fix(web): use system font stack per style guide

Fixes #66

Remove Inter and Roboto from font-family. The style guide specifies
system fonts only: -apple-system, BlinkMacSystemFont, Segoe UI,
system-ui, sans-serif.

web/src/styles/global.css

@@ -1,4 +1,4 @@
-@import './theme.css';
+@import "./theme.css";
 
 *,
 *::before,
@@ -9,7 +9,8 @@
 }
 
 body {
-  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
+    font-family:
+        -apple-system, BlinkMacSystemFont, "Segoe UI", system-ui, sans-serif;
     background-color: var(--ctp-base);
     color: var(--ctp-text);
     line-height: 1.6;
@@ -46,6 +47,8 @@ a:hover {
 }
 
 /* Monospace */
-code, pre, .mono {
-  font-family: 'JetBrains Mono', 'Fira Code', monospace;
+code,
+pre,
+.mono {
+    font-family: "JetBrains Mono", "Fira Code", monospace;
 }