* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: Verdana, Geneva, Tahoma, sans-serif;
}

img {
    max-width: 100%;
}

h1 {
    color: white;
    text-align: center;
    padding: 40px;
}

ul {
    list-style: none;
}

.page-header {
    background-color: black;
}

.preview {
    max-width: 1400px;
    margin-left: auto;
    margin-right: auto;
}

.preview video {
    background-color: black;
    width: 100%;
    border: 5px solid black;
    margin-top: 80px;
}

.screenshots {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    column-gap: 40px;
    row-gap: 40px;
    padding-top: 80px;
    padding-bottom: 80px;
}

.screenshot {
    max-width: 320px;
    min-width: 280px;
    border-radius: 20px;
    border: 5px solid black;
}

.screenshot img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    border-radius: 15px;
}

.game-wrapper {
    margin-left: auto;
    margin-right: auto;
    background-color: black;
    margin-bottom: 80px;
}

.webgl {
    outline: none;
}

.page-footer p {
    background-color: black;
    color: white;
    padding: 100px;
    text-align: center;
}

.score-display {
    position: fixed;
    top: 20px;
    left: 20px;
    color: white;
    font-size: 24px;
    z-index: 100;
    background: rgba(0,0,0,0.7);
    padding: 10px 20px;
    border-radius: 10px;
}

.game-info {
    position: fixed;
    top: 20px;
    right: 20px;
    z-index: 100;
    background: rgba(0,0,0,0.7);
    padding: 15px 25px;
    border-radius: 10px;
}

.time-display {
    color: #00ff00;
    font-size: 18px;
    margin-top: 8px;
}

.game-over {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    color: #ff0000;
    font-size: 48px;
    font-weight: bold;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.5);
    display: none;
}

.restart-btn {
    position: fixed;
    top: 60%;
    left: 50%;
    transform: translate(-50%, -50%);
    padding: 15px 30px;
    background: #00ff00;
    color: black;
    border-radius: 25px;
    cursor: pointer;
    font-size: 24px;
    font-weight: bold;
    display: none;
    z-index: 300;
    box-shadow: 0 0 15px rgba(0,255,0,0.5);
    transition: all 0.3s;
}

.restart-btn:hover {
    background: #00cc00;
    transform: translate(-50%, -50%) scale(1.1);
}

.start-btn {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    padding: 20px 40px;
    background: #00ff88;
    color: #000;
    font-size: 32px;
    border-radius: 40px;
    cursor: pointer;
    box-shadow: 0 0 20px rgba(0,255,136,0.5);
    transition: all 0.3s;
    z-index: 400;
    /* 确保按钮始终居中 */
    text-align: center;
}

.start-btn:hover {
    transform: translate(-50%, -50%) scale(1.1);
    background: #00cc70;
}

.restart-btn {
    /* 保持原有重启按钮样式 */
    top: 60%; /* 调整位置避免重叠 */
}