.site-header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: var(--color-header-bg);
    box-shadow: 0 1px 0 var(--color-border);
    height: var(--header-height);
    transition: background-color 0.25s ease;
}

.site-header::before {
    /* The blur lives on a pseudo-element: backdrop-filter on the header itself would make it the
       containing block of the fixed-position mobile offcanvas and collapse the menu to 72px. */
    content: "";
    position: absolute;
    inset: 0;
    z-index: -1;
    backdrop-filter: blur(8px);
    pointer-events: none;
}

.site-header .navbar {
    height: var(--header-height);
    padding: 0;
}

.site-header .navbar > .container {
    display: flex;
    flex-wrap: nowrap;
    align-items: center;
    justify-content: space-between;
    height: 100%;
}

.navbar-brand {
    display: flex;
    align-items: center;
    text-decoration: none;
    color: inherit;
    min-width: 0;
    margin-right: 0.75rem;
}

.navbar-brand:hover {
    color: inherit;
}

.navbar-toggler {
    flex-shrink: 0;
    margin-left: auto;
}

.nav-link {
    font-weight: 500;
    font-size: 0.9rem;
    color: var(--color-text) !important;
    padding: 0.5rem 0.85rem !important;
    transition: color 0.2s;
}

.nav-link:hover,
.nav-link.active {
    color: var(--color-nav-active) !important;
}

.nav-link:focus-visible,
.navbar-brand:focus-visible,
.navbar-toggler:focus-visible {
    outline: 3px solid var(--color-focus);
    outline-offset: 2px;
    box-shadow: none;
}

.nav-link.active {
    font-weight: 600;
}

[data-theme="dark"] .navbar-toggler {
    border-color: var(--color-border-strong);
}

[data-theme="dark"] .navbar-toggler-icon {
    filter: invert(1);
}

@media (max-width: 991.98px) {
    .site-header .brand-logo__tagline {
        display: none;
    }

    #mainNavOffcanvas {
        width: min(88vw, 320px);
        background: var(--color-surface);
        border-left: 1px solid var(--color-border);
    }

    #mainNavOffcanvas .offcanvas-header {
        padding: 1rem 1.25rem;
        border-bottom: 1px solid var(--color-border);
    }

    #mainNavOffcanvas .offcanvas-title {
        font-family: var(--font-display);
        font-size: 1.05rem;
        font-weight: 700;
        color: var(--color-heading);
    }

    #mainNavOffcanvas .offcanvas-body {
        padding: 0.75rem 1rem 1.25rem;
    }

    #mainNavOffcanvas .navbar-nav {
        width: 100%;
        gap: 0.15rem;
    }

    #mainNavOffcanvas .nav-link {
        padding: 0.75rem 0.85rem !important;
        border-radius: var(--radius-md);
    }

    #mainNavOffcanvas .nav-link:hover,
    #mainNavOffcanvas .nav-link.active {
        background: var(--color-control-bg);
    }

    #mainNavOffcanvas .nav-item.ms-lg-2 {
        margin-left: 0 !important;
        margin-top: 0.5rem;
    }

    #mainNavOffcanvas .btn-emerald {
        width: 100%;
        justify-content: center;
    }

    #mainNavOffcanvas {
        color: var(--color-text);
    }

    #mainNavOffcanvas .btn-close {
        opacity: 0.85;
    }

    #mainNavOffcanvas .btn-close:hover {
        opacity: 1;
    }

    #mainNavOffcanvas .btn-close:focus-visible {
        box-shadow: none;
        outline: 3px solid var(--color-focus);
        outline-offset: 2px;
    }
}

@media (max-width: 991.98px) {
    .navbar-toggler {
        min-width: 48px;
        min-height: 48px;
        display: inline-flex;
        align-items: center;
        justify-content: center;
    }

    #mainNavOffcanvas .btn-close {
        width: 44px;
        height: 44px;
        padding: 0;
        margin: 0 -0.5rem 0 auto;
        background-size: 1rem;
    }

    #mainNavOffcanvas .offcanvas-body {
        overflow-y: auto;
        overscroll-behavior: contain;
        padding-bottom: max(1.25rem, env(safe-area-inset-bottom));
    }

    #mainNavOffcanvas .nav-link {
        font-size: 1rem;
        min-height: 48px;
        display: flex;
        align-items: center;
    }
}

[data-theme="dark"] #mainNavOffcanvas .btn-close {
    filter: invert(1) grayscale(1) brightness(2);
}