Add new header

[gsuarez90]

The application needs a new header. Make sure to keep the toggle theme, but just make sure the header looks nice and fits well with the rest of the application's UI.

[gsuarez90]

@claude can you fix this for me?

[claude]

Claude finished @gsuarez90's task in 2m 22s —— View job • claude/issue-2-20260518-2010 • Create PR ➔

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Add new header

• Gather context and read existing frontend code
• Understand current header structure and UI
• Implement new header (brand logo + title on left, theme toggle on right)
• Update CSS to style the header and integrate theme toggle
• Commit and push changes

What was done:

The previously hidden <header> has been replaced with a proper navbar-style site header. Changes across frontend/index.html and frontend/style.css:

• Logo — gradient book icon in a rounded tile on the left
• Title — "Course Materials Assistant" with the existing gradient text style, plus the subtitle underneath
• Theme toggle — moved from a floating fixed-position button (top-right corner) into the header's right side; fully functional with the same sun/moon icon transitions
• Responsive — subtitle hides on mobile (≤768px) to keep the header compact at 52px tall; desktop header is 60px
• Both light and dark themes are supported via CSS variables; the header transitions smoothly on theme switch

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