Replace hardcoded colors (gray-500, #b44, red-300/red-50/red-600,
green-600) with CSS variables for theme consistency. Add --destructive,
--error-*, --success-*, and --card-shadow variables to :root. Soften
default card borders from --border to --border-subtle and add 8-bit
style hard-offset shadows with hover effects. Apply accent-color for
themed checkboxes.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Remove ThemeToggle component, theme store, dark: Tailwind variants,
and dark color values from NOTE_COLORS. Simplify color logic to use
a single bg property. Delete dark mode e2e tests.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
