Resizing image on website for mobile?

Site URL: https://lion-pike-eywa.squarespace.com/

Hi, I'm trying to resize the banner image on my website for mobile so that the logo doesn't crop off in this display. I'm a beginner at CSS codes and have tried several codes i found online, of which none seem to work. Here's one I'm currently using:

@media only screen and (max-width:640px) { #block-55e89da83b15440928f7 {width:0%; margin:auto}}

Can someone help me figure out what I'm doing wrong?

https://lion-pike-eywa.squarespace.com/

Hi,

You mean Game Change Enablers image on mobile?

Add to Design > Custom CSS > Then save & reload the site

/* Resize background image effect */
@media screen and (max-width:767px) {
[data-section-id="6094ec2a8bdc1346da159ab6"] .section-background-content {
    z-index: 999;
    position: relative !important;
}
[data-section-id="6094ec2a8bdc1346da159ab6"] .section-background-canvas {
    visibility: hidden;
}
[data-section-id="6094ec2a8bdc1346da159ab6"] img {
    visibility: visible !important;
    height: auto !important;
}
[data-section-id="6094ec2a8bdc1346da159ab6"] {
    min-height: unset !important;
    height: 25vh !important;
}}

Worked like a charm @tuanphan Thanks so much!