header nav {
    position: fixed;
    top: 0;
    z-index: 100;
    display: flex;
    width: 100%;
    font-size: 0;
    box-shadow: 0 2px 4px var(--secondary-shadow);
}



header nav ul::before {
    content: "";
    display: block;
    flex-grow: 0.15;
    max-width: 10%;
}
header nav ul {
    display: flex;
    flex-grow: 1;
    align-items: center;
    justify-content: space-between;

    padding: 0.5rem 0;
    background-color: var(--background-color);
}
header nav ul::after {
    content: "";
    display: block;
    flex-grow: 0.15;
    max-width: 10%;
}



header nav ul li {
    position: relative;
    padding: 0 0.4rem;
    margin: 0;
    list-style: none;
}
header nav ul li a:has(div.nav-logo) {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    user-select: none;
    transition: all 0.2s ease-in-out 0s;
    justify-content: left;
}
header nav ul li a div.nav-logo img {
    width: 5rem;
}
header nav ul li a span#logo-label {
    font-size: 1.2rem;
    font-weight: 700;
    color: var(--secondary-color);
    flex-wrap: wrap;
}
header nav ul li a div#logo-light {
    display: inline-block;
}
header nav ul li a div#logo-dark {
    display: none;
}
header nav ul li:has(div#nav-spacer) {
    flex-grow: 1;
    max-width: 50%;
}
header nav ul li a {
    color: var(--primary-color);
    font-size: 1rem;
    text-decoration: none;
    user-select: none;
    transition: all 0.2s ease-in-out 0s;
}
header nav ul li a:hover{
    color: var(--secondary-color);
}
header nav ul li a::after {
    content: "";
    position: absolute;
    display: block;
    left: 50%;
    top: 125%;
    border-radius: 10px;
    height: 0.2rem;
    width: 0;
    background-color: var(--secondary-color);
    transition: all 0.2s ease-in-out 0s;
}
header nav ul li a:hover::after {
    left: 25%;
    width: 50%;
}
header nav ul li a#main-page:hover::after{
    left:0 !important;
    width: 0 !important;
}

header nav ul li a[aria-current="page"] {
    color: var(--secondary-color);
}
header nav ul li a[aria-current="page"]::after {
    left: 25%;
    width: 50%;
}
header nav ul li button#theme-control {
    position: relative;
    display: flex;
    justify-content: center;
    align-items: center;
    width: 2.5rem;
    height: 2.5rem;
    margin-left: 0.5rem;
    border-radius: 9999rem;
    background-color: var(--secondary-color);
    color: var(--on-secondary-color);
    border: 0;
    overflow: hidden;
    transition: all 0.2s cubic-bezier(.45,.52,.12,.95) 0s;
}
header nav ul li button#theme-control:hover {
    background-color: var(--secondary-dark);
}
header nav ul li button#theme-control svg {
    position: absolute;
    width: 50%;
    height: 50%;
    transition: opacity 0.3s ease, transform 0.3s ease;
}
header nav ul li button#theme-control svg#sun {
    opacity: 1;
    transform: rotate(0deg) scale(1);
}
header nav ul li button#theme-control svg#moon {
    opacity: 0;
    transform: rotate(-90deg) scale(0.5);
}
html[data-theme="dark"] header nav ul li button#theme-control svg#sun {
    opacity: 0;
    transform: rotate(90deg) scale(0.5);
}
html[data-theme="dark"] header nav ul li button#theme-control svg#moon {
    opacity: 1;
    transform: rotate(0deg) scale(1);
}
@media (prefers-reduced-motion: reduce) {
    header nav ul li button#theme-control svg,
    header nav ul li.nav-item {
        transition: none;
    }
}

header nav ul li:has(button#nav-toggle) {
    display: none;
}
header nav ul li button#nav-toggle {
    display: flex;
    justify-content: center;
    align-items: center;
    width: 2.5rem;
    height: 2.5rem;
    margin-left: 0.5rem;
    border-radius: 9999rem;
    border: 0;
    background-color: var(--secondary-color);
    color: var(--on-secondary-color);
    transition: all 0.2s ease-in-out 0s;
}
header nav ul li button#nav-toggle:hover {
    background-color: var(--secondary-dark);
}
header nav ul li button#nav-toggle svg {
    width: 1.4rem;
    height: 1.4rem;
}

html[data-theme="dark"] header nav ul li a div#logo-light {
    display: none;
}
html[data-theme="dark"] header nav ul li a div#logo-dark {
    display: inline-block;
}

@media (width <= 800px) {
    header nav ul {
        flex-wrap: wrap;
        justify-content: flex-start;
        padding: 0.5rem 0.75rem;
    }
    header nav ul::before,
    header nav ul::after {
        flex-grow: 0;
        max-width: 0;
    }
    header nav ul li:has(div#nav-spacer) {
        display: block;
        order: 2;
        flex-grow: 1;
        max-width: none;
    }
    header nav ul li:first-child {
        order: 1;
        flex-grow: 0;
        min-width: 0;
    }
    header nav ul li:first-child a {
        min-width: 0;
    }
    header nav ul li:first-child a span#logo-label {
        flex-shrink: 1;
        white-space: nowrap;
        overflow: hidden;
        text-overflow: ellipsis;
    }
    header nav ul li:has(button#theme-control) {
        order: 3;
        flex-shrink: 0;
    }
    header nav ul li:has(button#nav-toggle) {
        order: 4;
        flex-shrink: 0;
        display: block;
    }
    header nav ul li.nav-item {
        order: 5;
        display: block;
        flex-basis: 100%;
        opacity: 0;
        max-height: 0;
        overflow: hidden;
        padding: 0;
        text-align: center;
        transition: opacity 0.25s ease, max-height 0.3s ease, padding 0.3s ease;
    }
    header nav ul li.nav-item a {
        display: inline-block;
        font-size: 1.1rem;
        padding: 0.6rem 1.4rem;
        border: 1px solid var(--background-hover);
        border-radius: 0.6rem;
    }
    header nav ul li.nav-item a:hover,
    header nav ul li.nav-item a[aria-current="page"] {
        background-color: var(--secondary-background);
        border-color: var(--secondary-color);
    }
    header nav ul li.nav-item a::after {
        display: none;
    }
    header nav.nav-open ul li.nav-item {
        opacity: 1;
        max-height: 4rem;
        padding: 0.9rem 0;
    }
    header nav.nav-open ul {
        box-shadow: 0 4px 16px var(--secondary-shadow);
    }
}

@media (width <= 480px) {
    header nav ul {
        padding-left: 0.25rem;
    }
    header nav ul li:first-child {
        padding-left: 0;
    }
    header nav ul li a div.nav-logo img {
        width: 3.5rem;
    }
    header nav ul li a span#logo-label {
        font-size: 0.95rem;
    }
    header nav ul li button#theme-control,
    header nav ul li button#nav-toggle {
        margin-left: 0.25rem;
    }
}