:root {
    /* --- Primitive Colors (Tailwind-like) --- */
    --color-white: #ffffff;
    --color-black: #000000;

    /* Slate (Neutrals) */
    --color-slate-50: #f8fafc;
    --color-slate-100: #f1f5f9;
    --color-slate-200: #e2e8f0;
    --color-slate-300: #cbd5e1;
    --color-slate-400: #94a3b8;
    --color-slate-500: #64748b;
    --color-slate-600: #475569;
    --color-slate-700: #334155;
    --color-slate-800: #1e293b;
    --color-slate-900: #0f172a;
    --color-slate-950: #020617;

    /* Indigo */
    --color-indigo-50: #eef2ff;
    --color-indigo-100: #e0e7ff;
    --color-indigo-200: #c7d2fe;
    --color-indigo-300: #a5b4fc;
    --color-indigo-400: #818cf8;
    --color-indigo-500: #6366f1;
    --color-indigo-600: #4f46e5;
    --color-indigo-700: #4338ca;
    --color-indigo-800: #3730a3;
    --color-indigo-900: #312e81;
    
    /* Brand */
    --color-brand-50: #eef4fc;
    --color-brand-100: #d9e7f8;
    --color-brand-200: #b7d0f1;
    --color-brand-300: #8eb3e6;
    --color-brand-400: #6697db;
    --color-brand-500: #4a81d0;
    --color-brand-600: #336cc2;
    --color-brand-700: #2d5da8;
    --color-brand-800: #274f8e;
    --color-brand-900: #203f6f;
    --color-brand: var(--color-brand-600);

    /* Red (Danger/Error) */
    --color-red-50: #fef2f2;
    --color-red-100: #fee2e2;
    --color-red-200: #fecaca;
    --color-red-300: #fca5a5;
    --color-red-400: #f87171;
    --color-red-500: #ef4444;
    --color-red-600: #dc2626;
    --color-red-700: #b91c1c;
    --color-red-800: #991b1b;
    --color-red-900: #7f1d1d;

    /* Emerald (Success) */
    --color-emerald-50: #ecfdf5;
    --color-emerald-100: #d1fae5;
    --color-emerald-200: #a7f3d0;
    --color-emerald-300: #6ee7b7;
    --color-emerald-400: #34d399;
    --color-emerald-500: #10b981;
    --color-emerald-600: #059669;
    --color-emerald-700: #047857;
    --color-emerald-800: #065f46;
    --color-emerald-900: #064e3b;

    /* Amber (Warning) */
    --color-amber-50: #fffbeb;
    --color-amber-100: #fef3c7;
    --color-amber-200: #fde68a;
    --color-amber-300: #fcd34d;
    --color-amber-400: #fbbf24;
    --color-amber-500: #f59e0b;
    --color-amber-600: #d97706;
    --color-amber-700: #b45309;
    --color-amber-800: #92400e;
    --color-amber-900: #78350f;

    /* Blue */
    --color-blue-50: #eff6ff;
    --color-blue-100: #dbeafe;
    --color-blue-200: #bfdbfe;
    --color-blue-300: #93c5fd;
    --color-blue-400: #60a5fa;
    --color-blue-500: #3b82f6;
    --color-blue-600: #2563eb;
    --color-blue-700: #1d4ed8;
    --color-blue-800: #1e40af;
    --color-blue-900: #1e3a8a;

    /* Gray */
    --color-gray-50: #f9fafb;
    --color-gray-100: #f3f4f6;
    --color-gray-200: #e5e7eb;
    --color-gray-300: #d1d5db;
    --color-gray-400: #9ca3af;
    --color-gray-500: #6b7280;
    --color-gray-600: #4b5563;
    --color-gray-700: #374151;
    --color-gray-800: #1f2937;
    --color-gray-900: #111827;

    /* Green */
    --color-green-50: #f0fdf4;
    --color-green-100: #dcfce7;
    --color-green-200: #bbf7d0;
    --color-green-300: #86efac;
    --color-green-400: #4ade80;
    --color-green-500: #22c55e;
    --color-green-600: #16a34a;
    --color-green-700: #15803d;
    --color-green-800: #166534;
    --color-green-900: #14532d;

    /* Yellow */
    --color-yellow-50: #fefce8;
    --color-yellow-100: #fef9c3;
    --color-yellow-200: #fef08a;
    --color-yellow-300: #fde047;
    --color-yellow-400: #facc15;
    --color-yellow-500: #eab308;
    --color-yellow-600: #ca8a04;
    --color-yellow-700: #a16207;
    --color-yellow-800: #854d0e;
    --color-yellow-900: #713f12;

    /* Purple */
    --color-purple-50: #faf5ff;
    --color-purple-100: #f3e8ff;
    --color-purple-200: #e9d5ff;
    --color-purple-300: #d8b4fe;
    --color-purple-400: #c084fc;
    --color-purple-500: #a855f7;
    --color-purple-600: #9333ea;
    --color-purple-700: #7e22ce;
    --color-purple-800: #6b21a8;
    --color-purple-900: #581c87;

    /* --- Semantic Theme Variables --- */

    /* Primary Brand Colors */
    --theme-primary-light: var(--color-brand-100);
    --theme-primary: var(--color-brand);
    --theme-primary-hover: var(--color-brand-700);
    --theme-primary-active: var(--color-brand-800);
    --theme-primary-text: var(--color-white);

    /* Backgrounds & Surfaces */
    --bg-body: var(--color-slate-50);
    --bg-surface: var(--color-white);
    --bg-surface-subtle: var(--color-slate-50);

    /* Text */
    --text-primary: var(--color-slate-900);
    --text-secondary: var(--color-slate-500);
    --text-tertiary: var(--color-slate-400);
    --text-on-primary: var(--color-white);

    /* Borders */
    --border-subtle: var(--color-slate-200);
    --border-default: var(--color-slate-300);
    --border-focus: var(--theme-primary);

    /* Statuses */
    --status-success: var(--color-emerald-600);
    --status-success-bg: var(--color-emerald-50);
    --status-warning: var(--color-amber-600);
    --status-warning-bg: var(--color-amber-50);
    --status-danger: var(--color-red-600);
    --status-danger-hover: var(--color-red-700);
    --status-danger-bg: var(--color-red-50);

    /* Spacing */
    --space-1: 0.25rem;
    --space-2: 0.5rem;
    --space-3: 0.75rem;
    --space-4: 1rem;
    --space-6: 1.5rem;
    --space-8: 2rem;

    /* Radius */
    --radius-sm: 0.25rem;
    --radius-md: 0.375rem;
    --radius-lg: 0.5rem;
    --radius-card: 0.75rem;
    --radius-full: 9999px;

    /* Shadows */
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);

    /* Typography */
    --font-sans: ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}

/* --- Component Classes (Utility-like) --- */

/* Buttons */
.sg-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
    padding: var(--space-2) var(--space-4);
    font-size: 0.875rem;
    font-weight: 500;
    line-height: 1.25rem;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all 0.2s ease-in-out;
    border: 1px solid transparent;
    text-decoration: none;
}

.sg-btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
}

.sg-btn-primary {
    background-color: var(--theme-primary);
    color: var(--theme-primary-text);
}

.sg-btn-primary:hover:not(:disabled) {
    background-color: var(--theme-primary-hover);
}

.sg-btn-secondary {
    background-color: var(--bg-surface);
    color: var(--text-primary);
    border-color: var(--border-default);
}

.sg-btn-secondary:hover:not(:disabled) {
    background-color: var(--color-slate-50);
    border-color: var(--color-slate-400);
}

.sg-btn-danger {
    background-color: var(--status-danger);
    color: var(--color-white);
}

.sg-btn-danger:hover:not(:disabled) {
    background-color: var(--status-danger-hover);
}

.sg-btn-ghost {
    background-color: transparent;
    color: var(--text-secondary);
}

.sg-btn-ghost:hover:not(:disabled) {
    background-color: var(--color-slate-100);
    color: var(--text-primary);
}

.sg-btn-sm {
    padding: var(--space-1) var(--space-3);
    font-size: 0.75rem;
}

.sg-btn-lg {
    padding: var(--space-3) var(--space-6);
    font-size: 1rem;
}

/* Inputs */
.sg-input {
    display: block;
    width: 100%;
    padding: var(--space-2) var(--space-3);
    font-size: 0.875rem;
    line-height: 1.5;
    color: var(--text-primary);
    background-color: var(--bg-surface);
    background-clip: padding-box;
    border: 1px solid var(--border-default);
    border-radius: var(--radius-md);
    transition: border-color 0.15s ease-in-out, box-shadow 0.15s ease-in-out;
}

.sg-input:focus {
    outline: none;
    border-color: var(--theme-primary);
    box-shadow: 0 0 0 3px var(--color-brand-100);
}

.sg-label {
    display: block;
    margin-bottom: var(--space-1);
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--text-secondary);
}

/* Cards */
.sg-card {
    background-color: var(--bg-surface);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-card);
    box-shadow: none;
}

.sg-card-header {
    padding: var(--space-4) var(--space-6);
    border-bottom: 1px solid var(--border-subtle);
    background-color: var(--bg-surface-subtle);
}

.sg-card-body {
    padding: var(--space-6);
}

.sg-card-footer {
    padding: var(--space-4) var(--space-6);
    border-top: 1px solid var(--border-subtle);
    background-color: var(--bg-surface-subtle);
}

/* Badges */
.sg-badge {
    display: inline-flex;
    align-items: center;
    padding: 0.125rem 0.5rem;
    border-radius: var(--radius-full);
    font-size: 0.75rem;
    font-weight: 600;
    line-height: 1;
}

.sg-badge-default {
    background-color: var(--color-slate-100);
    color: var(--color-slate-700);
}

.sg-badge-primary {
    background-color: var(--color-brand-50);
    color: var(--color-brand-700);
}

.sg-badge-success {
    background-color: var(--status-success-bg);
    color: var(--status-success);
}

.sg-badge-warning {
    background-color: var(--status-warning-bg);
    color: var(--status-warning);
}

.sg-badge-danger {
    background-color: var(--status-danger-bg);
    color: var(--status-danger);
}

/* Table */
.sg-table-container {
    width: 100%;
    overflow-x: auto;
    background-color: var(--bg-surface);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-card);
    box-shadow: none;
}

.sg-table {
    width: 100%;
    border-collapse: collapse;
    text-align: left;
    font-size: 0.875rem;
}

.sg-table th {
    background-color: var(--bg-surface-subtle);
    color: var(--text-secondary);
    font-weight: 600;
    padding: var(--space-3) var(--space-4);
    border-bottom: 1px solid var(--border-subtle);
}

.sg-table td {
    padding: var(--space-3) var(--space-4);
    border-bottom: 1px solid var(--border-subtle);
    color: var(--text-primary);
}

.sg-table tr:last-child td {
    border-bottom: none;
}

.sg-table tr:hover td {
    background-color: var(--color-slate-50);
}

/* Utilities */
.sg-text-muted {
    color: var(--text-secondary);
}

.sg-text-sm {
    font-size: 0.875rem;
}

.sg-font-medium {
    font-weight: 500;
}

.sg-font-semibold {
    font-weight: 600;
}

.sg-cursor-pointer {
    cursor: pointer;
}

.sg-text-center {
    text-align: center;
}

.sg-p-8 {
    padding: 2rem;
}

.sg-bg-slate-50 {
    background-color: var(--color-slate-50);
}

.sg-text-4xl {
    font-size: 2.25rem;
    line-height: 2.5rem;
}

.sg-text-slate-400 {
    color: var(--color-slate-400);
}

.sg-text-slate-500 {
    color: var(--color-slate-500);
}

.sg-mb-4 {
    margin-bottom: 1rem;
}

.sg-mb-2 {
    margin-bottom: 0.5rem;
}

.sg-ml-1 {
    margin-left: 0.25rem;
}

.sg-px-2 {
    padding-left: 0.5rem;
    padding-right: 0.5rem;
}

.sg-input-error {
    font-size: 0.75rem;
    color: var(--status-danger);
    margin-top: 0.25rem;
    font-weight: 500;
}

.sg-input-help {
    font-size: 0.75rem;
    color: var(--text-secondary);
    margin-top: 0.25rem;
}


.sg-text-danger {
    color: var(--status-danger);
}

.sg-text-danger-dark {
    color: var(--color-red-700);
}

.sg-border-danger-subtle {
    border-color: var(--color-red-200);
}

.sg-notice {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    gap: var(--space-4);
    padding: var(--space-3) var(--space-4);
    border: 1px solid var(--border-default);
    border-radius: var(--radius-md);
}

.sg-notice-main {
    display: flex;
    align-items: flex-start;
    gap: var(--space-3);
    min-width: 0;
}

.sg-notice-icon {
    margin-top: 0.125rem;
}

.sg-notice-title {
    margin: 0;
    font-size: 0.875rem;
    font-weight: 600;
}

.sg-notice-message {
    margin: 0;
    font-size: 0.875rem;
    line-height: 1.35;
}

.sg-notice-actions {
    display: flex;
    align-items: center;
    flex-shrink: 0;
}

.sg-notice-error {
    border-color: var(--color-red-200);
    background-color: var(--status-danger-bg);
    color: var(--color-red-700);
}

.sg-notice-warning {
    border-color: var(--color-amber-200);
    background-color: var(--status-warning-bg);
    color: var(--color-amber-700);
}

/* Animations */
@keyframes sg-spin {
    from {
        transform: rotate(0deg);
    }

    to {
        transform: rotate(360deg);
    }
}

.animate-spin {
    animation: sg-spin 1s linear infinite;
}

.sg-spinner {
    height: 1rem;
    width: 1rem;
}