.side-menu {
    width: 240px;
    /*background: rgba(255, 255, 255, 0.99);*/
    list-style: none;
    z-index: var(--z-sticky);
    position: absolute;
    left: var(--space-sm);
    height: 100%;
    box-shadow: 10px 0 30px rgba(0, 0, 0, 0.05);
    border: 1px solid rgba(0, 0, 0, 0.05);
    margin-left: var(--space-md);
    display: none;
    padding: 0;
    top: 56px;
}

.all-category-btn.always:not(.collapsed) .side-menu {
    display: block;
}

.side-menu > li {
    padding: 14px 25px;
    border-bottom: 1px solid rgba(0, 0, 0, 0.02);
    background: var(--color-bg-card);
    cursor: pointer;
    transition: all 0.3s;
    display: flex;
    justify-content: space-between;
    align-items: center;

    position: relative;
    z-index: var(--z-dropdown);
    color: var(--color-text-secondary);
}

.side-menu > li a {
    text-decoration: none;
    font-size: var(--font-size-btn);
    color: var(--color-text-secondary);
}

.side-menu > li i:first-child {
    transition: all 0.3s;
    width: 25px;
    color: var(--color-text-secondary);
}

.side-menu > li:hover {
    background: var(--color-primary);
    padding-left: 35px;
    color: var(--color-bg-card);
}

.side-menu > li:hover i,
.side-menu > li:hover > a {
    color: var(--color-bg-card);
}

.side-menu .sub-menu {
    position: absolute;
    top: 0;
    left: 240px;
    width: 280px;
    background: var(--color-bg-card);
    box-shadow: var(--shadow-md);
    list-style: none;
    padding: 15px 0;
    display: none;
    z-index: var(--z-dropdown);
    border-radius: 0 4px 4px 0;
}

.side-menu > li:hover .sub-menu {
    display: block;
    animation: subMenuFade 0.3s ease forwards;
}

.sub-menu > li {
    padding: 10px 25px;
    transition: all 0.2s ease;
    font-size: var(--font-size-caption);
}

.sub-menu > li > a {
    text-decoration: none;
    color: var(--color-text-body);
    display: block;
    width: 100%;
    height: 100%;
}

.sub-menu > li:hover {
    background: #f8f8f8;
    padding-left: 30px;
}

.sub-menu > li:hover a {
    color: var(--color-primary);
}

@keyframes subMenuFade {
    0% {
        opacity: 0;
        transform: translateX(10px);
    }
    100% {
        opacity: var(--z-base);
        transform: translateX(0);
    }
}