How to use Shopify theme settings to create mobile-specific logos |

duplicate-logo-markup.liquid

{% if section.settings.logo != blank %}
  {% capture image_size %}{{ section.settings.logo_max_width }}x{% endcapture %}
    <img src="{{ section.settings.logo | img_url: image_size }}"
         srcset="{{ section.settings.logo | img_url: image_size }} 1x, {{ section.settings.logo | img_url: image_size, scale: 2 }} 2x"
         alt="{{ section.settings.logo.alt | default: shop.name }}">
{% else %}
  {{ shop.name }}
{% endif %}

{% if section.settings.mobile_logo != blank %}
  {% capture image_size %}{{ section.settings.mobile_logo_max_width }}x{% endcapture %}
    <img src="{{ section.settings.mobile_logo | img_url: image_size }}"
         srcset="{{ section.settings.mobile_logo | img_url: image_size }} 1x, {{ section.settings.mobile_logo | img_url: image_size, scale: 2 }} 2x"
         alt="{{ section.settings.logo.alt | default: shop.name }}">
{% else %}
  {{ shop.name }}
{% endif %}