/* =========================================
   NAVIGATION (DESKTOP LANG SWITCHER + MOBILE)
   ========================================= */

/* Language Switcher */
.lang-switcher {
    position: fixed;
    top: 2rem;
    right: 2rem;
    z-index: 100;
    display: flex;
    gap: 0.5rem;
}

.lang-btn {
    width: 60px;
    height: 40px;
    background: var(--black);
    border: 2px solid var(--white);
    color: var(--white);
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 8px;
    overflow: hidden;
    padding: 0;
    transition: border-color var(--transition-base), transform var(--transition-base);
}

.lang-btn:hover {
    border-color: var(--accent);
    transform: scale(1.1);
}

.lang-btn img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.lang-btn[aria-current="true"] {
    display: none;
}

/* Mobile Header */
.mobile-header {
    display: none;
    position: fixed;
    top: 0; left: 0;
    width: 100%;
    padding: 1.5rem 2rem;
    z-index: 10000;
    justify-content: space-between;
    align-items: center;
    mix-blend-mode: difference;
    color: var(--white);
    border-bottom: 1px solid transparent;
    transition: background var(--transition-base),
                padding var(--transition-base),
                border-color var(--transition-base);
}

/* Jakmile se odscrolluje z hera, dostane hlavička vlastní podklad.
   `mix-blend-mode: difference` sice logo samo obarví podle toho, co je pod
   ním, ale nechává obsah projíždět těsně pod hlavičkou — text se pak s logem
   překrývá a ani jedno není čitelné. Na desktopu se nic nemění, tam je
   hlavička skrytá. */
.mobile-header.is-solid {
    mix-blend-mode: normal;
    background: rgba(10, 10, 10, 0.88);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom-color: rgba(255, 255, 255, 0.1);
    padding-top: 0.9rem;
    padding-bottom: 0.9rem;
}

.mobile-logo {
    display: block;
    line-height: 0;
}

.mobile-logo img {
    width: 62px;
    height: auto;
}

.hamburger-menu {
    width: 30px;
    height: 20px;
    position: relative;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    cursor: pointer;
    background: none;
    border: none;
    padding: 0;
}

.hamburger-menu span {
    display: block;
    width: 100%;
    height: 2px;
    background-color: var(--white);
    transition: transform var(--transition-base), opacity var(--transition-base);
}

.hamburger-menu.active span:nth-child(1) { transform: translateY(9px) rotate(45deg); }
.hamburger-menu.active span:nth-child(2) { opacity: 0; }
.hamburger-menu.active span:nth-child(3) { transform: translateY(-9px) rotate(-45deg); }

/* Mobile Nav Overlay */
.mobile-nav-overlay {
    position: fixed;
    top: 0; left: 0;
    width: 100%; height: 100vh;
    background: var(--black);
    z-index: 9999;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.4s ease;
}

.mobile-nav-overlay.active {
    opacity: 1;
    pointer-events: auto;
}

.mobile-nav-links {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 2rem;
}

.mobile-link {
    font-family: var(--font-heading);
    font-size: 3rem;
    font-weight: 800;
    color: var(--white);
    text-transform: uppercase;
    transition: color var(--transition-base);
    letter-spacing: -0.02em;
}

.mobile-link:hover {
    color: var(--accent);
}

.mobile-lang-switch {
    margin-top: 2rem;
    display: flex;
    gap: 2rem;
}

.m-lang-btn {
    font-family: var(--font-mono);
    font-size: 1.2rem;
    font-weight: 700;
    color: var(--gray);
    text-transform: uppercase;
    background: none;
    border: none;
    transition: color var(--transition-base);
}

.m-lang-btn:hover {
    color: var(--accent);
}

/* FAB — Floating Contact Button (mobile) */
.fab-contact {
    display: none;
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    width: 56px;
    height: 56px;
    background: var(--accent);
    border-radius: 50%;
    z-index: 9998;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    box-shadow: 0 4px 20px rgba(255, 51, 102, 0.4);
    transition: transform var(--transition-base), box-shadow var(--transition-base);
    color: var(--white);
    text-decoration: none;
    cursor: pointer !important;
}

.fab-contact:hover {
    transform: scale(1.1);
    box-shadow: 0 8px 30px rgba(255, 51, 102, 0.6);
}