:root{--bg: #0a0a0f;--surface: #12121a;--surface2: #1a1a25;--blue: #3b82f6;--blue-light: #60a5fa;--blue-dim: #1e3a5f;--purple: #8b5cf6;--green: #22c55e;--red: #ef4444;--gold: #fbbf24;--text: #e2e8f0;--text-dim: #64748b;--font: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;--font-mono: "Courier New", monospace;--logo-size: 2.8rem;--tagline-size: 1.05rem;--cn-font-size: 3.6rem;--cn-font-weight: 600;--cn-line-height: 1.3;--en-cell-width: 45px;--en-cell-height: 80px;--en-font-size: 5rem;--en-font-weight: 500;--letter-gap: 0px;--word-gap: 10px;--space-width: 14px;--card-gap: 8.5rem;--practice-max-w: 90vw;--hint-font-size: 1.05rem;--flash-font-size: 3rem;--cn-font-size-mobile: 1.6rem;--en-cell-width-mobile: 34px;--en-cell-height-mobile: 44px;--en-font-size-mobile: 1.5rem;--space-width-mobile: 18px;--logo-size-mobile: 2rem;--flash-font-size-mobile: 2.4rem}