.main-sidebar {
    background: linear-gradient(180deg, #1a237e 0%, #283593 40%, #1565c0 100%) !important;
}
.main-sidebar .brand-link {
    background: rgba(0, 0, 0, 0.15) !important;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1) !important;
}
.main-sidebar .nav-sidebar .nav-link {
    color: rgba(255, 255, 255, 0.8) !important;
}
.main-sidebar .nav-sidebar .nav-link:hover {
    background: rgba(255, 255, 255, 0.1) !important;
    color: #fff !important;
}
.main-sidebar .nav-sidebar .nav-link.active {
    background: rgba(255, 255, 255, 0.2) !important;
    color: #fff !important;
}
.main-sidebar .nav-header {
    color: rgba(255, 255, 255, 0.5) !important;
}
.main-sidebar .nav-treeview {
    background: rgba(0, 0, 0, 0.1) !important;
}
.main-sidebar .nav-treeview .nav-link {
    color: rgba(255, 255, 255, 0.7) !important;
}
.main-sidebar .nav-treeview .nav-link:hover {
    color: #fff !important;
}
.main-sidebar .user-panel {
    border-bottom: 1px solid rgba(255, 255, 255, 0.1) !important;
}