Move action button on the home page

I d like to move the action button on the home page to adapt the place of the button with my photographies in slider. For instance, how to move it from the left to the center ? If you could help me

Something like this in a custom CSS plugin should center the button:


.main-slider-caption > div {
        width: 100%;
}
.header-button {
        text-align: center;
}