/* 清除默认边距 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    /* 让flex布局生效 */
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    font-size: 2em;
    /* 隐藏滚动条 */
    overflow: hidden;
    background-color: #000;
}

/* VR场景全屏显示 */
a-scene {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
}