newslettersignupwithsuccessmessage

Hey there buddy, here's what you can do.........

• first of all be clear in mind that you will work only with the main-grid component, there's no need of a second-grid, use the below code to center your main-grid

.main-grid{
        width: [value]%
        margin: [value]rem/em auto;

that will do the work to center the component....

• secondly use the same-classes and that you used to position your main-grid component, like the text-classes as it would help you to reduce the redundancy.....

• now create a hide class to hide the signup-form on button-click, the hide class should be like the below code....

.hide{
    display: none;
}

• use the event-listener to toggle between the hide class to show up the thank you message...

This would be the start to adding modifications to your project, I would suggest you to learn the DOM Manipulation, watch these tutorials and try to resolve your issue

I hope that would be great to start in the right direction for modifications....... glad if I can be of any use to you....... do let me know what happened after you alter your code!!