css-sandbox/form/form.css

.form {
  display: flex;
  flex-direction: column;
  background-color: var(--color-form);
}

.form__submit {
  align-self: flex-end;
}

.form--horizontal {
  flex-direction: row;
  flex-wrap: wrap;
}

.form--horizontal .form__field {
  flex-grow: 1;
}

.form--inline .form__submit {
  flex: none;
  align-self: center;
}