body {
    margin: 0;
    background: black;
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
}

.ruffle-wrapper {
    aspect-ratio: 4 / 3;   /* 핵심 */
    width: 80vw;           /* 화면에 맞게 조절 */
    max-width: 960px;      /* 선택 사항 */
    background: black;
}

#player {
    width: 100%;
    height: 100%;
}