fix: Fix empty Colors section in Theme Switcher (#4)

[sonikadeshwal]

Summary

Fixes #4 — The Colors section in the theme switcher was visible but displayed no color options.

Root Cause

The color swatch elements, their styles, and the JavaScript logic to apply accent colors were missing.

Changes Made

• index.html — Added 6 color dot swatches (Purple, Cyan, Red, Green, Orange, Pink) inside the Colors section
• css/style.css — Added styles for .color-dot, .color-options, and .active state
• js/script.js — Added setAccentColor() function that updates the CSS variable --accent-color and persists selection to localStorage

Behavior After Fix

• Color swatches are visible and clickable
• Selected color is highlighted with an active ring
• Chosen color persists on page refresh via localStorage
• Works correctly in both dark and light modes

Screenshots

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