:root {
  /* Colors */
  --color-bg: #f8f8f8;
  --color-surface: #ffffff;
  --color-surface-hover: #fafafa;
  --color-text: #111111;
  --color-text-secondary: #555555;
  --color-text-muted: #888888;
  --color-border: #d8d8d8;
  --color-border-light: #ebebeb;
  --color-border-focus: #111111;

  --color-accent: #111111;
  --color-accent-hover: #2a2a2a;
  --color-accent-subtle: rgba(17, 17, 17, 0.05);

  --color-positive: #16a34a;
  --color-positive-bg: #f0fdf4;
  --color-positive-border: #bbf7d0;
  --color-negative: #dc2626;
  --color-negative-bg: #fef2f2;
  --color-negative-border: #fecaca;
  --color-warning: #d97706;
  --color-warning-bg: #fffbeb;
  --color-warning-border: #fde68a;
  --color-info: #555555;
  --color-info-bg: #f5f5f5;
  --color-info-border: #d8d8d8;

  /* Column accent colors */
  --col-chat-accent: #3b82f6;
  --col-chat-accent-bg: rgba(59, 130, 246, 0.06);
  --col-builder-accent: #f59e0b;
  --col-builder-accent-bg: rgba(245, 158, 11, 0.06);
  --col-preview-accent: #16a34a;
  --col-preview-accent-bg: rgba(22, 163, 74, 0.06);

  /* Typography */
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", system-ui, sans-serif;
  --font-mono: "SF Mono", "Fira Code", "Cascadia Code", monospace;

  --text-xs: 0.75rem;
  --text-sm: 0.8125rem;
  --text-base: 0.9375rem;
  --text-lg: 1.125rem;
  --text-xl: 1.5rem;
  --text-2xl: 2rem;

  --weight-normal: 400;
  --weight-medium: 500;
  --weight-semibold: 600;
  --weight-bold: 700;

  /* Spacing */
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.25rem;
  --space-6: 1.5rem;
  --space-8: 2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;

  /* Borders & Radius */
  --border-thin: 1px solid var(--color-border);
  --border-radius-none: 0px;
  --border-radius-sm: 4px;
  --border-radius-md: 6px;
  --border-radius-lg: 20px;
  --border-radius-pill: 999px;

  /* Shadows */
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.08);
  --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.12);

  /* Focus */
  --focus-ring: 0 0 0 2px var(--color-surface), 0 0 0 4px var(--color-border-focus);

  /* Transitions */
  --transition-fast: 0.1s ease;
  --transition-base: 0.15s ease;
  --transition-slow: 0.25s ease;

  /* Layout */
  --sidebar-width: 220px;
  --sidebar-width-collapsed: 60px;
  --header-height: 52px;
  --pa-panel-width: 380px;
  --max-content-width: 1200px;
  --col-chat-width: 320px;
  --col-builder-width: 400px;
  --col-preview-width: 600px;

  /* Preview device widths */
  --preview-width-desktop: 1280px;
  --preview-width-tablet: 768px;
  --preview-width-mobile: 375px;

  /* Z-index */
  --z-sidebar: 10;
  --z-header: 20;
  --z-modal-backdrop: 100;
  --z-modal: 101;
  --z-toast: 200;
}