Fix calendar layout overflow from KW column addition

[Copilot]

The KW (calendar week) column added an 8th column to the calendar grid, but the minimum width constraint remained at 250px (sized for 7 columns), causing cramped cells and overflow on smaller viewports.

Changes

• css/style.css: Increased .calendar grid minimum width from 250px to 300px to accommodate the additional 40px KW column

 .calendar {
   display: grid;
-  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
+  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
   gap: 10px;
   margin-bottom: 20px;
 }

Screenshots

Before (768px viewport):

After (768px viewport):

Layout now properly adapts across all viewport sizes (375px mobile through 1920px desktop) while maintaining responsive grid behavior.

Original prompt

The addition of the kw display breaks the layout, the days are now overflowing to the right side

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[github-actions]

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[github-actions]

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