[design] remove menu opacity on edge box render

Author: zombieFox

src/css/menu.css

@@ -36,10 +36,6 @@
 transition: background-color var(--layout-timing-extra-fast), opacity var(--layout-timing-extra-fast);
 }
 
-.is-edge .menu-area{
-opacity:0.8;
-}
-
 .menu-nav{
 display: flex;
 flex-direction: row;