<style type='text/css'>
/* Setting size for the tiles */
div.ms-tileview-tile-root {
width: 160px !important;
height: 10px !important;
}
</style>
/*hiding the arrow buttons */Insert the code in script editor to hide the arrow buttons of tiles
<style>.ms-promlink-header{display:none;}</styleUsing script editor we can use below code to display tiles in 3 Rows and Columns
<style> width: 480px;}</style>
/*The Below CSS shows the Tiles in 2 Rows<style> width: 420px;}</style>