.navbar-toggler-icon {
    background-image: url("data:image/svg+xml,<svg viewBox='0 0 30 30' xmlns='http://www.w3.org/2000/svg'><path stroke='rgba(0, 0, 0, 0.5)' stroke-width='2' stroke-linecap='round' stroke-miterlimit='10' d='M4 7h22M4 15h22M4 23h22'/></svg>");
}