iframe code not working well on mobiles

hi all

im looking for some help with iframe.

we’ve recently updates a iframe and now its not working very well on mobile devices, it just doesn’t justify and the search fields don’t shrink it size and images don’t fit the page.

is there any updates we an do or ccs code to add ?

TIA

<style>
.iframe-container iframe {border: 0; height: 100%; left: 0; position: absolute; top: 0; width: 100%;}
.iframe-container {overflow: hidden; padding-top: 425px; padding-bottom: 50px; position: relative;  }
</style>
<div class="iframe-container"><iframe src="https://files.evolved-tuning.co.uk/index.php?option=com_rsform&view=rsform&formId=74&bgcolor=999&fcolor=fff" width="100%" height="650px" scrolling="auto" allowfullscreen="allowfullscreen"></iframe></div>

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