/* ──────────────────────────────────────────
   SIDEBAR    (variable-driven)
   ──────────────────────────────────────────*/
.sidebar {
    width: 220px;
    background: var(--background-dark);
    color: var(--text-light);
    display: flex;
    flex-direction: column;
    flex-shrink: 0;
    box-shadow: 3px 0 8px rgba(var(--black-rgb), .15);
    transition: width .3s ease;
}

/* Header ───────────────────────────────────*/
.sidebar-header {
    padding: 1.2rem 1rem;
    border-bottom: 1px solid var(--sidebar-divider);
    text-align: left;
}

.sidebar-brand {
    color: var(--text-light);
    font-size: 1.4rem;
    font-weight: 700;
    text-decoration: none;
    letter-spacing: .5px;
    display: block;
}

/* Nav block ────────────────────────────────*/
.sidebar-nav {
    padding: 1rem 0;
    flex-grow: 1;
}

    .sidebar-nav ul {
        list-style: none;
        margin: 0;
        padding: 0;
    }

    .sidebar-nav li {
        margin-bottom: 0;
    }

/* Top-level link ------------------------------------------------*/
.nav-link {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: .9rem 1.5rem;
    font-size: 1rem;
    color: var(--text-light);
    text-decoration: none;
    border-left: 4px solid transparent;
    transition: background-color .2s, color .2s, border-left-color .2s;
}

    .nav-link:hover {
        background: var(--sidebar-hover-bg); /* darker hover */
        color: var(--text-light);
    }

    .nav-link:focus-visible {
        outline: none;
        box-shadow: 0 0 0 .25rem var(--focus-ring);
    }

    .nav-link.active {
        background: var(--primary-color);
        border-left-color: var(--primary-dark);
        color: var(--text-light);
        font-weight: 600;
    }

/* Collapsible parents ------------------------------------------*/
.sidebar-nav .nav-parent > .nav-link {
    cursor: pointer;
}

.sidebar-nav .nav-parent-link .nav-arrow {
    margin-left: auto;
    transition: transform .3s;
}

.sidebar-nav .nav-parent-link.active .nav-arrow {
    transform: rotate(180deg);
    color: var(--text-light);
}

/* Sub-menu wrapper ---------------------------------------------*/
.sidebar-nav .nav-sub-menu {
    list-style: none;
    padding-left: 15px;
    margin: 0;
    display: none;
    overflow: hidden;
    background: var(--sidebar-sub-bg);
}

.sidebar-nav .nav-parent-link.active + .nav-sub-menu {
    display: block;
}

/* Sub-items -----------------------------------------------------*/
.sidebar-nav .nav-sub-item {
    padding: .5rem 1rem;
    font-size: .9rem;
    color: var(--text-light);
    transition: background-color .2s, color .2s;
}

    .sidebar-nav .nav-sub-item:hover {
        background: var(--sidebar-sub-hover-bg);
    }

    .sidebar-nav .nav-sub-item.active {
        background: var(--sidebar-sub-active-bg);
    }

/* Parent row while open ----------------------------------------*/
.sidebar-nav .nav-parent.active > .nav-link {
    background: var(--sidebar-sub-hover-bg);
    border-left-color: var(--sidebar-accent);
    color: var(--text-light);
    font-weight: bold;
}