Need Help To Place Mobile Buttons Side-By-Side

Site URL: https://decade3.co.uk

So on the home page of our website I'd like to change the buttons at the bottom to be displayed side-by-side ("Learn More" and "Talk To Us"). Right now the furthest I've gone with the code to centralise the buttons on mobile is: 
 

@media screen and (max-width:640px) {
.sqs-block-button * {
    text-align: center !important;
}
}

But I'd very much like them to be displayed side-by-side on mobile, as in browser: 

 How do I achieve this? 

Add to Home > Design > Custom CSS

/* buttons side by side */
@media screen and (max-width:767px) {
div#page-section-5f7565448036587780a97721 .span-12>.row:nth-child(2) .span-6 {
    width: 50% !important;
    float: left !important;
}
}

Thanks @tuanphan! One last bit of help, the button text doesn't seem centered on mobile anymore- is there a way to fix this, maybe even custom resize the buttons?

Remove above & use new code

/* buttons side by side */
@media screen and (max-width:767px) {
div#page-section-5f7565448036587780a97721 .span-12>.row:nth-child(2) .span-6 {
    width: 50% !important;
    float: left !important;
}
div#page-section-5f7565448036587780a97721 .span-12>.row:nth-child(2) .span-6 a {
    padding: 10px 25px;
}
}