[design] improve range style on firefox

Author: zombieFox

src/css/form.css

@@ -464,6 +464,14 @@ input[type="range"]::-moz-range-track{
 -webkit-appearance: none;
 }
 
+input[type="range"]:focus::-moz-range-track{
+background-color:rgb(var(--theme-style-text));
+}
+
+input[type="range"]::-moz-focus-outer{
+border:0;
+}
+
 input[type="range"]::-moz-range-thumb{
 background-color:rgb(var(--theme-gray-01));
 color:rgb(var(--form-range-thumb));