:root {
    /* Typography */
    --font-family-base: "Inter", "Segoe UI", system-ui, -apple-system, BlinkMacSystemFont, "Helvetica Neue", sans-serif;
    --font-size-base: 16px;
    --font-size-sm: 0.875rem;
    --font-size-xs: 0.8125rem;
    --font-size-lg: 1.125rem;
    --line-height-base: 1.5;
    --font-weight-regular: 400;
    --font-weight-medium: 500;
    --font-weight-semibold: 600;
    --font-weight-bold: 700;

    /* Neutral palette */
    --color-neutral-0: #ffffff;
    --color-neutral-25: #f8fafc;
    --color-neutral-50: #f1f5f9;
    --color-neutral-100: #e2e8f0;
    --color-neutral-200: #cbd5ff;
    --color-neutral-300: #cbd5e1;
    --color-neutral-400: #94a3b8;
    --color-neutral-500: #64748b;
    --color-neutral-600: #475569;
    --color-neutral-700: #334155;
    --color-neutral-800: #1e293b;
    --color-neutral-900: #0f172a;

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

    /* Semantic colors */
    --color-success: #10b981;
    --color-success-soft: #ecfdf5;
    --color-warning: #f59e0b;
    --color-warning-soft: #fffbeb;
    --color-danger: #ef4444;
    --color-danger-soft: #fef2f2;
    --color-info: #06b6d4;
    --color-info-soft: #ecfeff;

    /* Surfaces & text */
    --surface-app: var(--color-neutral-25);
    --surface-card: var(--color-neutral-0);
    --surface-muted: var(--color-neutral-50);
    --surface-strong: var(--color-neutral-100);
    --surface-inverse: var(--color-neutral-900);
    --text-primary: var(--color-neutral-900);
    --text-secondary: var(--color-neutral-600);
    --text-muted: var(--color-neutral-500);

    /* Borders & shadows */
    --border-color: var(--color-neutral-100);
    --border-strong: var(--color-neutral-200);
    --shadow-xs: 0 1px 2px rgba(15, 23, 42, 0.08);
    --shadow-sm: 0 2px 6px rgba(15, 23, 42, 0.10);
    --shadow-md: 0 8px 24px rgba(15, 23, 42, 0.12);
    --shadow-lg: 0 18px 40px rgba(15, 23, 42, 0.16);

    /* Radii */
    --radius-xs: 6px;
    --radius-sm: 10px;
    --radius-md: 14px;
    --radius-lg: 20px;
    --radius-pill: 999px;

    /* Spacing scale */
    --space-xxs: 0.25rem;
    --space-xs: 0.5rem;
    --space-sm: 0.75rem;
    --space-md: 1rem;
    --space-lg: 1.5rem;
    --space-xl: 2rem;
    --space-xxl: 3rem;

    /* Component dimensions */
    --sidebar-width: 272px;
    --sidebar-width-collapsed: 84px;
    --topbar-height: 72px;
    --container-max-width: 1480px;

    /* Iconography */
    --icon-size-base: 1.1rem;
    --icon-size-lg: 1.35rem;
    --icon-size-xl: 1.75rem;

    /* Motion */
    --transition-fast: 120ms ease;
    --transition-base: 220ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 420ms cubic-bezier(0.4, 0, 0.2, 1);

    /* Gradients */
    --gradient-brand: linear-gradient(135deg, #3b82f6 0%, #2563eb 100%);
    --gradient-success: linear-gradient(135deg, #10b981 0%, #0d9488 100%);
    --gradient-warning: linear-gradient(135deg, #f59e0b 0%, #f97316 100%);
    --gradient-danger: linear-gradient(135deg, #ef4444 0%, #dc2626 100%);
    --gradient-magenta: linear-gradient(135deg, #a855f7 0%, #ec4899 100%);
}

[data-theme='dark'] {
    --surface-app: var(--color-neutral-900);
    --surface-card: #131c2f;
    --surface-muted: #0f1725;
    --surface-strong: #1f2a3d;
    --surface-inverse: #0b1120;
    --border-color: rgba(148, 163, 184, 0.2);
    --border-strong: rgba(148, 163, 184, 0.3);
    --text-primary: #f1f5f9;
    --text-secondary: #cbd5f5;
    --text-muted: #94a3b8;
    --shadow-xs: 0 1px 2px rgba(0, 0, 0, 0.6);
    --shadow-sm: 0 4px 12px rgba(15, 23, 42, 0.45);
    --shadow-md: 0 12px 30px rgba(0, 0, 0, 0.55);
    --shadow-lg: 0 18px 40px rgba(0, 0, 0, 0.65);
}