nav {
    position: sticky;
    margin: 0 auto;
    top: 0;
    /* 依照設計稿 1920 或 1000【兩者擇一】 */
    /* 不用的請【註解】  即可 */
    max-width: 1000px;
    z-index: 999;
}

.navbutton {
    position: absolute;
    width: 100%;
    height: 100%;
    top: 0%;
    display: flex;
}

.navbutton>li>a {
    display: block;
    height: 100%;
}

.navbutton>li:nth-child(1) {
    width: 15%;
    height: 100%;
    position: absolute;
    top: 0%;
    left: 28%;
}

.navbutton>li:nth-child(2) {
    width: 15%;
    height: 100%;
    position: absolute;
    top: 0%;
    left: 44%;
}

.navbutton>li:nth-child(3) {
    width: 21%;
    height: 100%;
    position: absolute;
    top: 0%;
    left: 60%;
}

.navbutton>li:nth-child(4) {
    width: 18%;
    height: 100%;
    position: absolute;
    top: 0%;
    left: 82%;
}