CSS를 사용하여 어떻게 Django 양식의 스타일을 효과적으로 지정할 수 있나요?

class ContactForm(forms.Form):
    subject = forms.CharField(max_length=100)
    email = forms.EmailField(required=False)
    message = forms.CharField(widget=forms.Textarea)

<form action="" method="post">
  <table>
    {{ form.as_table }}
  </table>
  <input type="submit" value="Submit">
</form>

# forms.py
class ContactForm(forms.Form):
    subject = forms.CharField(widget=forms.TextInput(attrs={'class': 'subject'}))
    email = forms.EmailField(widget=forms.TextInput(attrs={'class': 'email'}))
    message = forms.CharField(widget=forms.Textarea(attrs={'class': 'message'}))

# forms.py
class ContactForm(forms.ModelForm):
    class Meta:
        model = MyModel

    def __init__(self, *args, **kwargs):
        super(ContactForm, self).__init__(*args, **kwargs)
        self.fields['subject'].widget.attrs.update({'class': 'subject'})
        self.fields['email'].widget.attrs.update({'class': 'email'})
        self.fields['message'].widget.attrs.update({'class': 'message'})

# forms.py
class ContactForm(forms.ModelForm):
    class Meta:
        model = MyModel
        widgets = {
            'subject': forms.TextInput(attrs={'class': 'subject'}),
            'email': forms.TextInput(attrs={'class': 'email'}),
            'message': forms.Textarea(attrs={'class': 'message'}),
        }