
    top: var(--spacing-lg);
    right: var(--spacing-lg);
    width: 44px;
    height: 44px;
    border-radius: 50%;
    background: linear-gradient(45deg, var(--color-border-secondary), var(--color-secondary-light));
    color: white;
    font-size: 24px;
    font-weight: bold;
    border: none;
    cursor: pointer;
    z-index: 1000;
    box-shadow: 0 0 10px rgba(33, 150, 243, 0.7);
    transition: all var(--transition-normal);
}

.help-btn:hover,
.help-btn:focus-visible {
    transform: scale(1.1);
    box-shadow: 0 0 15px rgba(33, 150, 243, 1);
    outline: none;
}

.help-btn:focus-visible {
    outline: 3px solid var(--color-warning);
    outline-offset: 2px;
}

.help-screen {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: var(--color-bg-overlay-dark);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 2000;
    backdrop-filter: blur(5px);
    padding: var(--spacing-lg);
}

.help-screen .help-content {
    background: var(--color-bg-panel);
    border: 2px solid var(--color-primary);
    border-radius: var(--radius-xl);
    padding: var(--spacing-xl);
    max-width: 600px;
    width: 100%;
    max-height: 80vh;
    overflow-y: auto;
    box-shadow: 0 0 20px rgba(0, 255, 255, 0.5);
}

.help-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--spacing-lg);
    padding-bottom: var(--spacing-sm);
    border-bottom: 1px solid rgba(0, 255, 255, 0.3);
}

.help-header h2 {
    color: var(--color-primary);
    font-size: clamp(1.5rem, 4vw, 2rem);
    margin: 0;
    text-shadow: 0 0 10px rgba(0, 255, 255, 0.7);
}

.close-btn {
    background: none;
    border: none;
    color: #ffffff;
    font-size: 2rem;
    cursor: pointer;
    transition: color var(--transition-normal);
    padding: var(--spacing-xs);
    line-height: 1;
    min-width: 44px;
    min-height: 44px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.close-btn:hover,
.close-btn:focus-visible {
    color: var(--color-primary);
    text-shadow: 0 0 10px rgba(0, 255, 255, 0.7);
    outline: none;
}

.close-btn:focus-visible {
    outline: 2px solid var(--color-warning);
    outline-offset: 2px;
}

.help-sections {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-lg);
}

.help-section {
    background: rgba(0, 0, 0, 0.5);
    border: 1px solid rgba(33, 150, 243, 0.5);
    border-radius: var(--radius-lg);
    padding: var(--spacing-md);
}

.help-section h3 {
    color: var(--color-border-secondary);
    font-size: clamp(1rem, 2.5vw, 1.3rem);
    margin: 0 0 var(--spacing-sm) 0;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.help-lock {
    font-size: 1rem;
    opacity: 0.7;
}

.help-content-locked {
    color: #888888;
    font-style: italic;
}

.help-content-unlocked {
    color: #ffffff;
}

.help-content-unlocked p { margin: var(--spacing-sm) 0; }
.help-content-unlocked ul { margin: var(--spacing-sm) 0; padding-left: var(--spacing-lg); }
.help-content-unlocked li { margin: var(--spacing-xs) 0; }

/* 滚动条 */
.help-screen .help-content::-webkit-scrollbar { width: 8px; }
.help-screen .help-content::-webkit-scrollbar-track {
    background: rgba(0, 0, 0, 0.3);
    border-radius: 4px;
}
.help-screen .help-content::-webkit-scrollbar-thumb {
    background: rgba(33, 150, 243, 0.7);
    border-radius: 4px;
}
.help-screen .help-content::-webkit-scrollbar-thumb:hover {
    background: rgba(33, 150, 243, 1);
}

/* ========================================
   错误消息
   ======================================== */
.error-message {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    background: rgba(244, 67, 54, 0.9);
    color: white;
    padding: var(--spacing-xl);
    border-radius: var(--radius-lg);
    z-index: 9999;
    text-align: center;
    font-size: 1.2rem;
}

/* ========================================
   响应式设计 - 平板
   ======================================== */
@media (max-width: 768px) {
    :root {
        --dice-size: 70px;
    }

    .player-stats {
        flex-direction: column;
        gap: var(--spacing-sm);
        text-align: center;
    }

    .game-info {
        flex-direction: column;
        align-items: center;
    }

    .map {
        grid-template-columns: repeat(5, 1fr);
        min-width: auto;
    }

    .battle-info {
        flex-direction: column;
    }

    .upgrade-options {
        flex-direction: column;
        width: 100%;
    }

    .upgrade-btn {
        max-width: 100%;
    }

    .auto-skill-tree {
        flex-direction: column;
        align-items: center;
    }

    .branch {
        width: 100%;
    }

    .tree-node {
        max-width: 100%;
    }

    .branch-label {
        max-width: 100%;
    }

    .volume-control {
        right: var(--spacing-sm);
        padding: 8px 12px;
    }

    .volume-control input[type="range"] {
        width: 80px;
    }

    #soundEffectControl { bottom: 60px; }
    #volumeControl { bottom: var(--spacing-sm); }

    .help-btn {
        top: var(--spacing-sm);
        right: var(--spacing-sm);
    }
}

/* ========================================
   响应式设计 - 手机
   ======================================== */
@media (max-width: 480px) {
    :root {
        --dice-size: 60px;
        --spacing-lg: 15px;
        --spacing-xl: 20px;
    }

    .map {
        grid-template-columns: repeat(4, 1fr);
        gap: 5px;
    }

    .cell {
        font-size: 0.6rem;
    }

    .btn {
        padding: 12px 20px;
    }

    .tree-node {
        padding: var(--spacing-md);
    }

    .auto-skill-buttons {
        flex-direction: column;
        width: 100%;
        padding: 0 var(--spacing-md);
    }

    .auto-skill-buttons .btn {
        width: 100%;
    }

    #endScreen .btn {
        min-width: auto;
        width: 100%;
        max-width: 200px;
    }

    .dice-container {
        gap: var(--spacing-lg);
    }
}

/* ========================================
   减少动画（可访问性）
   ======================================== */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }

    .dice.rolling {
        animation: none;
    }

    .game-title,
    .btn {
        animation: none;
    }
}

/* ========================================
   高对比度模式（可访问性）
   ======================================== */
@media (prefers-contrast: high) {
    :root {
        --color-bg-overlay: rgba(0, 0, 0, 0.9);
        --color-border-cell: #ffffff;
    }

    .btn {
        border-width: 3px;
    }

    .cell {
        border-width: 3px;
    }
}

/* ========================================
   打印样式
   ======================================== */
@media print {
    #spaceBackground,
    .volume-control,
    .help-btn,
    .btn {
        display: none;
    }

    body {
        background: white;
        color: black;
    }
}