:root {
    --nav-bg: #333;
    --nav-fg: #fff;
    --nav-accent: #fff;
    --nav-max-width: 1200px;
}

.topnav {
    position: relative;
    z-index: 500;
    background: var(--nav-bg);
    color: var(--nav-fg);
    min-width: 320px;
}

.topnav__inner {
    display: grid;
    grid-template-columns: 1fr auto;
    align-items: center;
    gap: 1rem;
    padding: 1rem 1.5rem;
    max-width: var(--nav-max-width);
    margin: 0 auto;
}

.topnav__logo {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--nav-accent);
    text-decoration: none;
    display: inline-block;
    padding-left: 30px;
    position: relative;
    margin-left: 8px;
}

a.topnav__logo:before {
    content: url(/images/favicon.svg);
    position: absolute;
    top: -7px;
    left: -12px;
}

.topnav__toggle {
    display: none;
    font-size: 1.5rem;
    background: transparent;
    color: var(--nav-fg);
    border: none;
    cursor: pointer;
}

.topnav__links {
    list-style: none;
    display: flex;
    align-items: center;
    gap: 1rem;
    margin: 0;
    padding: 0;
}

.topnav__links a {
    color: var(--nav-fg);
    text-decoration: none;
}

.topnav__links a:hover {
    text-decoration: underline;
}

.link-disabled {
    opacity: 0.5;
    pointer-events: none;
    cursor: not-allowed;
}

/* Mobile menu sheet */
.topnav__sheet {
    position: fixed;
    right: 0;
    top: 56px;
    width: min(85vw, 250px);
    background: var(--nav-bg);
    color: var(--nav-fg);
    box-shadow: 0 0 2px rgba(0, 0, 0, .5);
    z-index: 1000;
    opacity: 0;
    transition: opacity .3s ease;
    display: none;
}

.topnav__sheet.open {
    display: block;
    opacity: 1;
}

.topnav__sheet.hidden {
    display: none;
}

.topnav__sheetHead {
    padding: .75rem 1rem;
}

.topnav__close {
    font-size: 1.25rem;
    background: transparent;
    color: var(--nav-fg);
    border: none;
    cursor: pointer;
    position: absolute;
    right: 18px;
    top: 18px;
}

.topnav__sheetLinks {
    list-style: none;
    padding: 1rem;
    margin: 0;
    display: grid;
    gap: 1rem;
}

.topnav__sheetLinks a {
    color: var(--nav-fg);
    text-decoration: none;
    padding: .5rem .25rem;
    border-radius: .5rem;
    font-size: larger;
}

.topnav__sheetLinks a:hover {
    background: rgba(255,255,255,.08);
}

@media (max-width: 550px) {
    .topnav__inner {
        grid-template-columns: 1fr auto;
    }

    .topnav__links {
        display: none;
    }

    .topnav__toggle {
        display: inline-block;
        justify-self: end;
        background-image: url('/icons/burger.svg');
        width: 22px;
        height: 18px;
    }
}