.site-header {
    background: var(--surface);
    border-bottom: 1px solid var(--border);
    padding: 1rem 2rem;
    position: sticky;
    top: 0;
    z-index: 1000;
}

.site-header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.site-header .logo {
    display: inline-flex;
    align-items: center;
    gap: 0.6rem;
    line-height: 1;
    position: relative;
    z-index: 2;
}

.site-header .logo-image {
    width: 50px;
    height: 50px;
    object-fit: contain;
    display: block;
    border-radius: 18px;
    margin-top: -28px;
    margin-bottom: -28px;
}

.site-header .logo-text {
    font-size: 1.35rem;
    font-weight: 800;
    color: var(--text-color);
    letter-spacing: 0.06em;
}

.site-header .logo:hover {
    color: inherit;
}

.site-header .logo::after {
    display: none;
}

.site-header .nav-toggle {
    display: none;
    border: 1px solid var(--border);
    background: var(--surface);
    color: var(--text-color);
    border-radius: 8px;
    padding: 0.35rem 0.6rem;
    font-size: 1.2rem;
    line-height: 1;
    cursor: pointer;
}

.site-header #site-nav {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.site-header a {
    color: var(--text-gray);
    text-decoration: none;
    font-weight: 500;
    font-size: 0.95rem;
    transition: color 0.3s ease;
    position: relative;
}

.site-header a:hover {
    color: var(--accent-blue);
}

.site-header a::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--accent-blue);
    transition: width 0.3s ease;
}

.site-header a:hover::after {
    width: 100%;
}

@media (max-width: 768px) {
    .site-header {
        padding: 0.8rem 1rem;
    }

    .site-header .container {
        flex-wrap: wrap;
        gap: 0.75rem;
    }

    .site-header .logo {
        max-width: calc(100% - 56px);
    }

    .site-header .logo-image {
        width: 50px;
        height: 50px;
        margin-top: -28px;
        margin-bottom: -28px;
    }

    .site-header .logo-text {
        font-size: 1.35rem;
        letter-spacing: 0.06em;
    }

    .site-header .nav-toggle {
        display: inline-flex;
        align-items: center;
        justify-content: center;
    }

    .site-header #site-nav {
        width: 100%;
        display: none;
        flex-direction: column;
        gap: 0.25rem;
        padding-top: 0.5rem;
        border-top: 1px solid var(--border);
    }

    .site-header.menu-open #site-nav {
        display: flex;
    }

    .site-header #site-nav a {
        display: block;
        padding: 0.7rem 0;
        font-size: 1rem;
    }
}

@media (max-width: 480px) {
    .site-header .logo-image {
        width: 40px;
        height: 45px;
        margin-top: -28px;
        margin-bottom: -28px;
    }

    .site-header .logo-text {
        font-size: 1rem;
    }

    .site-header .nav-toggle {
        padding: 0.3rem 0.5rem;
        font-size: 1.1rem;
    }
}