:root {
  color-scheme: dark;

  --tc-bg: #171b24;
  --tc-bg-alt: #151922;
  --tc-nav: #11151c;

  --tc-surface: #1d222d;
  --tc-surface-raised: #222936;
  --tc-surface-subtle: rgba(255, 255, 255, 0.025);
  --tc-surface-hover: rgba(255, 255, 255, 0.045);

  --tc-text: #f5f7fa;
  --tc-text-secondary: #c8ced8;
  --tc-text-muted: #8e98a8;

  --tc-line: rgba(255, 255, 255, 0.08);
  --tc-line-strong: rgba(255, 255, 255, 0.13);

  --tc-accent: #58d5d9;
  --tc-accent-hover: #76e3e6;
  --tc-accent-subtle: rgba(88, 213, 217, 0.10);
  --tc-accent-contrast: #082628;

  --tc-success: #70d6a1;
  --tc-success-subtle: rgba(112, 214, 161, 0.10);
  --tc-warning: #e8bd68;
  --tc-warning-subtle: rgba(232, 189, 104, 0.10);
  --tc-danger: #e9828c;
  --tc-danger-subtle: rgba(233, 130, 140, 0.10);

  --tc-font-sans: Inter, Geist, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --tc-font-mono: "SFMono-Regular", Consolas, "Liberation Mono", monospace;

  --tc-space-1: 4px;
  --tc-space-2: 8px;
  --tc-space-3: 12px;
  --tc-space-4: 16px;
  --tc-space-5: 20px;
  --tc-space-6: 24px;
  --tc-space-8: 32px;
  --tc-space-10: 40px;
  --tc-space-12: 48px;
  --tc-space-16: 64px;

  --tc-radius-sm: 8px;
  --tc-radius-md: 10px;
  --tc-radius-lg: 14px;
  --tc-radius-xl: 16px;

  --tc-shadow-raised: 0 8px 24px rgba(0, 0, 0, 0.18);

  --tc-header-height: 68px;
  --tc-control-height: 44px;
  --tc-content-max: 1320px;
  --tc-reader-max: 76ch;

  --tc-transition-fast: 140ms ease;
}