#index-background-body {
    background-image: url('/assets/index-background.jpg');
    background-size: cover; /* 让背景图片完全覆盖元素 */
    background-position: center; /* 将背景图片定位到元素的中央 */
    background-attachment: fixed;
}

#index-main-container-div {
    display: flex; /* 将容器设置为 Flex 容器 */
    flex-direction: column;
    justify-content: center;
    align-items: center;
    width: 100vw;
    position: fixed;
    bottom: var(--index-main-container-bottom);
    left: 0px;
    color: white;
}

#index-main-text {
    font-size: var(--index-main-text-fontsize);
}


#index-emblem-div {
    background-image: url('/assets/index-emblem.png');
    background-size: contain; /* 让背景图片完全覆盖元素 */
    background-position: center; /* 将背景图片定位到元素的中央 */
    height: calc(1.2*(var(--index-main-text-fontsize)));
    width: calc(min(calc(3.96*1.2*(var(--index-main-text-fontsize))), 80vw));
} 

/* ********* button ******** */
#index-main-button {
    font-size: calc(var(--index-main-button-fontsize));
    background-color: white; /* 设置背景颜色为白色 */
    border: none;
    border-radius: calc(0.33*var(--index-main-button-fontsize)); /* 设置圆角半径 */
    width: calc(3.5 * var(--index-main-button-fontsize));
    height: calc(2 * var(--index-main-button-fontsize));
    margin-top: calc(1.5*var(--index-main-button-fontsize));
    overflow: hidden ;

    align-items: center;
    justify-content: center;

    
    .b::after {
      content: '';
      position: absolute;
      top: 0;
      left: 0;
      right: 0;
      bottom: 0;
      background-image: radial-gradient(circle, #ccc 10%, transparent 10.1%);
      transform: scale(10);
      opacity: 0;
      transition: all .6s;
    }
    .btn:active::after {
      transform: scale(0);
      opacity: .5;
      transition: 0s;
    }
}
/* ********--------********* */