/* ============================================================
   NAVBAR — horizontal on desktop, drawer on mobile
   ============================================================ */

.site-nav {
    position: sticky;
    top: 0;
    z-index: var(--z-nav);
    background: var(--nav-bg);
    backdrop-filter: blur(14px);
    -webkit-backdrop-filter: blur(14px);
    border-bottom: var(--border-width) solid var(--nav-border);
    /* The bar carries its own colour scheme in both themes, so its contents
       use the --nav-* tokens rather than the page text colours. */
    color: var(--nav-text);
    box-shadow: var(--shadow-md);
}

/* A hairline of moonlight along the bottom edge. */
.site-nav::after {
    content: "";
    position: absolute;
    left: 0;
    right: 0;
    bottom: -1px;
    height: 1px;
    background: linear-gradient(
        90deg,
        transparent,
        color-mix(in srgb, var(--gold) 55%, transparent),
        transparent
    );
    pointer-events: none;
}

.site-nav__inner {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    min-height: var(--nav-height-mobile);
}

@media (min-width: 768px) {
    .site-nav__inner {
        min-height: var(--nav-height);
        gap: var(--space-5);
    }
}

/* --- Brand ------------------------------------------------- */

.site-nav__brand {
    display: inline-flex;
    align-items: center;
    gap: var(--space-2);
    font-family: var(--font-display);
    font-size: var(--text-xl);
    font-weight: var(--weight-bold);
    letter-spacing: var(--tracking-wide);
    color: var(--nav-text-strong);
    text-decoration: none;
    margin-right: auto;
}

.site-nav__brand:hover {
    color: var(--nav-text-strong);
}

.site-nav__logo {
    width: 36px;
    height: 36px;
    border-radius: var(--radius-pill);
    transition: filter var(--duration-base) var(--ease-out);
}

.site-nav__brand:hover .site-nav__logo {
    filter: drop-shadow(var(--glow-moon));
}

/* --- Links ------------------------------------------------- */

.site-nav__links {
    display: flex;
    align-items: center;
    gap: var(--space-1);
    list-style: none;
    padding: 0;
}

.site-nav__link {
    position: relative;
    display: block;
    padding: var(--space-2) var(--space-3);
    font-size: var(--text-sm);
    font-weight: var(--weight-medium);
    color: var(--nav-text);
    text-decoration: none;
    border-radius: var(--radius-md);
    white-space: nowrap;
    transition: color var(--duration-fast) var(--ease-out),
                background-color var(--duration-fast) var(--ease-out);
}

.site-nav__link:hover {
    color: var(--nav-text-strong);
    background: var(--nav-hover);
}

.site-nav__link[aria-current="page"] {
    color: var(--nav-text-strong);
    font-weight: var(--weight-semibold);
}

.site-nav__link[aria-current="page"]::after {
    content: "";
    position: absolute;
    left: var(--space-3);
    right: var(--space-3);
    bottom: 2px;
    height: 2px;
    background: linear-gradient(90deg, transparent, var(--gold), transparent);
    border-radius: var(--radius-pill);
}

/* --- Actions ----------------------------------------------- */

.site-nav__actions {
    display: flex;
    align-items: center;
    gap: var(--space-2);
}

/* --- Mobile toggle ----------------------------------------- */

.site-nav__toggle {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 44px;
    height: 44px;
    /* It sits on the navbar background, so it takes the --nav-* tokens
       rather than the page surface colours. */
    color: var(--nav-text);
    border-radius: var(--radius-md);
    border: var(--border-width) solid color-mix(in srgb, var(--nav-text) 28%, transparent);
}

.site-nav__toggle:hover {
    color: var(--nav-text-strong);
    background: var(--nav-hover);
}

.site-nav__toggle .material-symbols-rounded {
    font-size: 1.5rem;
}

/* The two icons swap based on the expanded state. */
.site-nav__toggle .icon-close,
.site-nav__toggle[aria-expanded="true"] .icon-open {
    display: none;
}

.site-nav__toggle[aria-expanded="true"] .icon-close {
    display: inline-flex;
}

/* --- Responsive behaviour ----------------------------------
   Below 768px the links collapse into a drawer under the bar.
   ----------------------------------------------------------- */

@media (max-width: 767px) {
    .site-nav__menu {
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        display: grid;
        grid-template-rows: 0fr;
        background: var(--bg-surface);
        border-bottom: var(--border-width) solid var(--border);
        box-shadow: var(--shadow-lg);
        transition: grid-template-rows var(--duration-base) var(--ease-out);
    }

    .site-nav__menu[data-open="true"] {
        grid-template-rows: 1fr;
    }

    .site-nav__menu-inner {
        overflow: hidden;
        min-height: 0;
    }

    .site-nav__links {
        flex-direction: column;
        align-items: stretch;
        gap: 0;
        padding: var(--space-2) var(--page-gutter) var(--space-4);
    }

    .site-nav__link {
        padding: var(--space-3) var(--space-2);
        font-size: var(--text-base);
        border-radius: var(--radius-md);
        /* Comfortable tap target. */
        min-height: 48px;
        display: flex;
        align-items: center;
    }

    .site-nav__link[aria-current="page"]::after {
        left: var(--space-2);
        right: auto;
        width: 24px;
        bottom: var(--space-2);
    }
}

@media (min-width: 768px) {
    .site-nav__toggle {
        display: none;
    }

    .site-nav__menu,
    .site-nav__menu-inner {
        display: contents;
    }
}

/* ------------------------------------------------------------
   CONTROLS INSIDE THE BAR
   They sit on the navbar's own background, so they take the
   --nav-* tokens instead of the page surface colours.
   ------------------------------------------------------------ */

.site-nav .btn-icon,
.site-nav .lang-switch {
    color: var(--nav-text);
    background-color: transparent;
    border-color: color-mix(in srgb, var(--nav-text) 28%, transparent);
}

.site-nav .btn-icon:hover {
    color: var(--nav-text-strong);
    background-color: var(--nav-hover);
    border-color: color-mix(in srgb, var(--nav-text) 48%, transparent);
}

/* The mobile drawer sits below the bar and belongs to the page. */
@media (max-width: 767px) {
    .site-nav__menu {
        color: var(--text-primary);
    }

    .site-nav__menu .site-nav__link {
        color: var(--text-secondary);
    }

    .site-nav__menu .site-nav__link:hover,
    .site-nav__menu .site-nav__link[aria-current="page"] {
        color: var(--text-primary);
        background: var(--bg-surface-hover);
    }
}