我通过将parrent添加到.content-grid来解决这个问题。
指令码

/* Add parent to element */
jQuery(document).ready(function($) {
    $('.content-grid').wrap('<div class="grid-parent"></div>');
});

/* How to add a class to another class if the collapse menu is open */
jQuery(document).ready(function($) {
    $('.sidemenu-trigger').on('click', function(e) {
        if ($(".sidemenu-trigger").hasClass("active")) {
            $('.grid-parent').addClass('collapsed-menu-grid-parent')
              .css({
                  'whatever' : 'whatever',
              });
        } else {
            $('.grid-parent').removeClass('collapsed-menu-grid-parent')
              .css({
                  'whatever' : 'whatever',
              });
        }
    });
});

CSS

.grid-parent {
    display: block;
    left: 80px;
    width: -webkit-calc(100% - 80px);
    width: -moz-calc(100% - 80px);
    width: calc(100% - 80px);
    position: relative;
    transition: all 0.4s ease-in-out 0s;
}

.collapsed-menu-grid-parent {
    display: block;
    left: 300px;
    width: -webkit-calc(100% - 300px);
    width: -moz-calc(100% - 300px);
    width: calc(100% - 300px);
    position: relative;
    transition: all 0.4s ease-in-out 0s;
}