Buttons too small

Trying to insert button onto side bar, but buttons are not big enough. They are very small. May be simple mistake I am making as I am very new to WP

Here is link to page with buttons on right

http://lvtemple.org/?event=guru-poornima-satyanarayana-vratham&preview=true&preview_id=456&preview_nonce=46d442c59e

https://ww.wp.xz.cn/plugins/paypal-donations/