@Spay, You can try:
Step 1: Go to Shopify Admin -> Online Store ->Theme -> Edit code
Step 2: Search file theme.liquid
Step 3: Insert this code above </head> tag:
<style>
.prvw_block .block__cb input:checked + label {
border: 2px solid #15f0ed !important;
background-color: #eaffff !important;
}
.prvw_block .block__cb input + label {
border: 2px solid #cff3f3;
border-radius: 15px;
}
</style>
Hope this can help you,
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