/**
 * ZINCAM/DEV — Header & Navigation Styles with Language & Theme Switchers
 */

.site-header {
    position: sticky;
    top: 0;
    left: 0;
    width: 100%;
    height: var(--header-height);
    z-index: 1000;
    background: var(--surface-glass);
    backdrop-filter: blur(14px);
    -webkit-backdrop-filter: blur(14px);
    border-bottom: 1px solid var(--border-subtle);
    transition: background-color var(--duration-normal) ease, border-color var(--duration-normal) ease;
}

.site-header.scrolled {
    background: var(--bg-primary);
    border-bottom-color: var(--border-medium);
}

.header-inner {
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1.5rem;
}

/* Brand Logo */
.brand-logo {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    font-family: var(--font-display);
    font-size: 1.25rem;
    font-weight: 800;
    letter-spacing: -0.01em;
    color: var(--text-primary);
    text-transform: uppercase;
}

.brand-logo .slash-dev {
    color: var(--signal-red);
    font-family: var(--font-mono);
    font-weight: 700;
    font-size: 1.1rem;
    letter-spacing: -0.02em;
}

.brand-meta {
    font-family: var(--font-mono);
    font-size: 0.625rem;
    color: var(--text-muted);
    letter-spacing: 0.12em;
    padding-left: 0.6rem;
    border-left: 1px solid var(--border-subtle);
}

/* Desktop Navigation */
.main-nav {
    display: flex;
    align-items: center;
    gap: 1.75rem;
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 1.5rem;
    list-style: none;
}

.nav-link {
    font-family: var(--font-mono);
    font-size: 0.75rem;
    letter-spacing: 0.08em;
    color: var(--text-secondary);
    text-transform: uppercase;
    position: relative;
    padding: 0.5rem 0;
    transition: color var(--duration-fast) ease;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 1.5px;
    background-color: var(--signal-red);
    transition: width var(--duration-normal) var(--ease-out-expo);
}

.nav-link:hover,
.nav-link.active {
    color: var(--text-primary);
}

.nav-link:hover::after,
.nav-link.active::after {
    width: 100%;
}

/* Header Utilities (Language & Theme) */
.header-utilities {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

/* Language Switcher */
.lang-switcher {
    display: flex;
    align-items: center;
    padding: 2px;
    background: var(--bg-secondary);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-pill);
    gap: 2px;
}

.lang-btn {
    background: transparent;
    border: none;
    padding: 0.25rem 0.55rem;
    font-family: var(--font-mono);
    font-size: 0.6875rem;
    font-weight: 600;
    color: var(--text-muted);
    border-radius: var(--radius-pill);
    cursor: pointer;
    transition: all var(--duration-fast) ease;
    text-transform: uppercase;
}

.lang-btn:hover {
    color: var(--text-primary);
}

.lang-btn.active {
    background: var(--signal-red);
    color: #ffffff;
}

/* Theme Toggle Button */
.theme-toggle-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.4rem;
    padding: 0.35rem 0.65rem;
    background: var(--bg-secondary);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-pill);
    color: var(--text-secondary);
    cursor: pointer;
    font-family: var(--font-mono);
    font-size: 0.6875rem;
    transition: all var(--duration-fast) ease;
}

.theme-toggle-btn:hover {
    border-color: var(--border-medium);
    color: var(--text-primary);
}

.theme-icon {
    font-size: 0.85rem;
    line-height: 1;
}

/* Header Status Pill */
.header-status {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-family: var(--font-mono);
    font-size: 0.6875rem;
    letter-spacing: 0.08em;
    color: var(--text-secondary);
    padding: 0.35rem 0.75rem;
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-pill);
    background: var(--bg-secondary);
}

/* Mobile Menu Toggle Button */
.mobile-toggle {
    display: none;
    background: var(--bg-secondary);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-sm);
    width: 40px;
    height: 40px;
    padding: 0;
    cursor: pointer;
    position: relative;
    color: var(--text-primary);
    align-items: center;
    justify-content: center;
}

.hamburger-line {
    display: block;
    width: 18px;
    height: 1.5px;
    background: var(--text-primary);
    position: absolute;
    transition: transform var(--duration-normal) var(--ease-out-expo), opacity var(--duration-fast) ease;
}

.hamburger-line:nth-child(1) { transform: translateY(-5px); }
.hamburger-line:nth-child(2) { transform: translateY(0); }
.hamburger-line:nth-child(3) { transform: translateY(5px); }

.mobile-toggle.active .hamburger-line:nth-child(1) { transform: rotate(45deg); }
.mobile-toggle.active .hamburger-line:nth-child(2) { opacity: 0; }
.mobile-toggle.active .hamburger-line:nth-child(3) { transform: rotate(-45deg); }

/* Mobile Menu Overlay Drawer */
.mobile-drawer {
    display: none;
}

@media (max-width: 1080px) {
    .brand-meta,
    .header-status {
        display: none;
    }
}

@media (max-width: 900px) {
    .nav-links,
    .header-utilities {
        display: none;
    }

    .mobile-toggle {
        display: flex;
    }

    .mobile-drawer {
        display: block;
        position: fixed;
        top: var(--header-height);
        left: 0;
        width: 100%;
        height: calc(100vh - var(--header-height));
        background: var(--bg-primary);
        backdrop-filter: blur(20px);
        padding: 2rem var(--container-padding);
        transform: translateY(-100%);
        opacity: 0;
        visibility: hidden;
        transition: transform var(--duration-smooth) var(--ease-out-expo), opacity var(--duration-normal) ease, visibility var(--duration-smooth);
        z-index: 999;
        overflow-y: auto;
        border-bottom: 1px solid var(--border-medium);
    }

    .mobile-drawer.open {
        transform: translateY(0);
        opacity: 1;
        visibility: visible;
    }

    .mobile-nav-list {
        list-style: none;
        display: flex;
        flex-direction: column;
        gap: 1.25rem;
        margin-bottom: 2rem;
    }

    .mobile-nav-link {
        font-family: var(--font-display);
        font-size: 1.85rem;
        font-weight: 700;
        color: var(--text-primary);
        text-transform: uppercase;
        display: flex;
        align-items: center;
        justify-content: space-between;
    }

    .mobile-nav-link.active {
        color: var(--signal-red);
    }

    .mobile-drawer-footer {
        padding-top: 1.5rem;
        border-top: 1px solid var(--border-subtle);
        display: flex;
        flex-direction: column;
        gap: 1.25rem;
    }

    .mobile-controls-row {
        display: flex;
        align-items: center;
        justify-content: space-between;
        gap: 1rem;
        padding-bottom: 1rem;
        border-bottom: 1px solid var(--border-subtle);
    }
}