A small green line in the Shopify Impulse Header

Topic summary

A user wants to add a 2px green horizontal line (#83861B) below the menu items in the Shopify Impulse theme, spanning full width on both desktop and mobile. They’ve provided a screenshot showing the desired placement and specified that white space must remain between the line and content below.

Another participant questions the value of this customization, raising concerns about:

  • Whether it genuinely improves user experience
  • Potential loss of automatic theme updates from Shopify
  • Responsive design issues—the line could break the layout on smaller screens or when menu items increase/lengthen

The discussion remains open with no technical solution provided yet, and the UX/maintenance concerns unaddressed.

Summarized with AI on November 4. AI used: claude-sonnet-4-5-20250929.

Hi I would like to add a green, small line under the menu items of the shopify impulse theme like in the screenshot attached.

color: #83861B

2px

full width (desktop & mobile)

There must be white space under the line like on the screenshot image.

I am grateful for any help. Thanks in advance!

I have just one question - why? Will it really improve the UX? It could even take your Impulse theme out of the updates stream. And if your menu adds items or becomes longer or is on a smaller screen size then it will do a line break and look totally NAF!