@media screen and (max-width: 720px) {

    .header-nav > .active-nav {
        display: flex;
    }

    .header-content {
        position: relative;
    }
    .mobile-nav {
        position: relative;
        display: flex;
        width: 100px;
        height: 100px;
    }

    .mobile-nav > div,
    .mobile-nav > input {
        height: 100px;
        width: 100px;
        margin: 0;
        border: 0;
    }

    .cross-bar {
        position: absolute;
        top: 0;
        display: flex;
        flex-direction: column;
        justify-content: space-between;
        padding: 10px;
        z-index: 1;
    }

    .cross-bar > span {
        height: 20px;
        width: 80px;
        background: #3d0606;
        z-index: 5;
    }

    .mobile-nav > input {
        position: absolute;
        top: 0;
        cursor: pointer;
        z-index: 2;
        opacity: 0.1;
    }

    .header-nav > ul {
        display: none;
        position: absolute;
        left: 0;
        width: 100vw;
        background: #ff0000;
        flex-direction: column;
        height: calc(100vh - 100px);
    }
}