Product slider gallery & secondary menu

Hello

I am writing to you because I did not find the answer in WooCommerce documentation neither in Enfold. I have 2 issues : 1/ product gallery slider, 2/ Secondary menu issue

1/
I would like to make some changes in a product slider gallery. Let’s take this page as an example (the site is being built) : https://www.hoteo.fr/room-service/
There is a product-slider with 3 items (Burratta, Carots & Mushrooms) :
1/ How may I center the title of each item ?
2/ Is it possible to add a short description under the price of the item ?
3/ I would like to change the bottom button “ajouter au panier” by a “+”, how may I proceed ?
4/ If a person click on the image, is it possible to add the item directly in the cart ?
5/ If a person is on the product page after clicking on “plus de détails”, it is not possible/easy to find to come back to the previous page, is it possible to implement a button or is there any way to come back to the page ?

2/
On the home page of the website (you have to be on a desktop) : http://www.hoteo.fr/fr when you go over the main menu part “services” (you have also “A propos”, “FaQ”, “contact”), a secondary menu appears but it is ugly (take a look at the screen shot : https://www.hoteo.fr/wp-content/uploads/2018/01/Capture-d’écran-2018-01-18-à-11.56.38.png). How may I modify it : 1/ Change the size & the color of the font, 2/ reduce the space between the different items (here Taxi & Room-service) ? 3/ How may I reduce the size of the menu ?

Thx for your help

Best