symfony-with-user-account/assets/styles/_account.scss

#account_main{
  display: flex;
  #account_nav{
    width: 20rem;
    padding: 1rem;
    ul{
    list-style-type: none;
      margin-right: 1rem;
      li{
        margin-bottom: 0.25rem;
        a{
          display: block;
        }
      }
    }
  }
  #account_main_content{
    width: 30rem;
  }
}