:root {
    /* Light Mode Tokens */
    --color-bg: #f8fafc;
    --color-surface: #ffffff;
    --color-border: #e5e7eb;
    --color-text: #111827;
    --color-muted: #6b7280;

    /* Primary Palette */
    --primary-50: #fdf2f8;
    --primary-100: #fce7f3;
    --primary-200: #fbcfe8;
    --primary-300: #f9a8d4;
    --primary-400: #f472b6;
    --primary-500: #e11d8a;
    --primary-600: #be126e;
    --primary-700: #9d174d;
    --primary-800: #831843;
    --primary-900: #500724;

    /* Secondary Palette */
    --secondary-50: #eef2ff;
    --secondary-100: #e0e7ff;
    --secondary-200: #c7d2fe;
    --secondary-300: #a5b4fc;
    --secondary-400: #818cf8;
    --secondary-500: #6366f1;
    --secondary-600: #4f46e5;
    --secondary-700: #4338ca;
    --secondary-800: #3730a3;
    --secondary-900: #312e81;

    /* Semantic Accents */
    --color-success: #10b981;
    --color-warning: #f59e0b;
    --color-danger: #f43f5e;
    --color-info: #0ea5e9;

    /* Shadows */
    --shadow-sm: 0 1px 2px rgba(0,0,0,0.06);
    --shadow-md: 0 8px 24px rgba(0,0,0,0.08);
    --shadow-dark: 0 8px 24px rgba(0,0,0,0.35);

    /* Layout Dimensions */
    --top-bar-height: 64px;
    --nav-rail-width: 64px;
    --nav-rail-width-expanded: 240px;
}

[data-bs-theme="dark"] {
    --color-bg: #0f172a;
    --color-surface: #1e293b;
    --color-border: #334155;
    --color-text: #f1f5f9;
    --color-muted: #94a3b8;

    /* Soften primary in dark mode */
    --primary-500: #f472b6; /* Mapping to primary-400 visually */

    --shadow-md: var(--shadow-dark);
}

body {
    background-color: var(--color-bg);
    color: var(--color-text);
    font-family: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}

/* Component Overrides & Utilities */
.bg-surface { background-color: var(--color-surface) !important; }
.text-muted-custom { color: var(--color-muted) !important; }
.border-custom { border-color: var(--color-border) !important; }

/* Cards */
.card-custom {
    background-color: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: 1rem;
    box-shadow: var(--shadow-sm);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.card-custom:hover {
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

/* Buttons */
.btn-primary-custom {
    background-color: var(--primary-500);
    border-color: var(--primary-500);
    color: #ffffff;
}
.btn-primary-custom:hover {
    background-color: var(--primary-600);
    border-color: var(--primary-600);
    color: #ffffff;
}

/* Top Bar */
.top-bar {
    height: var(--top-bar-height);
    background-color: var(--color-surface);
    border-bottom: 1px solid var(--color-border);
    position: sticky;
    top: 0;
    z-index: 1020;
}

/* Nav Rail */
.nav-rail {
    width: var(--nav-rail-width);
    background-color: var(--color-surface);
    border-right: 1px solid var(--color-border);
    height: calc(100vh - var(--top-bar-height));
    position: fixed;
    top: var(--top-bar-height);
    left: 0;
    overflow-y: auto;
    transition: width 0.3s ease;
    z-index: 1010;
    display: flex;
    flex-direction: column;
}

.nav-rail.expanded {
    width: var(--nav-rail-width-expanded);
}

.nav-link-custom {
    color: var(--color-text);
    display: flex;
    align-items: center;
    padding: 0.75rem 1rem;
    text-decoration: none;
    white-space: nowrap;
    overflow: hidden;
    border-left: 4px solid transparent;
    transition: background-color 0.2s, border-color 0.2s;
}

.nav-link-custom:hover {
    background-color: var(--color-bg);
    color: var(--color-text);
}

.nav-link-custom.active {
    border-left-color: var(--primary-500);
    background-color: var(--primary-50);
    color: var(--primary-700);
}

[data-bs-theme="dark"] .nav-link-custom.active {
    background-color: rgba(225, 29, 138, 0.15); /* primary-500 with opacity */
    color: var(--primary-400);
}

.nav-icon {
    font-size: 1.25rem;
    min-width: 24px;
    margin-right: 1rem;
    text-align: center;
}

.nav-label {
    opacity: 0;
    transition: opacity 0.2s;
}

.nav-rail.expanded .nav-label {
    opacity: 1;
}

.nav-group-label {
    font-size: 0.75rem;
    text-transform: uppercase;
    color: var(--color-muted);
    padding: 1rem 1.25rem 0.5rem;
    display: none;
}

.nav-rail.expanded .nav-group-label {
    display: block;
}

/* Main Content */
.main-content {
    margin-left: var(--nav-rail-width);
    padding: 24px;
    transition: margin-left 0.3s ease;
    max-width: 1536px;
    margin-right: auto; /* Centering logic if width < screen */
}

.nav-rail.expanded ~ .main-content {
    margin-left: var(--nav-rail-width-expanded);
}

@media (min-width: 1200px) {
    .main-content {
        padding: 32px;
    }
}

/* Utilities */
.text-primary-custom { color: var(--primary-500) !important; }
.bg-primary-custom { background-color: var(--primary-500) !important; }

/* Search Input */
.search-input {
    background-color: var(--color-bg);
    border: 1px solid var(--color-border);
    color: var(--color-text);
}
.search-input:focus {
    background-color: var(--color-bg);
    color: var(--color-text);
    border-color: var(--primary-500);
    box-shadow: 0 0 0 0.25rem rgba(225, 29, 138, 0.25);
}

/* Avatar */
.avatar-circle {
    width: 32px;
    height: 32px;
    background-color: var(--secondary-200);
    color: var(--secondary-800);
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    font-weight: 600;
    font-size: 0.875rem;
}