Solution: This is usually a subpixel rendering or weight mapping issue. On macOS, go to System Settings > Displays and ensure "Use font smoothing when available" is enabled. Also, avoid using font-weight: 500 or 600 unless you have verified the font supports it (only W3 and W6 are standard).
Hiragino Sans CNS sits in a unique middle ground. It is not a heavy, serifed Ming typeface (like Times New Roman for Chinese), nor is it a hyper-geometric grotesk. Instead, it offers: hiragino sans cns
Hiragino Sans CNS is not included with Windows. You can: Solution: This is usually a subpixel rendering or