.site-header {
    position: fixed;
    top: 0;
    left: 0;
    z-index: 50;
    width: 100%;
    padding: 12px 0;
    transition: padding 220ms ease, transform 220ms ease;
}

.site-header.is-scrolled {
    padding: 8px 0;
}

.header-shell {
    display: flex;
    align-items: center;
    justify-content: space-between;
    width: min(var(--max), calc(100% - 40px));
    min-height: 58px;
    margin: 0 auto;
    border: 1px solid var(--line);
    border-radius: 999px;
    padding: 0 10px 0 12px;
    background: rgba(255, 255, 255, 0.9);
    box-shadow: 0 18px 50px rgba(15, 23, 42, 0.08);
    backdrop-filter: blur(18px);
    transition: background 220ms ease, border-color 220ms ease, box-shadow 220ms ease;
}

.site-header.is-scrolled .header-shell,
.site-header.is-open .header-shell {
    border-color: var(--line);
    background: rgba(255, 255, 255, 0.94);
    box-shadow: var(--shadow);
    backdrop-filter: blur(18px);
}

.site-header .brand {
    display: inline-flex;
    align-items: center;
    min-width: 0;
    max-width: 220px;
    height: 46px;
    margin-left: 18px;
}

.site-header .brand-logo {
    display: block;
    width: auto;
    max-width: 100%;
    height: 42px;
    object-fit: contain;
    object-position: left center;
    transition: transform 220ms ease, opacity 220ms ease;
}

.site-header .brand:hover .brand-logo {
    opacity: 0.9;
    transform: translateY(-1px);
}

.site-nav {
    display: flex;
    align-items: center;
    gap: 4px;
}

.site-nav a {
    position: relative;
    border-radius: 14px;
    color: #5f6673;
    padding: 10px 15px;
    font-size: 0.9rem;
    font-weight: 750;
    isolation: isolate;
    overflow: hidden;
    transform: translateZ(0);
    transition: color 260ms ease, transform 260ms cubic-bezier(0.2, 0.8, 0.2, 1);
}

.site-nav a::before {
    position: absolute;
    inset: 0;
    z-index: -1;
    border-radius: inherit;
    background: #111827;
    content: "";
    opacity: 0;
    transform: translateY(132%) skewY(-7deg);
    transform-origin: left bottom;
    transition: opacity 160ms ease, transform 320ms cubic-bezier(0.2, 0.9, 0.2, 1);
}

.site-nav a::after {
    position: absolute;
    inset: 0;
    z-index: -1;
    border-radius: inherit;
    background: linear-gradient(110deg, transparent 0%, rgba(255, 255, 255, 0.18) 48%, transparent 56%);
    content: "";
    opacity: 0;
    transform: translateX(-110%);
    transition: opacity 180ms ease, transform 520ms cubic-bezier(0.2, 0.8, 0.2, 1);
}

.site-nav a:hover,
.site-nav a.is-active {
    color: #fff;
    transform: translateY(-2px);
}

.site-nav a:hover::before,
.site-nav a.is-active::before {
    opacity: 1;
    transform: translateY(0) skewY(0);
}

.site-nav a:hover::after,
.site-nav a.is-active::after {
    opacity: 1;
    transform: translateX(110%);
}

.language-switcher {
    position: relative;
    margin-left: 8px;
}

.language-switcher button {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 7px;
    min-width: 68px;
    height: 40px;
    border: 1px solid rgba(15, 23, 42, 0.1);
    border-radius: 14px;
    background: #fff;
    color: #111827;
    cursor: pointer;
    font: inherit;
    font-size: 0.82rem;
    font-weight: 850;
    box-shadow: 0 10px 26px rgba(15, 23, 42, 0.07);
    transition: transform 180ms ease, border-color 180ms ease, box-shadow 180ms ease;
}

.language-switcher button > span:first-child {
    line-height: 1;
}

.language-chevron {
    display: block;
    width: 7px;
    height: 7px;
    border-right: 2px solid currentColor;
    border-bottom: 2px solid currentColor;
    margin-top: -3px;
    transform: rotate(45deg);
}

.language-switcher button:hover,
.language-switcher.is-open button {
    border-color: rgba(17, 24, 39, 0.18);
    box-shadow: 0 14px 34px rgba(15, 23, 42, 0.12);
    transform: translateY(-1px);
}

.language-menu {
    position: absolute;
    top: calc(100% + 8px);
    right: 0;
    display: grid;
    min-width: 112px;
    gap: 4px;
    border: 1px solid rgba(15, 23, 42, 0.1);
    border-radius: 16px;
    background: rgba(255, 255, 255, 0.98);
    box-shadow: 0 20px 44px rgba(15, 23, 42, 0.14);
    padding: 6px;
    opacity: 0;
    pointer-events: none;
    transform: translateY(-6px);
    transition: opacity 160ms ease, transform 160ms ease;
}

.language-switcher.is-open .language-menu {
    opacity: 1;
    pointer-events: auto;
    transform: translateY(0);
}

.language-menu a {
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 36px;
    border-radius: 12px;
    color: #5f6673;
    font-size: 0.82rem;
    font-weight: 850;
}

.language-menu a:hover,
.language-menu a.is-active {
    background: #111827;
    color: #fff;
    transform: none;
}

.language-menu a::before,
.language-menu a::after {
    content: none;
}

.nav-toggle {
    display: none;
    width: 42px;
    height: 42px;
    border: 1px solid var(--line);
    border-radius: 8px;
    background: #fff;
    color: var(--text);
    cursor: pointer;
}

.nav-toggle-line {
    display: block;
    width: 18px;
    height: 2px;
    margin: 4px auto;
    border-radius: 99px;
    background: currentColor;
    transition: transform 180ms ease, opacity 180ms ease;
}

.nav-toggle.is-active .nav-toggle-line:nth-child(1) {
    transform: translateY(6px) rotate(45deg);
}

.nav-toggle.is-active .nav-toggle-line:nth-child(2) {
    opacity: 0;
}

.nav-toggle.is-active .nav-toggle-line:nth-child(3) {
    transform: translateY(-6px) rotate(-45deg);
}

@media (max-width: 820px) {
    .header-shell {
        width: min(100% - 28px, var(--max));
    }

    .nav-toggle {
        display: block;
    }

    .site-nav {
        position: fixed;
        top: 82px;
        right: 14px;
        left: 14px;
        display: grid;
        gap: 8px;
        padding: 12px;
        border: 1px solid var(--line);
        border-radius: 18px;
        background: rgba(255, 255, 255, 0.96);
        box-shadow: var(--shadow);
        backdrop-filter: blur(18px);
        opacity: 0;
        pointer-events: none;
        transform: translateY(-10px);
        transition: opacity 180ms ease, transform 180ms ease;
    }

    .site-nav.is-open {
        opacity: 1;
        pointer-events: auto;
        transform: translateY(0);
    }

    .site-nav a {
        padding: 14px;
    }

    .language-switcher {
        margin: 4px 0 0;
    }

    .language-switcher button {
        width: 100%;
        justify-content: space-between;
        height: 48px;
        padding: 0 14px;
    }

    .language-menu {
        position: static;
        grid-template-columns: repeat(3, minmax(0, 1fr));
        margin-top: 8px;
        opacity: 1;
        pointer-events: auto;
        transform: none;
        box-shadow: none;
    }

    .language-switcher:not(.is-open) .language-menu {
        display: none;
    }

    .site-header .brand {
        max-width: 176px;
        margin-left: 10px;
    }

    .site-header .brand-logo {
        height: 38px;
    }

}