Thank you for reaching out and posting this question!
I understand you're looking to increase the font size for the product titles in the Collection list section on the Dawn theme. Since you're using a Shopify-supported theme, then this is something that our Theme Support team can help you with. If your store is subscribed to a plan, then you're eligible to use the complimentary design time included with your subscription for this customization. While we’re not able to provide account-specific support via the Shopify Community at this time, we’d be happy to continue assisting you through live chat, email, or callback. Please visit the Shopify Help Center and log in to your account to create a support request.
Have you considered using Shopify Inbox to communicate with customers on your shop?
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