The final artwork will be as like as below.
First create a gray background with
the rectangle tool. Then take the rounded rectangle tool and create a small rectangle. Fill it with white to white gradient. Then lower the opacity of the left color bucket.
Take two new bucket at the middle of the gradient bar. Lower the opacity of the left bucket. Your artwork will be look like below.
( Note : Drag the left bucket just above the right bucket of it. Then you will get a fresh rectangle. )
Now you have to add a stroke with full white color. Write something over the button. Make a copy of it by pressing CTRL + C and CTRL +B. Move the copy something under it and fill it with light gray color.
First create a gray background with
the rectangle tool. Then take the rounded rectangle tool and create a small rectangle. Fill it with white to white gradient. Then lower the opacity of the left color bucket.
Take two new bucket at the middle of the gradient bar. Lower the opacity of the left bucket. Your artwork will be look like below.
( Note : Drag the left bucket just above the right bucket of it. Then you will get a fresh rectangle. )
Now you have to add a stroke with full white color. Write something over the button. Make a copy of it by pressing CTRL + C and CTRL +B. Move the copy something under it and fill it with light gray color.
Finalizing work.
Now, change the background color and you will find a nice artwork like this.
