.ach-nav-loading-overlay {
    position: fixed;
    inset: 0;
    z-index: 99999;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 24px;
    background: rgba(255, 255, 255, 0.88);
    backdrop-filter: blur(4px);
    -webkit-backdrop-filter: blur(4px);
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.15s ease, visibility 0.15s ease;
}

.ach-nav-loading-overlay.is-visible {
    opacity: 1;
    visibility: visible;
}

.ach-nav-loading-overlay__card {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 14px;
    min-width: min(280px, 90vw);
    padding: 24px 28px;
    background: #fff;
    border: 1px solid #e8eaed;
    border-radius: 16px;
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.12);
    text-align: center;
}

.ach-nav-loading-overlay__spinner {
    width: 42px;
    height: 42px;
    border: 3px solid #e8eaed;
    border-top-color: #0073bb;
    border-radius: 50%;
    animation: ach-nav-spin 0.75s linear infinite;
}

.ach-nav-loading-overlay__text {
    margin: 0;
    font-size: 15px;
    font-weight: 700;
    color: #111;
    line-height: 1.35;
}

.ach-nav-loading-overlay__sub {
    margin: 0;
    font-size: 12px;
    color: #666;
    line-height: 1.4;
}

body.ach-nav-loading-active {
    overflow: hidden;
    touch-action: none;
}

body.dark-mode .ach-nav-loading-overlay {
    background: rgba(18, 18, 18, 0.9);
}

body.dark-mode .ach-nav-loading-overlay__card {
    background: #1e1e1e;
    border-color: #333;
}

body.dark-mode .ach-nav-loading-overlay__text {
    color: #f0f0f0;
}

body.dark-mode .ach-nav-loading-overlay__sub {
    color: #aaa;
}

body.dark-mode .ach-nav-loading-overlay__spinner {
    border-color: #333;
    border-top-color: #4da3ff;
}

@keyframes ach-nav-spin {
    to {
        transform: rotate(360deg);
    }
}