allow overriding text-rendering

css/bulma.css

@@ -2329,7 +2329,7 @@ input[type="submit"].button {
   background: transparent;
 }
 
-.notification .delete {
+.notification > .delete {
   position: absolute;
   right: 0.5em;
   top: 0.5em;

sass/base/generic.sass

@@ -6,7 +6,7 @@ html
   min-width: 300px
   overflow-x: hidden
   overflow-y: scroll
-  text-rendering: optimizeLegibility
+  text-rendering: $render-mode
 
 article,
 aside,

sass/utilities/variables.sass

@@ -27,7 +27,8 @@ $red:          hsl(348, 100%, 61%) !default
 
 // Typography
 $family-sans-serif: -apple-system, BlinkMacSystemFont, "Segoe UI", "Roboto", "Oxygen", "Ubuntu", "Cantarell", "Fira Sans", "Droid Sans", "Helvetica Neue", "Helvetica", "Arial", sans-serif !default
-$family-monospace: monospace !default
+$family-monospace: monospace !default
+$render-mode: optimizeLegibility !default
 
 $size-1: 3rem !default
 $size-2: 2.5rem !default