.main-sidebar .nav-sidebar .module-collapsible-header {
    cursor: pointer;
    user-select: none;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.main-sidebar .nav-sidebar .module-collapsible-header::after {
    content: '';
    width: 0;
    height: 0;
    border-top: 5px solid transparent;
    border-bottom: 5px solid transparent;
    border-left: 6px solid rgba(255, 255, 255, 0.78);
    transform: rotate(90deg);
    transform-origin: 35% 50%;
    transition: transform 0.2s ease, opacity 0.2s ease;
    opacity: 0.85;
}

.main-sidebar .nav-sidebar .module-collapsible-header.is-collapsed::after {
    transform: rotate(0deg);
    opacity: 0.72;
}

.main-sidebar .nav-sidebar .module-collapsible-header:hover::after,
.main-sidebar .nav-sidebar .module-collapsible-header:focus-visible::after {
    opacity: 1;
}

.main-sidebar .nav-sidebar .module-collapsible-header:focus-visible {
    outline: 2px solid rgba(255, 255, 255, 0.45);
    outline-offset: 2px;
    border-radius: 4px;
}

@media (prefers-reduced-motion: reduce) {
    .main-sidebar .nav-sidebar .module-collapsible-header::after {
        transition: none;
    }
}