show_icon: true stops working when any styles: , extra_styles or card_mod is added

[WitteKraai]

Checklist

• [ X] I updated the card to the latest version available
• [X ] I cleared the cache of my browser

Describe the bug
When using show_icon: true alone, the icon renders correctly. However, as soon as any styling is added (via styles:, extra_styles, or card_mod), the icon disappears completely regardless of what styles are defined. Even a single harmless style like height: 50px on the card breaks the icon.

Version of the card
Version: v7.0.1

Home Assistant version:
core-2026.5.3

To Reproduce
This is the configuration I used:

Works (icon visible):

type: custom:button-card
entity: light.my_light
icon: mdi:chandelier
show_icon: true

Broken (icon invisible):

type: custom:button-card
entity: light.my_light
icon: mdi:chandelier
show_icon: true
styles:
  card:
    - height: 50px

Screenshots
N/A

Expected behavior
An icon that is showed and the possibilities to make styling for the button and/or icon with styles: extra_styles and/or card-mod.

Desktop (please complete the following information):

• Browser: Microsoft Edge (also reproduced on Android)
• card-mod version: v4.2.1
• Frosted Glass theme installed (but issue reproduces with default theme too)
  -Tested on clean dashboard with no other cards

Smartphone (please complete the following information):

• Device: Android (Samsung)
• OS: [e.g. iOS8.1]
• Browser [e.g. stock browser, safari]
• Version [e.g. 22]

Additional context
Beeing working on builing a nice setup for my lamps with help from Claude, but even Claude was unable to make some styling and a visible icon.