.header-mega-menu{
    position: absolute;
    width: 100%;
    left: 0;
    top: 100%;
    opacity: 0;
    visibility: hidden;
    pointer-events: none;
    padding-inline: var(--page-padding);
    height: 100%;
}
.header-mega-menu::before{
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    display: block;
    width: 100%;
    height:100vh;
    background-color: rgba(0,0,0,0.75);
    z-index: -1;
    pointer-events: none;
}

.header-mega-menu::after{
    content: '';
    position:absolute;
    top: -100%;
    left: 0;
    display: block;
    width: 100%;
    height:100%;
    z-index: 2;
}
.header-mega-menu-body{
    position: relative;
    z-index: 1;
    display: grid;
    grid-template-columns: repeat(4,1fr);
    gap: 20px;
    background-color: rgba(var(--color-background));
    padding-block: 100px;
    border-top: 1px solid rgba(48, 41, 56, 0.20);
    border-radius: 20px;
}
.header-nav__menu-item:hover .header-mega-menu,
.header-mega-menu:hover {
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
}




.mega-menu-item .mega-menu-text {
    position: relative;
    display: inline-block;
    text-decoration: none;
}

.mega-menu-item .mega-menu-text::after {
    content: "";
    position: absolute;
    left: 0;
    bottom: -2px; /* 控制下划线位置 */
    width: 100%;
    height: 1px; /* 下划线粗细 */
    background-color: currentColor;

    transform: scaleX(0);
    transform-origin: left;
    transition: transform 0.3s ease;
}

.mega-menu-item:hover .mega-menu-text::after {
    transform: scaleX(1);
}

.header-nav__button:hover .header-nav__button-text {
    color: #0D37E2;
}