Hi,
1. Please go to Appearance > Widgets > Footer#1 delete widget title
2. I help you corrected the code of form
<div class="signup-newsletter-form dib tc mb__15">
<input type="email" class="input-text" name="EMAIL" placeholder="Tu correo electrónico" required /><input type="submit" class="submit-btn" value="Unirme" />
</div>
<p class="tc">
Únete a la lista y obtén un 10% en tu primera compra. Recibe noticias, ofertas y novedades.
</p>
3,4. Please add below code to Claue > Theme Option > General Layout > Custom CSS
.mc4wp-form-basic .mc4wp-alert.mc4wp-success,
.mc4wp-form-theme .mc4wp-alert.mc4wp-success {
color: #468847;
}
.signup-newsletter-form input.submit-btn {
background: #222;
}
And change #222, #468847 to your color.
Kind regards
Harry
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