.legacy-switch {
    position: fixed;
    top: 20px;
    left: 20px;
    z-index: 9999;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 9px 14px;
    color: var(--text-color);
    background: var(--section-bg);
    border: 1px solid var(--border-color);
    border-radius: 22px;
    box-shadow: 0 4px 12px rgba(102, 204, 255, 0.18);
    backdrop-filter: blur(8px);
    font-size: 0.82rem;
    font-weight: 700;
    text-decoration: none;
}

.legacy-switch:hover {
    color: #fff;
    background: var(--tianyi-blue);
}

@media (max-width: 768px) {
    .legacy-switch {
        top: 14px;
        left: 14px;
        padding: 7px 11px;
        font-size: 0.72rem;
    }
}