Uses the native font of the operating system to get close to a native app feel.
- The browser looks for each successive font, preferring the first one if possible, and falls back to the next if it cannot find the font (on the system or defined in CSS).
 -apple-systemis San Francisco, used on iOS and macOS (not Chrome however).BlinkMacSystemFontis San Francisco, used on macOS Chrome.Segoe UIis used on Windows 10.Robotois used on Android.Oxygen-Sansis used on Linux with KDE.Ubuntuis used on Ubuntu (all variants).Cantarellis used on Linux with GNOME Shell."Helvetica Neue"andHelveticais used on macOS 10.10 and below (wrapped in quotes because it has a space).Arialis a font widely supported by all operating systems.sans-serifis the fallback sans-serif font if none of the other fonts are supported.
预览
This text uses the system font.
HTML
<p class="system-font-stack">This text uses the system font.</p>
CSS
.system-font-stack {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen-Sans, Ubuntu,
    Cantarell, 'Helvetica Neue', Helvetica, Arial, sans-serif;
}