Change color of sub-sub menu text & banner in mobile view

Hi,
#Problem 1
i am using theme isle on my site and i want to change the color of sub sub menu text because when user click on menu drop down button, its quite difficult to see difference between sub menu item and sub sub menu items. kindly look refer this image https://ibb.co/NyRW2KT
https://ibb.co/c2kwvF7

When user click on drop down button, color of sub sub menu items should be different from the sub menu items.

#Problem 2
When site is opened in mobile. It shows 1 banner in line and 6 afterwords one by one and i want to get two banners in one line. Refer this image https://ibb.co/GFCx90j
I tried this code in customize additional css editor

@media only screen and (max-width: 420px) {
.shop_isle_bannerss_section .col-sm-4 {
width: 50%;

But it doesn’t work properly, as you can see the image https://ibb.co/28Zc2kv

That code works perfect in tablet and desktop mode but not in mobile mode.

I hope you guys understood my issue, kindly know me if you need more details.

Thank you so much

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