[data-theme="dark"] {
    --color-gray-50: #111827;
    --color-gray-100: #1F2937;
    --color-gray-200: #374151;
    --color-gray-300: #4B5563;
    --color-gray-500: #9CA3AF;
    --color-gray-700: #D1D5DB;
    --color-gray-900: #F9FAFB;

    --bg-body: #121212;
    /* Deep Black for body */
    --bg-card: #1E1E1E;
    /* Dark Gray for components */
    --bg-header: #1E1E1E;

    --text-main: #f1f5f9;
    --text-muted: #94a3b8;

    /* Borders lighter to be visible on dark */
    --color-gray-200: #333333;
}

/* Ensure grid lines are visible but subtle in dark mode */
[data-theme="dark"] .grid-cell-hour {
    border-bottom-color: #2a2a2a !important;
}

[data-theme="dark"] .day-column {
    border-left-color: #2a2a2a !important;
}