UI: Improve maintenace actions design

[chakflying]

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Description

• Add margins and increase width to 100% in mobile view
• Remove inconsistent height of buttons in normal view
• Switch delete button to btn-normal

Type of change

• Bug fix (non-breaking change which fixes an issue)
• User interface (UI)

Checklist

• My code follows the style guidelines of this project
• I ran ESLint and other linters for modified files
• I have performed a self-review of my own code and tested it
• I have commented my code, particularly in hard-to-understand areas (including JSDoc for methods)
• My changes generates no new warnings
• My code needed automated testing. I have added them (this is optional task)

Screenshots (if any)

before	after