Делаем подчеркивания пунктов главного меню в Xenforo 2.1

[baltun]

Добавляем фрагмент данного кода в шаблон extra.less:

.js-offCanvasNavSource .p-navEl .p-navEl-link:hover:after {
    width: 100%;
    transition: 1s all;
}
.js-offCanvasNavSource .p-navEl.is-selected .p-navEl-link:after {
    background: none;
}
.js-offCanvasNavSource .p-navEl .p-navEl-link:after {
    position: absolute;
    bottom: 5px;
    width: 0;
    height: 3px;
    background: #bcdef5;
    content: "";
    left: 0;
}
.js-offCanvasNavSource .p-navEl {
    position: relative;
}