Update web_src/css/base.css

Co-authored-by: silverwind <[email protected]>

Author: wxiaoguang

web_src/css/base.css

@@ -5,7 +5,7 @@
   /* GitHub explicitly sets font names like: "Apple Color Emoji", "Segoe UI Emoji", "Noto Color Emoji", "Twemoji Mozilla";
   Actually "Twemoji Mozilla" emoji font is widely used by browsers like Firefox, Pale Moon, and it is more likely up-to-dated than the system emoji font.
   So not setting emoji font seems to be the best choice, here we just use a non-existing dummy font name and let browsers choose. */
-  --fonts-emoji: "-emoji-fallback";
+  --fonts-emoji: -emoji-fallback;
   /* font weights - use between 400 and 600 for general purposes. Avoid 700 as it is perceived too bold */
   --font-weight-light: 300;
   --font-weight-normal: 400;