:root {
    /* 坦克相关常量 */
    --tank-width: 60px;
    --tank-height: 40px;
    --tank-total-height: 60px;
    --tank-bottom: 150px;
    --barrel-width: 40px;
    --barrel-height: 8px;
    --barrel-top-offset: 16px;
    --barrel-extend: 20px;
    --bullet-size: 10px;
    --explosion-size: 60px;
    --big-explosion-size: 120px;
}

body {
    margin: 0;
    padding: 0;
    background-color: #000;
    font-family: 'Courier New', monospace;
    overflow: hidden;
    color: #fff;
}

#gameContainer {
    width: 100vw;
    height: 100vh;
    position: relative;
    background-color: #16676a;  
    min-width: 400px;
}

/* 设置界面 */
#setupScreen {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    background-color: #333;
    border: 3px solid #0f0;
    padding: 30px;
    text-align: left;
    box-shadow: 0 0 20px #0f0;
    max-height: 80vh;
    overflow-y: auto;
    min-width: 500px;
}

#setupScreen h1 {
    color: #0f0;
    margin-bottom: 20px;
    text-shadow: 2px 2px 4px #000;
}

.setup-option {
    color: #fff;
}

.setup-option label {
    margin-bottom: 5px;
    font-weight: bold;
    font-size:medium;
    color: #0f0;
}

div.setup-nickname {
    padding: 10px;
    border: 0px;
    background-color: rgb(28, 27, 27);
    font-size: 14px;
    font-family: 'Courier New', monospace;
}

.setup-nickname .setup-option {
    margin-left: 10px;
}

.option-group {
    margin: 10px 0;
    padding: 10px 15px;
    border: 0px solid #555;
    border-radius: 3px;
    background-color: #444;
}

.option-group h3 {
    margin: 0 0 10px 0;
    color: #0f0;
    font-size: 18px;
}

.sub-options {
    margin-left: 20px;
    margin-top: 10px;
}

.sub-options label {
    font-weight: normal;
    color: #fff;
    margin-right: 10px;
    display: inline;
}

.radio-group {
    display: flex;
    flex-wrap: wrap;
    gap: 15px;
    margin-top: 5px;
}

.radio-item {
    display: flex;
    align-items: center;
    margin-right: 15px;
}

.radio-item input[type="radio"] {
    margin-right: 5px;
}

.disabled-group {
    opacity: 0.5;
    pointer-events: none;
}

.setup-option input[type="checkbox"]:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

/* 昵称输入框样式 */
.setup-option input[type="text"] {
    background-color: #222;
    color: #0f0;
    border: 1px solid #0f0;
    padding: 6px 6px;
    font-size: 14px;
    font-family: 'Courier New', monospace;
    border-radius: 5px;
    margin-left: 10px;
    width: 40px;
}

.setup-option input[type="text"]:focus {
    outline: none;
    border-color: #0ff;
    box-shadow: 0 0 10px #0ff;
}

.setup-option input[type="text"]::placeholder {
    color: #666;
}

#startBtn {
    background-color: #0f0;
    color: #000;
    border: none;
    padding: 15px 30px;
    font-size: 20px;
    font-weight: bold;
    cursor: pointer;
    margin-top: 20px;
    box-shadow: 0 0 10px #0f0;
    font-family: 'Courier New', monospace;
}

#startBtn:hover {
    background-color: #0a0;
    transform: scale(1.05);
}

/* 游戏界面 */
#gameScreen {
    display: none;
    width: 100%;
    height: 100%;
    position: relative;
}

/* 战场区域 */
#battleField {
    position: relative;
    width: 100%;
    height: 60%;
    background-color: #222;
    border-bottom: 2px solid #666;
}

/* 坦克 */
.tank {
    position: absolute;
    width: var(--tank-width);
    height: var(--tank-total-height);
}

#playerTank {
    bottom: var(--tank-bottom);
    left: 100px;
}

#enemyTank {
    bottom: var(--tank-bottom);
    right: 100px;
    transition: all 0.3s ease;
    transform-origin: bottom center;
}

.tank-body {
    width: var(--tank-width);
    height: var(--tank-height);
    background-color: #0a0;
    position: relative;
    border: 2px solid #060;
}

.tank-barrel {
    width: var(--barrel-width);
    height: var(--barrel-height);
    background-color: #080;
    position: absolute;
    top: var(--barrel-top-offset);
    right: calc(-1 * var(--barrel-extend));
}

#enemyTank .tank-body {
    background-color: #a00;
    border-color: #600;
}

#enemyTank .tank-barrel {
    background-color: #800;
    left: calc(-1 * var(--barrel-extend));
    right: auto;
}

/* 血条样式 */
.health-bar {
    position: absolute;
    width: 100%;
    height: 10px;
    top: -20px;
    left: 0;
    background-color: #333;
    border: 2px solid #fff;
    border-radius: 5px;
}

.health-bar-fill {
    height: 100%;
    background-color: #0f0;
    border-radius: 3px;
    transition: width 0.3s ease;
}

.health-bar-fill.medium {
    background-color: #ff0;
}

.health-bar-fill.low {
    background-color: #f00;
}

/* 坦克爆炸动画 */
@keyframes tankExplode {
    0% {
        transform: scale(1) rotate(0deg);
    }
    25% {
        transform: scale(1.2) rotate(10deg);
    }
    50% {
        transform: scale(1.1) rotate(-10deg);
    }
    75% {
        transform: scale(1.3) rotate(5deg);
        opacity: 1;
    }
    100% {
        transform: scale(0) rotate(360deg);
        opacity: 0;
    }
}

.tank-exploding {
    animation: tankExplode 1s ease-out forwards;
}

/* 大爆炸效果 */
.big-explosion {
    position: absolute;
    width: var(--big-explosion-size);
    height: var(--big-explosion-size);
    background: radial-gradient(circle, #ff0, #f00, transparent);
    border-radius: 50%;
    animation: bigExplode 1s ease-out forwards;
}

@keyframes bigExplode {
    0% {
        transform: scale(0.5);
        opacity: 1;
    }
    50% {
        transform: scale(1.5);
    }
    100% {
        transform: scale(2);
        opacity: 0;
    }
}

/* 敌方坦克等级样式 */
.enemy-level {
    position: absolute;
    top: -40px;
    left: 50%;
    transform: translateX(-50%);
    color: #f00;
    font-size: 20px;
    font-weight: bold;
    text-shadow: 2px 2px 4px #000;
}

/* 玩家昵称样式 */
.player-nickname {
    position: absolute;
    top: -46px;
    left: 50%;
    transform: translateX(-50%);
    color: #0f0;
    font-size: 20px;
    font-weight: bold;
    text-shadow: 2px 2px 4px #000;
    white-space: nowrap;
    min-width: max-content;
}

/* 奥特曼模式样式 */
.ultraman-mode #playerTank .tank-body {
    background: transparent;
    border: none;
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 40px;
    line-height: 1;
}

.ultraman-mode #playerTank .tank-body::before {
    content: "🔴";
    position: absolute;
    font-size: 40px;
    z-index: 1;
}

.ultraman-mode #playerTank .tank-body::after {
    content: "🦸‍♂️";
    position: absolute;
    font-size: 35px;
    z-index: 2;
    transform: translateX(2px);
}

.ultraman-mode #enemyTank .tank-body {
    background: transparent;
    border: none;
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 40px;
    line-height: 1;
}

.ultraman-mode #enemyTank .tank-body::before {
    content: "👹";
    position: absolute;
    font-size: 40px;
    z-index: 1;
}

/* 奥特曼模式下隐藏炮管 */
.ultraman-mode .tank-barrel {
    display: none;
}

/* 奥特曼模式特效 */
.ultraman-mode #playerTank {
    filter: drop-shadow(0 0 10px #00ff00);
    animation: ultramanGlow 2s infinite alternate;
}

.ultraman-mode #enemyTank {
    filter: drop-shadow(0 0 10px #ff0000);
    animation: monsterGlow 2s infinite alternate;
}

@keyframes ultramanGlow {
    0% {
        filter: drop-shadow(0 0 5px #00ff00) hue-rotate(0deg);
    }
    100% {
        filter: drop-shadow(0 0 15px #00ff00) hue-rotate(60deg);
    }
}

@keyframes monsterGlow {
    0% {
        filter: drop-shadow(0 0 5px #ff0000) hue-rotate(0deg);
    }
    100% {
        filter: drop-shadow(0 0 15px #ff0000) hue-rotate(30deg);
    }
}

/* 奥特曼模式的炮弹样式 */
.ultraman-mode .bullet {
    background: radial-gradient(circle, #fff, #00ff00, #0000ff);
    border-radius: 50%;
    box-shadow: 0 0 20px #00ff00;
    animation: ultramanBullet 0.5s infinite alternate;
}

.ultraman-mode .enemy-bullet {
    background: radial-gradient(circle, #fff, #ff0000, #800080);
    box-shadow: 0 0 20px #ff0000;
    animation: monsterBullet 0.5s infinite alternate;
}

@keyframes ultramanBullet {
    0% { transform: scale(1) rotate(0deg); }
    100% { transform: scale(1.2) rotate(180deg); }
}

@keyframes monsterBullet {
    0% { transform: scale(1) rotate(0deg); }
    100% { transform: scale(1.2) rotate(-180deg); }
}

/* 奥特曼模式的爆炸效果 */
.ultraman-mode .explosion {
    background: radial-gradient(circle, #fff, #00ff00, #0000ff, transparent);
    animation: ultramanExplosion 0.5s ease-out forwards;
}

@keyframes ultramanExplosion {
    to {
        transform: scale(3) rotate(360deg);
        opacity: 0;
    }
}

/* 炮弹 */
.bullet {
    position: absolute;
    width: var(--bullet-size);
    height: var(--bullet-size);
    background-color: #ff0;
    border-radius: 50%;
    box-shadow: 0 0 10px #ff0;
}

/* 爆炸效果 */
.explosion {
    position: absolute;
    width: var(--explosion-size);
    height: var(--explosion-size);
    background: radial-gradient(circle, #ff0, #f00, transparent);
    border-radius: 50%;
    animation: explode 0.5s ease-out forwards;
}

@keyframes explode {
    to {
        transform: scale(2);
        opacity: 0;
    }
}

/* 烟火效果 */
.firework {
    position: absolute;
    width: 4px;
    height: 4px;
    background-color: #fff;
    border-radius: 50%;
}

/* 题目区域 */
#questionArea {
    position: absolute;
    left: 50%;
    transform: translateX(-50%);
    text-align: center;
    background-color: #333;
    padding: 20px 40px;
    border: 2px solid #0f0;
    box-shadow: 0 0 20px #0f0;
    min-width: 400px;
    position: relative;
}

#question {
    font-size: 36px;
    color: #0f0;
    margin-bottom: 30px;
    text-shadow: 2px 2px 4px #000;
}

/* 快捷键提示 */
.keyboard-hint {
    position: absolute;
    bottom: 8px;
    right: 15px;
    font-size: 12px;
    color: #888;
    font-style: italic;
    background-color: rgba(0, 0, 0, 0.3);
    padding: 2px 6px;
    border-radius: 3px;
}

/* 答案选项 */
#answerOptions {
    display: flex;
    justify-content: center;
    gap: 20px;
    margin-top: 20px;
}

.answer-btn {
    font-size: 28px;
    padding: 15px 30px;
    background-color: #444;
    color: #0f0;
    border: 2px solid #0f0;
    cursor: pointer;
    font-family: 'Courier New', monospace;
    font-weight: bold;
    transition: all 0.2s;
    min-width: 120px;
    position: relative;
}

.answer-btn .btn-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 5px;
}

.answer-btn .key-hint {
    position: absolute;
    top: 5px;
    left: 8px;
    background-color: #0f0;
    color: #000;
    font-size: 14px;
    font-weight: bold;
    width: 20px;
    height: 20px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    line-height: 1;
}

.answer-btn .answer-text {
    font-size: 28px;
}

.answer-btn:hover {
    background-color: #0f0;
    color: #000;
    transform: scale(1.1);
    box-shadow: 0 0 15px #0f0;
}

.answer-btn:hover .key-hint {
    background-color: #000;
    color: #0f0;
}

.answer-btn:active {
    transform: scale(0.95);
}

/* 禁用状态的答案按钮 */
.answer-btn.disabled,
.answer-btn:disabled {
    background-color: #222;
    color: #666;
    border-color: #444;
    cursor: not-allowed;
    opacity: 0.5;
    transform: none !important;
    box-shadow: none;
}

.answer-btn.disabled .key-hint,
.answer-btn:disabled .key-hint {
    background-color: #444;
    color: #888;
}

.answer-btn.disabled:hover,
.answer-btn:disabled:hover {
    background-color: #222;
    color: #666;
    transform: none;
    box-shadow: none;
}

.answer-btn.disabled:hover .key-hint,
.answer-btn:disabled:hover .key-hint {
    background-color: #444;
    color: #888;
}

/* 倒计时 */
#timer {
    position: absolute;
    top: 20px;
    left: 50%;
    transform: translateX(-50%);
    font-size: 48px;
    color: #f00;
    text-shadow: 2px 2px 4px #000;
}



/* 失误榜 */
#mistakeCounter {
    position: absolute;
    top: 60px;
    right: 20px;
    font-size: 24px;
    color: #fff;
    background-color: #333;
    padding: 10px 20px;
    border: 2px solid #f00;
}

/* 得分显示 */
#scoreCounter {
    position: absolute;
    top: 60px;
    left: 140px;  /* 给暂停按钮留出空间 */
    font-size: 24px;
    color: #fff;
    background-color: #333;
    padding: 10px 20px;
    border: 2px solid #0f0;
}

/* 连击计数器 */
.combo-counter {
    position: absolute;
    right: 180px;
    top: 60px;
    font-size: 24px;
    color: #0ff;
    font-weight: bold;
    text-shadow: 2px 2px 4px #000;
    background-color: rgba(0, 0, 0, 0.7);
    padding: 10px 20px;
    border: 2px solid #0ff;
    border-radius: 10px;
    display: none;
}

.combo-counter.active {
    display: block;
    animation: comboPulse 0.5s ease-out;
}

@keyframes comboPulse {
    0% {
        transform: scale(1);
    }
    50% {
        transform: scale(1.2);
    }
    100% {
        transform: scale(1);
    }
}

/* 统计信息 */
#stats {
    position: absolute;
    bottom: 20px;
    left: 20px;
    font-size: 18px;
    color: #0f0;
}

/* 答案反馈效果 */
.correct-answer {
    animation: correctPulse 0.5s ease-out;
}

.wrong-answer {
    animation: wrongShake 0.5s ease-out;
}

@keyframes correctPulse {
    0% { background-color: #0f0; }
    100% { background-color: #444; }
}

@keyframes wrongShake {
    0%, 100% { transform: translateX(0); background-color: #f00; }
    20%, 60% { transform: translateX(-10px); }
    40%, 80% { transform: translateX(10px); }
}

/* 按钮倒计时提示 */
.button-countdown {
    font-size: 18px;
    color: #ff0;
    text-align: center;
    margin-top: 10px;
    font-weight: bold;
    text-shadow: 2px 2px 4px #000;
    animation: countdownPulse 0.5s ease-in-out infinite alternate;
}

@keyframes countdownPulse {
    0% { opacity: 0.7; transform: scale(1); }
    100% { opacity: 1; transform: scale(1.05); }
}

/* 暂停按钮 */
#pauseBtn {
    position: absolute;
    top: 60px;
    left: 20px;
    background-color: #0a0;
    color: #fff;
    border: 2px solid #0f0;
    padding: 10px 20px;
    font-size: 24px;
    font-weight: bold;
    cursor: pointer;
    font-family: 'Courier New', monospace;
    box-shadow: 0 0 10px #0f0;
    z-index: 150;  /* 确保显示在其他元素之上 */
}

#pauseBtn:hover {
    background-color: #080;
    transform: scale(1.05);
}

#pauseBtn.paused {
    background-color: #f00;
    border-color: #f00;
    box-shadow: 0 0 10px #f00;
}

/* 暂停遮罩 */
#pauseOverlay {
    display: none;
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: rgba(0, 0, 0, 0.7);
    z-index: 100;
}

#pauseOverlay .pause-text {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    font-size: 72px;
    color: #0f0;
    text-shadow: 4px 4px 8px #000;
    font-weight: bold;
}

/* 大呆豆闪现 */
.bigDummy {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    font-size: 72px;
    color: #f00;
    font-weight: bold;
    text-shadow: 4px 4px 8px #000;
    animation: flash 1s ease-out forwards;
    pointer-events: none;
}

@keyframes flash {
    0% {
        opacity: 0;
        transform: translate(-50%, -50%) scale(0.5);
    }
    50% {
        opacity: 1;
        transform: translate(-50%, -50%) scale(1.2);
    }
    100% {
        opacity: 0;
        transform: translate(-50%, -50%) scale(1);
    }
}

/* 快速答题奖励提示 */
.quick-bonus {
    position: absolute;
    left: 50%;
    top: 30%;
    transform: translateX(-50%);
    font-size: 48px;
    font-weight: bold;
    text-shadow: 3px 3px 6px #000;
    animation: quickBonus 1.5s ease-out forwards;
    pointer-events: none;
    z-index: 50;
}

.quick-bonus.streak-1 {
    color: #0f0;
}

.quick-bonus.streak-2 {
    color: rgb(253, 73, 73);
    font-size: 56px;
}

.quick-bonus.streak-3 {
    color: #ff0;
    font-size: 66px;
    animation: quickBonusSpecial 1.5s ease-out forwards;
}

@keyframes quickBonus {
    0% {
        opacity: 0;
        transform: translateX(-50%) translateY(20px) scale(0.5);
    }
    40% {
        opacity: 1;
        transform: translateX(-50%) translateY(-10px) scale(1.2);
    }
    100% {
        opacity: 0;
        transform: translateX(-50%) translateY(-40px) scale(1);
    }
}

@keyframes quickBonusSpecial {
    0% {
        opacity: 0;
        transform: translateX(-50%) translateY(20px) scale(0.5) rotate(0deg);
    }
    40% {
        opacity: 1;
        transform: translateX(-50%) translateY(-10px) scale(1.3) rotate(5deg);
    }
    60% {
        transform: translateX(-50%) translateY(-20px) scale(1.2) rotate(-5deg);
    }
    100% {
        opacity: 0;
        transform: translateX(-50%) translateY(-50px) scale(1) rotate(0deg);
    }
}

/* GameOver画面 */
#gameOverScreen {
    display: none;
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    background-color: #333;
    border: 3px solid #f00;
    padding: 30px 50px;
    text-align: center;
    box-shadow: 0 0 30px #f00;
    min-width: 400px;
    z-index: 200;
}

/* 子弹打字效果 */
@keyframes bulletType {
    0% {
        opacity: 0;
        transform: translateX(-50px) scale(0.5);
        color: #f00;
        text-shadow: 0 0 10px #f00;
    }
    50% {
        opacity: 1;
        transform: translateX(0) scale(1.2);
        color: #fff;
        text-shadow: 0 0 20px #fff, 0 0 30px #f00;
    }
    100% {
        opacity: 1;
        transform: translateX(0) scale(1);
        color: #f00;
        text-shadow: 3px 3px 6px #000;
    }
}

.bullet-char {
    display: inline-block;
    animation: bulletType 0.3s ease-out forwards;
    margin: 0 2px;
}

/* 统计信息打字效果 */
@keyframes statReveal {
    0% {
        opacity: 0;
        transform: translateY(20px);
    }
    100% {
        opacity: 1;
        transform: translateY(0);
    }
}

.stat-item {
    opacity: 0;
    animation: statReveal 0.5s ease-out forwards;
}

.stat-item:nth-child(1) { animation-delay: 0.5s; }
.stat-item:nth-child(2) { animation-delay: 0.7s; }
.stat-item:nth-child(3) { animation-delay: 0.9s; }
.stat-item:nth-child(4) { animation-delay: 1.1s; }

/* 慢题列表打字效果 */
.slow-questions {
    opacity: 0;
    animation: statReveal 0.5s ease-out forwards;
    animation-delay: 1.3s;
}

.slow-question-item {
    opacity: 0;
    animation: statReveal 0.4s ease-out forwards;
}

.slow-question-item:nth-child(1) { animation-delay: 1.5s; }
.slow-question-item:nth-child(2) { animation-delay: 1.7s; }
.slow-question-item:nth-child(3) { animation-delay: 1.9s; }

/* 答错题目列表打字效果 */
.wrong-questions {
    opacity: 0;
    animation: statReveal 0.5s ease-out forwards;
    animation-delay: 2.0s;
}

/* 重试按钮打字效果 */
#retryBtn {
    opacity: 0;
    animation: statReveal 0.5s ease-out forwards;
    animation-delay: 2.5s;
}

#gameOverScreen h2 {
    color: #f00;
    font-size: 48px;
    margin-bottom: 30px;
    text-shadow: 3px 3px 6px #000;
}

#gameOverScreen .stats-container {
    margin: 20px 70px 0 50px;
    text-align: left;
}

#gameOverScreen .stat-item {
    font-size: 20px;
    color: #fff;
    margin: 10px 0;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

#gameOverScreen .stat-label {
    color: #aaa;
}

#gameOverScreen .stat-value {
    color: #0f0;
    font-weight: bold;
}

#gameOverScreen .slow-questions {
    margin-top: 20px;
    border-top: 2px solid #666;
}

#gameOverScreen .slow-questions h3 {
    color: #ff0;
    font-size: 24px;
    margin-bottom: 15px;
}

#gameOverScreen .slow-question-item {
    font-size: 18px;
    color: #fff;
    margin: 8px 0;
    padding-left: 20px;
}

#gameOverScreen .slow-question-time {
    color: #f00;
    font-weight: bold;
}

/* 答错题目样式 */
#gameOverScreen .wrong-questions {
    margin-top: 20px;
    padding-top: 20px;
    border-top: 2px solid #666;
    max-height: 300px;
    overflow-y: auto;
}

#gameOverScreen .wrong-questions h3 {
    color: #f00;
    font-size: 24px;
    margin-bottom: 15px;
}

#gameOverScreen .wrong-question-item {
    font-size: 18px;
    color: #fff;
    margin: 8px 0;
    padding-left: 20px;
    opacity: 0;
    animation: statReveal 0.4s ease-out forwards;
}

#gameOverScreen .wrong-question-time {
    color: #ff0;
    font-weight: bold;
}

/* 答错题目的滚动条样式 */
#gameOverScreen .wrong-questions::-webkit-scrollbar {
    width: 8px;
}

#gameOverScreen .wrong-questions::-webkit-scrollbar-track {
    background: #222;
    border-radius: 4px;
}

#gameOverScreen .wrong-questions::-webkit-scrollbar-thumb {
    background: #666;
    border-radius: 4px;
}

#gameOverScreen .wrong-questions::-webkit-scrollbar-thumb:hover {
    background: #888;
}

#retryBtn {
    background-color: #0f0;
    color: #000;
    border: none;
    padding: 15px 30px;
    font-size: 24px;
    font-weight: bold;
    cursor: pointer;
    margin-top: 30px;
    box-shadow: 0 0 15px #0f0;
    font-family: 'Courier New', monospace;
}

#retryBtn:hover {
    background-color: #0a0;
    transform: scale(1.05);
}

/* 玩家坦克血条特殊样式 */
#playerTank .health-bar {
    bottom: 60px;  /* 显示在坦克上方 */
}

/* 敌方坦克受伤动画 */
.enemy-bullet {
    background-color: #f00;
    box-shadow: 0 0 10px #f00;
}

/* 倒计时进度条样式 */
#timerContainer {
    position: absolute;
    top: 0px;
    left: 50%;
    transform: translateX(-50%);
    width: 100%;
    height: 50px;
    background-color: #333;
    overflow: hidden;
    box-shadow: 0 0 20px rgba(0, 0, 0, 0.5);
}

#timerProgress {
    height: 100%;
    background: linear-gradient(90deg, #0f0, #ff0, #f00);
    width: 100%;
    transition: width 1s linear;
    position: relative;
}

#timerProgress::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.3), transparent);
    animation: shimmer 2s infinite;
}

@keyframes shimmer {
    0% { transform: translateX(-100%); }
    100% { transform: translateX(100%); }
}

#timerText {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    font-size: 32px;
    color: #fff;
    font-weight: bold;
    text-shadow: 2px 2px 4px #000;
    z-index: 10;
}

/* 全屏闪烁报警 */
#timeoutWarning {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background-color: rgba(255, 0, 0, 0.3);
    z-index: 1000;
    display: none;
    pointer-events: none;
}

#timeoutWarning.active {
    animation: warningFlash 0.5s ease-in-out infinite;
}

@keyframes warningFlash {
    0%, 100% {
        background-color: rgba(255, 0, 0, 0.1);
    }
    50% {
        background-color: rgba(255, 0, 0, 0.5);
    }
}

/* 最后3秒倒计时数字特效 */
.final-countdown {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    font-size: 120px;
    color: #f00;
    font-weight: bold;
    text-shadow: 0 0 30px #f00;
    z-index: 1001;
    animation: countdownPulse 1s ease-out forwards;
    pointer-events: none;
}

@keyframes countdownPulse {
    0% {
        opacity: 0;
        transform: translate(-50%, -50%) scale(0.5);
    }
    50% {
        opacity: 1;
        transform: translate(-50%, -50%) scale(1.2);
    }
    100% {
        opacity: 0;
        transform: translate(-50%, -50%) scale(1);
    }
}

/* 移动端适配 */
@media screen and (max-width: 768px) {
    /* 确保阻止缩放和滚动 */
    body {
        touch-action: manipulation;
        user-select: none;
        -webkit-user-select: none;
        -webkit-touch-callout: none;
        -webkit-tap-highlight-color: transparent;
    }

    /* 设置界面移动端适配 */
    #setupScreen {
        width: 95vw;
        max-width: none;
        min-width: auto;
        padding: 15px;
        font-size: 12px;
    }

    #setupScreen h1 {
        font-size: 20px;
        margin-bottom: 15px;
    }

    .option-group {
        margin: 15px 0;
        padding: 10px;
    }

    .radio-group {
        /* flex-direction: column; */
        gap: 8px;
    }

    .radio-item {
        margin-right: 0;
        margin-bottom: 5px;
    }

    .radio-item label {
        font-size: 12px;
    }

    .setup-option small {
        margin-left: 0 !important;
        margin-top: 5px;
        font-size: 10px;
    }

    #startBtn {
        padding: 12px 24px;
        font-size: 16px;
    }

    /* 游戏界面移动端适配 */
    #gameScreen {
        overflow: hidden;
    }

    /* 坦克位置调整 */
    #playerTank {
        left: 50px;
    }

    #enemyTank {
        right: 50px;
    }

    /* 血条调整 */
    .health-bar {
        height: 8px;
        top: -15px;
    }

    /* 敌方坦克等级显示调整 */
    .enemy-level {
        font-size: 14px;
        top: -32px;
    }

    /* 玩家昵称显示调整 */
    .player-nickname {
        font-size: 14px;
        top: -38px;
        white-space: nowrap;
        min-width: max-content;
    }

    /* 顶部控制栏调整 */
    #pauseBtn {
        left: 10px;
        padding: 8px 12px;
        font-size: 16px;
    }

    #scoreCounter {
        left: 100px;
        font-size: 16px;
        padding: 8px 15px;
    }

    #mistakeCounter {
        right: 10px;
        font-size: 16px;
        padding: 8px 15px;
    }

    /* 连击计数器调整 */
    #comboCounter {
        top: 50px;
        right: 110px;
        font-size: 20px;
        padding: 5px 10px;
    }


    /* 答案选项移动端适配 */
    #answerOptions {
        display: flex;
        gap: 12px;
        margin-top: 15px;
    }

    .answer-btn {
        font-size: 20px;
        padding: 15px 20px;
        min-width: auto;
        width: 100%;
        margin: 0;
        position: relative;
        touch-action: manipulation;
    }

    .answer-btn .key-hint {
        top: 8px;
        left: 12px;
        width: 24px;
        height: 24px;
        font-size: 12px;
    }

    .answer-btn .answer-text {
        font-size: 20px;
        margin-left: 30px;
    }

    /* 快捷键提示移动端调整 */
    .keyboard-hint {
        bottom: 5px;
        right: 10px;
        font-size: 10px;
    }

    /* 快速答题奖励提示调整 */
    .quick-bonus {
        font-size: 32px;
        top: 25%;
    }

    .quick-bonus.streak-2 {
        font-size: 40px;
    }

    .quick-bonus.streak-3 {
        font-size: 48px;
    }

    /* 大呆豆闪现调整 */
    .bigDummy {
        font-size: 48px;
    }

    /* 最后倒计时数字调整 */
    .final-countdown {
        font-size: 80px;
    }

    /* GameOver界面移动端适配 */
    #gameOverScreen {
        width: 95vw;
        max-width: 450px;
        padding: 20px;
        max-height: 80vh;
        overflow-y: auto;
    }

    #gameOverScreen h2 {
        font-size: 32px;
        margin-bottom: 20px;
    }

    #gameOverScreen .stats-container {
        margin: 15px 0;
        text-align: left;
    }

    #gameOverScreen .stat-item {
        font-size: 16px;
        margin: 8px 0;
    }

    #gameOverScreen .slow-questions h3,
    #gameOverScreen .wrong-questions h3 {
        font-size: 18px;
        margin-bottom: 10px;
    }

    #gameOverScreen .slow-question-item,
    #gameOverScreen .wrong-question-item {
        font-size: 14px;
        margin: 6px 0;
        padding-left: 15px;
    }

    #gameOverScreen .wrong-questions {
        max-height: 200px;
    }

    #retryBtn {
        padding: 12px 24px;
        font-size: 18px;
        margin-top: 20px;
    }

    /* 暂停界面调整 */
    #pauseOverlay .pause-text {
        font-size: 48px;
    }

    /* 炮弹大小调整 */
    .bullet {
        width: 6px;
        height: 6px;
    }

    /* 爆炸效果调整 */
    .explosion {
        width: 30px;
        height: 30px;
    }

    .big-explosion {
        width: 60px;
        height: 60px;
    }
}

/* 更小屏幕设备（宽度小于480px）额外优化 */
@media screen and (max-width: 480px) {
    #setupScreen {
        width: 95vw;
        padding: 15px;
    }

    #setupScreen h1 {
        font-size: 20px;
    }

    .setup-option label {
        font-size: 12px;
    }

    #startBtn {
        padding: 10px 20px;
        font-size: 14px;
    }

    .answer-btn {
        font-size: 16px;
        padding: 12px 15px;
    }

    .answer-btn .answer-text {
        font-size: 16px;
    }


    /* 进一步缩小坦克 */
    :root {
        --tank-width: 35px;
        --tank-height: 24px;
        --tank-total-height: 36px;
        --barrel-width: 24px;
        --barrel-height: 5px;
        --barrel-top-offset: 10px;
        --barrel-extend: 12px;
    }

    /* 玩家昵称显示调整 */
    .player-nickname {
        font-size: 12px;
        top: -30px;
        white-space: nowrap;
        min-width: max-content;
    }

    /* 敌方坦克等级显示调整 */
    .enemy-level {
        font-size: 12px;
        top: -30px;
    }
lo
    /* 移动端奥特曼模式适配 */
    .ultraman-mode #playerTank .tank-body::before,
    .ultraman-mode #playerTank .tank-body::after {
        font-size: 28px;
    }
    
    .ultraman-mode #enemyTank .tank-body::before {
        font-size: 28px;
    }
}

/* 横屏模式提醒 */
@media screen and (orientation: landscape) and (max-height: 500px) {
    body::before {
        content: "建议竖屏游戏以获得最佳体验";
        position: fixed;
        top: 10px;
        left: 50%;
        transform: translateX(-50%);
        background-color: rgba(255, 165, 0, 0.9);
        color: #000;
        padding: 5px 15px;
        border-radius: 15px;
        font-size: 12px;
        z-index: 9999;
        font-weight: bold;
    }
}