images Coding block to use like a spacer to stop an image filling the whole mobile screen

Hi, can anyone urgently help me.

I have used pretty symbols (professionally designed , png ) to bring to life a very text heavy website. But I need them to sit centred above the text in the page. I have used spacers to centre and keep them small on desktop, but have just found that on mobile they stretch across the whole screen and are massive and blurry.

I am told I need a code block to add in instead of spacers.

I dont do coding so need help! Can anyone give me code for a block to use in this way?

Thank you - supposed to launch this weekend!!

Can you share link to this page? We can help easier