/* ==========================================================
   THE AI ACE
   HEADER LAYOUT
========================================================== */

.site-header {
    position: sticky;
    top: 0;
    z-index: var(--z-header);

    width: 100%;
    min-height: var(--header-height);

    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 24px;

    padding: 0 24px;

    background: rgba(4, 11, 19, 0.94);
    border-bottom: 1px solid var(--border-color);

    backdrop-filter: blur(18px);
    -webkit-backdrop-filter: blur(18px);
}

/* ---------- BRAND ---------- */

.brand {
    display: inline-flex;
    align-items: center;
    gap: 12px;
    flex-shrink: 0;
}

.brand-mark {
    color: var(--color-primary);
    font-size: 2rem;
    font-weight: var(--fw-black);
    letter-spacing: -0.08em;
    line-height: 1;
}

.brand-copy {
    display: flex;
    flex-direction: column;
    gap: 1px;
}

.brand-copy strong {
    color: var(--text-primary);
    font-size: 1rem;
    font-weight: var(--fw-black);
    line-height: 1;
}

.brand-copy small {
    color: var(--text-muted);
    font-size: 0.58rem;
    font-weight: var(--fw-medium);
    letter-spacing: 0.09em;
    line-height: 1.2;
}

/* ---------- NAVIGATION ---------- */

.main-nav {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 24px;

    margin-left: auto;
    margin-right: auto;
}

.main-nav a {
    color: var(--text-secondary);
    font-size: 0.84rem;
    font-weight: var(--fw-semibold);
    white-space: nowrap;
}

.main-nav a:hover,
.main-nav a:focus-visible {
    color: var(--color-primary);
}

/* ---------- HEADER ACTIONS ---------- */

.header-actions {
    display: flex;
    align-items: center;
    gap: 10px;
    flex-shrink: 0;
}

/* ---------- LANGUAGE SELECTOR ---------- */

.language-selector {
    position: relative;
}

.language-button {
    min-height: 42px;

    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;

    padding: 9px 12px;

    color: var(--text-primary);
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
}

.language-button:hover,
.language-button:focus-visible {
    border-color: var(--color-accent);
}

.globe {
    color: var(--color-accent);
}

.language-current {
    font-size: 0.8rem;
    font-weight: var(--fw-bold);
}

.chevron {
    color: var(--text-muted);
    font-size: 0.75rem;
}

/* ---------- LANGUAGE MENU ---------- */

.language-menu {
    position: absolute;
    top: calc(100% + 10px);
    right: 0;

    min-width: 220px;
    padding: 10px;

    display: none;

    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-lg);
}

.language-menu.open {
    display: block;
}

.language-title {
    padding: 8px 10px 10px;

    color: var(--text-muted);
    font-size: var(--font-size-xs);
    font-weight: var(--fw-bold);
    text-transform: uppercase;
    letter-spacing: 0.08em;
}

.language-menu button {
    width: 100%;

    display: flex;
    align-items: center;
    gap: 10px;

    padding: 10px;

    color: var(--text-secondary);
    text-align: left;

    border-radius: var(--radius-sm);
}

.language-menu button:hover,
.language-menu button:focus-visible {
    color: var(--text-primary);
    background: rgba(255, 255, 255, 0.05);
}

/* ---------- THEME TOGGLE ---------- */

.theme-toggle,
.menu-toggle {
    width: 42px;
    height: 42px;

    display: inline-grid;
    place-items: center;

    color: var(--text-primary);
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
}

.theme-toggle:hover,
.menu-toggle:hover,
.theme-toggle:focus-visible,
.menu-toggle:focus-visible {
    border-color: var(--color-primary);
}

/* ---------- CTA ---------- */

.header-actions .btn-small {
    padding: 11px 16px;
    font-size: 0.76rem;
}

/* ---------- MOBILE MENU BUTTON ---------- */

.menu-toggle {
    display: none;
}

/* ---------- RESPONSIVE ---------- */

@media (max-width: 1180px) {
    .main-nav {
        gap: 16px;
    }

    .main-nav a {
        font-size: 0.78rem;
    }
}

@media (max-width: 980px) {
    .site-header {
        flex-wrap: wrap;
        padding: 10px 16px;
    }

    .menu-toggle {
        display: inline-grid;
    }

    .main-nav {
        order: 4;
        width: 100%;

        display: none;
        flex-direction: column;
        align-items: stretch;
        gap: 0;

        margin: 0;
        padding: 12px;

        background: var(--bg-card);
        border: 1px solid var(--border-color);
        border-radius: var(--radius-md);
    }

    .main-nav.open {
        display: flex;
    }

    .main-nav a {
        padding: 11px 12px;
        border-radius: var(--radius-sm);
    }

    .main-nav a:hover {
        background: rgba(255, 255, 255, 0.04);
    }
}

@media (max-width: 760px) {
    .brand-copy {
        display: none;
    }

    .header-actions {
        gap: 8px;
    }

    .header-actions .btn-small {
        display: none;
    }

    .language-button {
        padding: 9px 10px;
    }

    .language-current {
        display: none;
    }
}