💄 Finished the common style settings.

assets/css/_common/outline/header/menu.scss

@@ -0,0 +1,56 @@
+// Menu
+// --------------------------------------------------
+.menu {
+  margin: 0;
+  padding: 1em 0;
+  text-align: center;
+}
+
+.menu-item {
+  display: inline-block;
+  list-style: none;
+  margin: 0 10px;
+
+  @include mobile() {
+    display: block;
+    margin-top: 10px;
+
+    &.menu-item-search {
+      display: none;
+    }
+  }
+
+  a {
+    border-bottom: 0;
+    display: block;
+    font-size: $font-size-smaller;
+    transition: border-color $transition-ease;
+
+    &:hover, &.menu-item-active {
+      background: var(--menu-item-bg-color);
+    }
+  }
+
+  .fa, .fab, .far, .fas {
+    margin-right: 8px;
+  }
+
+  .badge {
+    display: inline-block;
+    font-weight: bold;
+    line-height: 1;
+    margin-left: .35em;
+    margin-top: .35em;
+    text-align: center;
+    white-space: nowrap;
+
+    @include mobile() {
+      float: right;
+      margin-left: 0;
+    }
+  }
+}
+
+.use-motion .menu-item {
+  visibility: hidden;
+}