/* ... (您之前已有的通用 CSS 代码，如 body, header, hero, features, footer, animations) ... */
body {
    font-family: 'Arial', sans-serif;
    margin: 0;
    padding: 0;
    background-color: #121212;
    color: #e0e0e0;
    line-height: 1.6;
}

header {
    background: linear-gradient(90deg, #3a1c71, #d76d77, #ffaf7b);
    color: #fff;
    padding: 1.5rem 0;
    text-align: center;
    box-shadow: 0 4px 8px rgba(0,0,0,0.3);
    position: sticky;
    top: 0;
    z-index: 1000;
}

header h1 {
    margin: 0;
    font-size: 2.8rem;
    letter-spacing: 2px;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.5);
}

nav {
    margin-top: 1rem;
}

nav a {
    color: #fff;
    margin: 0 12px;
    text-decoration: none;
    font-size: 1.1rem;
    transition: color 0.3s ease, transform 0.3s ease;
}

nav a:hover {
    color: #ffaf7b;
    transform: scale(1.1);
}

.hero {
    padding: 8rem 2rem 5rem;
    text-align: center;
    background: url('https://images.unsplash.com/photo-1507525428034-b723cf961d3e?q=80&w=2070&auto=format&fit=crop') no-repeat center center/cover;
    color: #fff;
    position: relative;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: rgba(0,0,0,0.5);
}

.hero h2, .hero p, .hero button {
    position: relative;
    z-index: 1;
}

.hero h2 {
    font-size: 3.5rem;
    margin-bottom: 1rem;
    animation: fadeInDown 1s ease-out;
}

.hero p {
    font-size: 1.3rem;
    margin-bottom: 2.5rem;
    animation: fadeInUp 1s ease-out 0.5s;
    animation-fill-mode: backwards;
}

.hero button#ctaButton { /* Be specific if there are multiple buttons */
    background-color: #ffaf7b;
    color: #3a1c71;
    border: none;
    padding: 1rem 2.5rem;
    font-size: 1.2rem;
    font-weight: bold;
    cursor: pointer;
    border-radius: 50px;
    transition: background-color 0.3s ease, transform 0.3s ease;
    box-shadow: 0 4px 15px rgba(255, 175, 123, 0.4);
    animation: pulse 2s infinite;
}

.hero button#ctaButton:hover {
    background-color: #d76d77;
    transform: translateY(-3px) scale(1.05);
}

.features {
    padding: 3rem 2rem;
    text-align: center;
    display: flex;
    justify-content: space-around;
    flex-wrap: wrap;
}

.feature-item {
    background-color: #1f1f1f;
    padding: 2rem;
    margin: 1rem;
    border-radius: 10px;
    width: calc(33.333% - 4rem);
    min-width: 280px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.2);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.feature-item:hover {
    transform: translateY(-10px);
    box-shadow: 0 10px 20px rgba(0,0,0,0.3);
}

.feature-item img {
    margin-bottom: 1rem;
    border-radius: 5px;
}

.feature-item h4 {
    font-size: 1.5rem;
    color: #ffaf7b;
    margin-bottom: 0.5rem;
}

/* 俄罗斯方块游戏区域样式 */
.tetris-game {
    background-color: #222; /* 稍暗的背景 */
    padding: 2rem;
    margin: 3rem auto;
    max-width: 380px; /* 适应Canvas宽度和一些边距 */
    border-radius: 15px;
    text-align: center;
    box-shadow: 0 10px 30px rgba(0,0,0,0.5);
    border-top: 5px solid #00bcd4; /* 青色，科技感 */
}

.tetris-game h3 {
    color: #00bcd4; /* 匹配边框颜色 */
    font-size: 2.4rem; /* 稍大一点 */
    margin-bottom: 1.5rem;
    text-transform: uppercase; /* 大写标题 */
    letter-spacing: 1px;
}

.game-board-container {
    display: inline-block; /* 使容器包裹Canvas */
    border: 5px solid #333; /* 游戏区域边框 */
    box-shadow: inset 0 0 10px rgba(0,0,0,0.5); /* 内阴影增加深度感 */
    margin-bottom: 1.5rem;
}

#tetrisCanvas {
    display: block; /* 移除多余的底部空间 */
    background-color: #0d0d0d; /* 非常暗的游戏背景 */
}

.game-info {
    display: flex;
    justify-content: space-around; /* 分散对齐 */
    align-items: center;
    margin-bottom: 1.5rem;
    font-size: 1.2rem; /* 稍大字体 */
    color: #ccc;
    background-color: #2a2a2a; /* 信息区域背景 */
    padding: 0.8rem;
    border-radius: 8px;
}

.game-info p {
    margin: 0;
}

.game-info span { /* 分数和行数的数字样式 */
    color: #00bcd4;
    font-weight: bold;
}

button#startGameButton { /* 特定ID以避免与其他按钮冲突 */
    background: linear-gradient(45deg, #00bcd4, #007bff); /* 渐变按钮 */
    color: white;
    border: none;
    padding: 0.8rem 2rem;
    font-size: 1.1rem;
    font-weight: bold;
    cursor: pointer;
    border-radius: 8px;
    transition: all 0.3s ease;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    box-shadow: 0 4px 10px rgba(0, 188, 212, 0.3);
}

button#startGameButton:hover {
    transform: translateY(-2px) scale(1.05);
    box-shadow: 0 6px 15px rgba(0, 188, 212, 0.5);
}

.tetris-instructions {
    font-size: 0.9rem;
    color: #888; /* 更柔和的提示颜色 */
    margin-top: 1.5rem;
    padding: 0.8rem;
    background-color: rgba(0,0,0,0.2);
    border-radius: 5px;
}

footer {
    text-align: center;
    padding: 2rem;
    background-color: #0a0a0a;
    color: #777;
    margin-top: 3rem;
    font-size: 0.9rem;
}

/* 动画 (保持不变) */
@keyframes fadeInDown { /* ... */ }
@keyframes fadeInUp { /* ... */ }
@keyframes pulse { /* ... */ }