:root {
    --sidebar-width: 260px;
    --topbar-height: 60px;
    --sidebar-bg: #1e2432;
    --sidebar-hover: #2a3244;
    --accent: #4361ee;
}

body {
    background-color: #f4f6f9;
    margin: 0;
}

.admin-sidebar {
    position: fixed;
    top: 0;
    left: 0;
    height: 100vh;
    width: var(--sidebar-width);
    background: var(--sidebar-bg);
    color: #fff;
    z-index: 1030;
    overflow-y: auto;
    transition: transform 0.3s ease;
}

.admin-sidebar .brand {
    height: var(--topbar-height);
    display: flex;
    align-items: center;
    padding: 0 1.25rem;
    font-weight: 600;
    font-size: 1.1rem;
    color: #fff;
    border-bottom: 1px solid rgba(255,255,255,0.08);
}

.admin-sidebar .nav-link {
    color: rgba(255,255,255,0.75);
    padding: 0.65rem 1.25rem;
    border-radius: 0;
    display: flex;
    align-items: center;
    gap: 0.6rem;
    cursor: pointer;
}

.admin-sidebar .nav-link:hover,
.admin-sidebar .nav-link.active {
    background: var(--sidebar-hover);
    color: #fff;
}

.admin-sidebar .submenu-link {
    padding-left: 2.75rem;
    font-size: 0.9rem;
    color: rgba(255,255,255,0.6);
}

.admin-sidebar .submenu-link:hover {
    color: #fff;
    background: var(--sidebar-hover);
}

.admin-sidebar [data-bs-toggle="collapse"] .bi-chevron-down {
    transition: transform 0.2s ease;
}

.admin-sidebar [data-bs-toggle="collapse"][aria-expanded="true"] .bi-chevron-down {
    transform: rotate(180deg);
}

.admin-topbar {
    position: fixed;
    top: 0;
    left: var(--sidebar-width);
    right: 0;
    height: var(--topbar-height);
    background: #fff;
    border-bottom: 1px solid #e5e7eb;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 1.25rem;
    z-index: 1020;
}

.admin-content {
    margin-left: var(--sidebar-width);
    padding-top: calc(var(--topbar-height) + 1.5rem);
    padding-left: 1.5rem;
    padding-right: 1.5rem;
    padding-bottom: 2rem;
    min-height: 100vh;
}

@media (max-width: 991.98px) {
    .admin-sidebar {
        transform: translateX(-100%);
    }
    .admin-sidebar.show {
        transform: translateX(0);
    }
    .admin-topbar,
    .admin-content {
        left: 0;
        margin-left: 0;
    }
}