.site-header{
    position:sticky;
    top:0;
    z-index:999;
    background:rgba(255,255,255,.88);
    backdrop-filter:blur(16px);
    border-bottom:1px solid rgba(226,232,240,.86);
    box-shadow:0 10px 30px rgba(15,23,42,.045);
}

.header-inner{
    width:min(var(--ia-container-max,1280px),calc(100% - 48px));
    max-width:100%;
    margin:0 auto;
    min-height:78px;
    display:flex;
    align-items:center;
    justify-content:space-between;
    gap:22px;
}

.site-logo{
    display:flex;
    align-items:center;
    gap:10px;
    color:#2563eb;
    font-size:22px;
    font-weight:900;
    text-decoration:none;
    white-space:nowrap;
}

.logo-icon{
    width:42px;
    height:42px;
    display:flex;
    align-items:center;
    justify-content:center;
    border-radius:14px;
    background:linear-gradient(135deg,#eff6ff,#dbeafe);
    box-shadow:inset 0 1px 0 rgba(255,255,255,.9);
}

.main-menu{
    display:flex;
    align-items:center;
    justify-content:center;
    gap:6px;
    padding:6px;
    border:1px solid rgba(226,232,240,.92);
    border-radius:999px;
    background:rgba(248,250,252,.76);
}

.main-menu a{
    color:#0f172a;
    text-decoration:none;
    font-weight:800;
    font-size:14px;
    line-height:1;
    padding:11px 13px;
    border-radius:999px;
}

.main-menu a:hover,
.main-menu a:focus{
    color:#1d4ed8;
    background:#eff6ff;
}

.header-actions{
    display:flex;
    align-items:center;
    gap:12px;
}

.circle-btn{
    width:44px;
    height:44px;
    display:flex;
    align-items:center;
    justify-content:center;
    border-radius:50%;
    border:1px solid #e5e7eb;
    background:#fff;
    color:#0f172a;
    text-decoration:none;
    box-shadow:0 8px 20px rgba(15,23,42,.06);
}

.login-btn{
    height:46px;
    padding:0 24px;
    display:inline-flex;
    align-items:center;
    border-radius:15px;
    background:#2563eb;
    color:#fff;
    text-decoration:none;
    font-weight:900;
    box-shadow:0 12px 25px rgba(37,99,235,.24);
}

.login-btn:hover{
    color:#fff;
    background:#1d4ed8;
}

.mobile-menu-toggle{
    display:none;
    width:44px;
    height:44px;
    align-items:center;
    justify-content:center;
    flex-direction:column;
    gap:5px;
    padding:0;
    border:1px solid #e2e8f0;
    border-radius:14px;
    background:#fff;
    color:#0f172a;
    cursor:pointer;
    box-shadow:0 8px 20px rgba(15,23,42,.06);
}

.mobile-menu-toggle span[aria-hidden="true"]{
    width:20px;
    height:2px;
    border-radius:99px;
    background:currentColor;
    transition:transform .2s ease, opacity .2s ease;
}

.mobile-menu-toggle[aria-expanded="true"] span[aria-hidden="true"]:nth-of-type(2){
    transform:translateY(7px) rotate(45deg);
}

.mobile-menu-toggle[aria-expanded="true"] span[aria-hidden="true"]:nth-of-type(3){
    opacity:0;
}

.mobile-menu-toggle[aria-expanded="true"] span[aria-hidden="true"]:nth-of-type(4){
    transform:translateY(-7px) rotate(-45deg);
}

@media (max-width: 1024px){
    .main-menu{
        position:absolute;
        top:calc(100% + 10px);
        left:20px;
        right:20px;
        display:grid;
        grid-template-columns:repeat(2,minmax(0,1fr));
        gap:8px;
        padding:14px;
        border-radius:22px;
        background:rgba(255,255,255,.98);
        box-shadow:0 24px 55px rgba(15,23,42,.16);
        opacity:0;
        pointer-events:none;
        transform:translateY(-8px);
        transition:opacity .2s ease, transform .2s ease;
    }

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

    .main-menu a{
        padding:14px;
        background:#f8fafc;
    }

    .mobile-menu-toggle{
        display:flex;
    }
}

@media (max-width: 640px){
    .header-inner{
        width:min(calc(100% - 28px),var(--ia-container-max,1280px));
        min-height:70px;
        gap:10px;
    }

    .logo-icon{
        width:38px;
        height:38px;
    }

    .site-logo{
        font-size:19px;
    }

    .circle-btn,
    .login-btn{
        display:none;
    }

    .main-menu{
        grid-template-columns:1fr;
        left:14px;
        right:14px;
    }
}