Am I making a mistake?

[Jose Nilton Pace]

Hi David, i use templates all the time. I studied a little HTML / CSS / JS to improve my programs and today I'm not going back.
You can see these 2 simple programs that are open to the public.
https://jnp.com.br/fidelidade/$/start/?cnpj=57957482000190
and
https://entremeios.com.br/gerencial/$/start/?cnpj=67428110000120

I use AdminLTE in all my programs.
https://adminlte.io/