SharePoint 2013 change look single page. (CSS)

There a lot of time that I have to do some css modification to specific home page like remove spacing between the banner and the content. I script editor  to modified style and/or add additional javascript.

example:

1) Insert script editor webpart
2) insert following to override some css.
<style>
#suiteBar {DISPLAY: none}
.ms-core-navigation { DISPLAY: none }
#contentBox { margin-left: 0px }
.ms-mpSearchBox {DISPLAY: none}
.ms-siteactions-normal {DISPLAY: none}
</style>