fix broken and deprecated CSS

speak property is deprecated 

broken display properties which was useless

css/style.css

@@ -122,7 +122,6 @@ sup {
     font-family: "stack-icons";
     font-style: normal;
     font-weight: normal;
-    speak: never;
     display: inline-block;
     text-decoration: inherit;
     text-align: center;
@@ -1147,7 +1146,6 @@ header .container {
 
 #download .container:before {
     content: 'download';
-    display; block;
     color: gainsboro;
     font-family: 'Noto Sans', sans-serif;
     font-weight: 700;
@@ -1299,7 +1297,6 @@ header .container {
 
 #features .container:before {
     content: 'features';
-    display; block;
     color: gainsboro;
     font-family: 'Noto Sans', sans-serif;
     font-weight: 700;
@@ -1499,7 +1496,6 @@ header .container {
 
 #support .container:before {
     content: 'support';
-    display; block;
     color: gainsboro;
     font-family: 'Noto Sans', sans-serif;
     font-weight: 700;